TÍNH

TOÁN

THI

T

K

K

T

C

U

KHUNG

NGANG

N

i

dung:

Thi

ế

t

k

ế

khung

ngang

tr

c

8

c

a

m

t

tr

s

c

ơ

quan

v

i

m

t

b

ng

m

t

c

t

nh

ư

hình

v

.

Đị

a

đ

i

m

xây

d

ng

TP.Tuy

Hòa,

Phú

Yên.

A

E

D

0.000

±

C

B

A

A

3600

3600

3600 3300 3600 4000 3600 3600 3600

E

32500

D

C

1 2 3

4 5

6 7 8

9 10

+ 3.600

B

3600

3600 3300 3600 4000

3600

3600

3600

32500

3600

1 2 3 4

5 6 7 8 9 10

Trang

1

E

D

+ 7.200

C

B

3600

3600

32500

3600 3300 3600 4000 3600 3600 3600

1 2

3 4 5 6 7 8 9

+

13.000

M

10

SN

+ 10.800

700

+ 7200

S

S

+ 3.600

±

0.000

S S

N N

6500 2200 5400

14100

B C D

E

SN

S

M

N

T r a n g

2

C                                           ơ

s                                           ở                                           tính                                           toán:

Quy

chu

n

xây

d

ng

Vi

t

Nam.

TCVN

2737­1995:

T

i

tr

ng

tác

độ

ng

Tiêu

chu

n

thi

ế

t

k

ế

.

TCVN

5574­2012:

K

ế

t

c

u

bêtông

bêtông

c

t

thép

Tiêu

chu

n

thi

ế

t

k

ế

.

Các

ti

u

chu

n

quy

ph

m

hi

n

hành

liên

quan

Quy

trình

tính

toán

thi

ế

t

k

ế

đượ

c

th

c

hi

n

theo

7

b

ướ

c

sau:

1.

Gi

i

thi

u

t

k

ế

t

c

u:

K                                           ế

t

c                                           ấ

u

ch                                           ị

u

l

c

h                                           ệ

khung

BTCT                                           đổ

toàn

kh                                           ố

i

liên

k                                           ế

t

c                                           ứ

ng

t                                           ạ

i

nút,

liên

k                                           ế

t

gi                                           ữ

a

c

t

v

i

móng

đượ

c

xem

ngàm

t

i

m

t

móng.

H

khung

ch

u

l

c

c

a

công

trình

m

t

h

không

gian,

th

xem

đượ

c

t

o

nên

t

nh

ng

khung

ph

ng

làm

vi

c

theo

hai

ph

ươ

ng

vuông

góc

v

i

nhau

ho

c

đ

an

chéo

nhau.

Tính

toán

h

khung

đượ

c

th

c

hi

n

theo

s

ơ

đồ

khung

ph

ng

theo

ph

ươ

ng

c

nh

ng

n

c

a

công

trình

+

h

d

m

d

c.

Công

trình

khung

bêtông

c

t

thép

toàn

kh

i

3

t

ng,

3

nh

p.

Để

đơ

n

gi

n

tính

toán,

tách

khung

ph

ng

tr

c

8,

b

qua

s

tham

gia

ch

u

l

c

c

a

c

a

h

gi

ng

móng

k

ế

t

c

u

t

ườ

ng

bao

che.

M

t

b

ng

k

ế

t

c

u

d

m

sàn

đượ

c

b

trí

nh

ư

trên

hình

v

sau:

D12

D18

E

E

S3

S3 S6

S6

D11

D13

D

D17

D

S2

S2 S5

D10

S5

C

D16

C

S1

S1 S4

S4

D9

1800

1800

B

B

D15

3600

3600 700

3600 3600 3600 3600

9 10

7 8

9 10

2.Ch                                           ọ

7 8

n                                           v                                           ậ                                           t                                           li                                           ệ                                           u                                           và

s                                           ơ                                           b                                           ộ                                           ch                                           ọ                                           n                                           kích                                           th

ướ                                           c                                           ti                                           ế                                           t                                           di                                           ệ                                           n                                           các

c                                           ấ                                           u                                           ki                                           ệ                                           n

2.1.

Ch

n

v

t

li

u

a.

Bêtông

­

Dùng

bêtông

c                                           ấ

p                                           độ

b

n

B20

(t                                           ươ

ng                                           đươ

ng

­

Kh

i

M250)

l

ượ

ng

riêng:

g

=

2500(

daN

/

bt

m

3

)

­

C

ườ

ng

độ

ch

u

nén

tính

toán:

R

=

115(

daN

b

/

cm

2

)

T r a n g

3

­

C

ườ

ng

độ

ch

u

kéo

tính

toán:

R

=

9(

daN

bt

/

cm

2

)

­

đ

un

đ

àn

h

i:

E

=

2.7

·

5

10

(

daN

/

2

cm

)

b.

C

t

thép

­

Thép

CI:                                           ϕ

<

+

10(mm)

C

ườ

ng

độ

ch

u

nén,

kéo

tính

toán:

R

=

R

s

=

2250(

daN

/

sc

cm

2

)

+

C

ườ

ng

độ

ch

u

c

t

khi

tính

toán

c

t

ngang:

R

s

=

w

1750(

daN

/

cm

2

)

+

đ

un

đ

àn

h

i:

E

=

2.1

·

6

10

(

daN

/

2

cm

)

­

Thép

CII:

≥ϕ

10(mm)

+

C

ườ

ng

độ

ch

u

nén,

kéo

tính

toán:

R

s

=

R

=

2800(

daN

sc

/

cm

2

)

+

C

ườ

ng

độ

ch

u

c

t

khi

tính

toán

c

t

ngang:

R

s

w

=

2250(

daN

/

cm

2

)

+

đ

un

đ

àn

h

i:

E

=

2.1

·

6

10

(

daN

/

2

cm

)

2.2.

Ch                                           ọ

n

s                                           ơ

b                                           ộ

kích

th                                           ướ

c

ti                                           ế

t

di                                           ệ

n

a.

Ch

n

chi

u

dày

c

a

sàn.

Chi                                           ề

u

dày

c                                           ủ

a

sàn

đượ

c

ch                                           ọ

n

d                                           ự

a

theo

công

th                                           ứ

c:

h

=                       D

b

m

1

l

Trong                                           đ                                           ó:

+

D

=

0.8

÷

1.4

ph

thu

c

vào

t

i

tr

ng,

t

i

tr

ng

l

n

thì

l

y

D

l

n

ng

ượ

c

l

i.

+

B

n

lo

i

d

m

l

y

=

m

30

35

+

B

n

4

c

nh

l

y

=

m

40

45

+

l

:

C

1

nh

ng

n

c

a

ô

b

n

Ch

n

chi

u

dày

b

n

cho

ô

sàn

l

n

nh

t

kích

th

ướ

c;

l

·

1

l

=

4.0

·

2

6.5(

m

)

ch

n

D=

1;

m

=

40

h                                           b                                                 D

=

(cid:222)

m

40

Để

thu

n

1

ti

n

cho

thi

công,

các

ô

b

n

còn

l

i

đề

u

ch

n

chi

u

dày

h

b                                           =100(

mm

)

Ch

n

chi

u

dày

sênô

h

=80(

mm

)

b

b.

Ch

n

kích

th

ướ

c

ti

ế

t

di

n

c

a

d

m

Ti                                           ế

t

di

n

các

d                                           ầ

m,

ph                                           ụ

thu                                           ộ

c

ch                                           ủ

y                                           ế

u

vào

nh                                           ị

p

d                                           ầ

m

và                                           độ

l                                           ớ

n

c

a

t                                           ả

i

tr                                           ọ

ng.

Theo

kinh

nghi

m

ti

ế

t

di

n

d

m

đượ

c

ch

n

theo

công

th

c:

+

h

d

m

=

1

i

d

ớ l

(v

m

m

12÷20,

ph

d

=

=

m

m

8÷15)

khung

+

b

=

(0.3

d

0.5)

h

d

T r a n g

4

b.1.                                           D                                           ầ

m                                           khung                                           tr                                           ụ                                           c                                           8

Nh                                           ị

p

BC:

D                                           ầ

m

D2,

D6

+

T

ng

2,3,

mái.

1

1

(cid:230)

(cid:246)

Ł

15

8

ł

Ch

n

kích

th

ướ

c

d

m

nh

p

BC

cho

t

ng

2,3,

mái

là:

·

(20

55)

cm

Nh

p

CD:

D

m

D2,

D6

+

T

ng

2,3,

mái.

1

(cid:230)

1

Ł

15

(cid:246)

8

ł

Ch

n

kích

th

ướ

c

d

m

nh

p

CD

cho

t

ng

2,3,

mái

là:

(20

·

30)

cm

Nh

p

DE:

D

m

D2,

D6

+

T

ng

2,3,

mái.

1

1

(cid:230)

(cid:246)

Ł

15

8

ł

Ch

n

kích

th

ướ

c

d

m

nh

p

CD

cho

t

ng

2,3,

mái

là:

·

(20

55)

cm

b.2.

D

m

d

c

Tr                                           ụ

c

B,

C,

D,

E.

D                                           ầ

m

D9                                           đế

n

D12,

D15                                           đế

n

D18

+

T

ng

2,3,

mái:

1

1

(cid:230)

(cid:246)

Ł

20

12

ł

Ch

n

kích

th

ướ

c

d

m

d

c

t

ng

2,3,

mái

là:

(20

·

30)

cm

c.

Ch

n

s

ơ

b

ti

ế

t

di

n

c

t

­

V                                           ề

độ

b                                           ề

Di

n

n:

di

tích

n

ti

ế

c

t

t

xác

A

đị

nh

đượ

c

0

theo

công

th

0

=

c:

k

A

R

N

Trong                                           đ

b

ó:

k

=

1.1÷1.5;

H

s

k

đế

n

nh

h

ưở

ng

c

a

mômen

u

n,

độ

m

nh

c

a

c

t,

hàm

l

ượ

ng

c

t

thép,

l

y

tùy

thu

c

vào

v

trí

c

a

c

t.

Khi

nh

h

ưở

ng

c

a

mômen

thì

l

y

k

ng

ượ

c

l

R

i.

b

=

115(

daN

/

cm

2

)

:

C

ườ

ng

độ

ch

u

nén

tính

toán

c

a

bêtông.

N

:

L

c

d

c

trong

c

t,

đượ

c

tính

toán

theo

công

th

c

g

n

đ

úng

nh

ư

sau:

N

=

qS

xq

(

kN

/

m

2

)

q

:

T

i

tr

ng

t

ươ

ng

đươ

ng

tính

trên

m

i

mét

vuông

m

t

sàn

trong

đ

ó

g

m

t

i

tr

ng

th

ườ

ng

xuyên

t

m

th

i

trên

b

n

sàn,

tr

ng

l

ượ

ng

d

m,

t

ườ

ng,

c

t

đ

em

tính

ra

phân

b

đề

u

trên

sàn.

Thông

th

ườ

ng

v

i

nhà

chi

u

dày

sàn

(10÷14)

cm

,

ít

t

ườ

ng,

kích

th

ướ

c

c

t

d

m

l

y

q

=

(10

14)

kN

/

2

m

.

Trang

5

S

n

tích

T

m

ng

t

di

xq                                           :

sàn

truy

ng

n

lên

t

c

i

t

tr

đ

)

ang

xét

(xem

hình

D

C

v

s xq

s

xq

B

D

C

B

B1/ 2

B1/2

B2/2

B1/2

B1/2

B2/2

B1

B2/2 B2/2

B2 B1

B2

7 8 9

7 8

­

9

Ki                                           ể                                           m                                           tra                                           v                                           ề                                           độ                                           ổ

n                                           đị                                           nh,                                           đ                                           ó                                           là                                           vi                                           ệ

c                                           h                                           ạ                                           n                                           ch                                           ế                                           độ                                           m                                           ả

nh                                           λ                                           .

l

b

Th

c

hi

n

ch

n

ti

ế

t

di

n

cho

c

t

tr

c

C

t

ng

1

c

a

khung

tr

c

8.

+

V

độ

b

n:

+

+

2

2

º Ł

ł

Ł

2

2

ł

ß

L

y

q

=

10(

kN

/

2

m

)

(cid:222)

N

=

10

·

46.98

=

469.8(

kN

)

k

1.2

Ch

(cid:222)

=

n

A

0

=

k

b

N

R

469.8

11500

Ch

n

s

ơ

b

ti

ế

t

di

n

c

t

là:

(20

×

35)

2

cm

+

Ki

m

tra

v

độ

n

đị

nh:

y

l

H

·

0.7

4.8

b

b

0.2

Đố

i

v

i

khung

nhà

nhi

u

t

ng

liên

k

ế

t

c

ng

gi

a

d

m

c

t

t

2

nh

p

tr

lên,

đổ

bêtông

c

t

thép

toàn

kh

i

h

s

y

=

0,

7

V

i

các

c

t

còn

l

i

vi

c

ch

n

kích

th

ướ

c

s

ơ

b

c

a

ti

ế

t

di

n

đượ

c

th

c

hi

n

t

ươ

ng

t

th

hi

n

b

ng

sau:

T r a n g

6

20

20

x

x

55

55

20

x

30

20

30

x

55

20

20

x

x

55

20

20

x

x

30

55

20

+ 10.800

x

55

+

7.200

±

0.000

+

- 1.200

3.600

6500 2200 5400

14100

B

C

D

E

3.L

p

s

ơ

đồ

tính

khung

ngang

Tính

toán

khung

ngang                                           đượ

c

th                                           ự

c

hi                                           ệ

n

theo

s                                           ơ                                           đồ

khung

ph                                           ẳ

ng

theo

ph                                           ươ

ng

c                                           ạ

nh

ng

n

c

a

công

trình

(ph

ươ

ng

độ

c

ng

độ

n

đị

nh

kém

h

ơ

n).

hình

hóa

k

ế

t

c

u

khung

thành

các

thanh

đứ

ng

(c

t)

các

thanh

ngang

(d

m),

liên

k

ế

t

c

ng

v

i

nhau

t

i

các

nút

liên

k

ế

t

gi

a

c

t

v

i

móng

ngàm

t

i

m

t

móng.

Trang

7

Khung                                           đượ                                           c                                           tính

theo                                           s                                           ơ                                           đồ                                           đ                                           àn                                           h                                           ồ

i,                                           để                                           đơ                                           n                                           gi                                           ả                                           n                                           l                                           ấ

y                                           nh                                           ị                                           p                                           tính                                           toán                                           b                                           ằ

ng                                           nh                                           ị                                           p                                           ki                                           ế                                           n

trúc.

Ta

s

ơ

đồ

tính:

D4

D7 D8 D9

D5

D6

6500

2200

5400

D1 D2 D3

14100

4.

B

Xác

C

đị

D

nh

E

các

tr

lo

ng

i

tác

t

d

i

ĩ ng

nh

lên

t

khung

i

4.1.

T

+

10.800

+

3.600

+

7.200

±

0.000

1.200

-

T r a n g

8

ý:

Chú

­

T                                           ả

i

tr                                           ọ

ng

b                                           ả

n

thân

c

a

các

k

ế

t

c

u

d                                           ầ

m

khung,

c                                           ộ

t

khung

nên

để

cho

ch

ươ

ng

trình

tính

toán

k

ế

t

c

u

t

tính.

­

Vi

c

tính

toán

t

i

tr

ng

vào

khung

đượ

c

th

hi

n

theo

hai

cách:

+

Cách

1:

Ch

ư

a

quy

đổ

i

t

i

tr

ng

(

gi

nguyên

d

ng

truy

n

t

i

).

+

Cách

2:

Quy

đổ

i

t

i

tr

ng

thành

phân

b

đề

u

v

i

h

s

quy

đổ

i

k.

V

i

t

i

tr

ng

phân

b

tác

d

ng

hình

thang.

Để

quy

đổ

i

sang

d

ng

t

i

tr

ng

phân

b

hình

ch

nh

t

ta

c

n

xác

đị

nh

h

s

chuy

n

đổ

i

k

nh

ư

l

1

sau:

2 q

2

=

k.g

s                                           .l

q

1                                           /2

l 2 l 2

k=1­2

β

2

i

+

β

b

3

=

v

2

l

l

1

2

V

i

ô

b

n

kích

th

ướ

c

l

1

2                                           =3.6×6.5(m);

×l

b

Tính

=                 3

5

.                                           6

=

6

2

·

0

.

.

1

277 k

-

=

(cid:222)

0

2

2 .

.

·

+

277

277

3

0

0

868

=

V

.

i

ô

b

n

kích

th

ướ

c

l

1

×l

=3.6×5.4(m);

2

Tính

= b                 3

.                                           6

4

5 =

2

0

·

.

.

1

333 k

-

=

(cid:222)

0

2

2 .

.

·

+

333

333

3

0

0

815

=

V

.

i

ô

b

n

kích

th

ướ

c

l

1

×l

=2.2×3.6(m);

2

b

Tính

=                 2

.                                           2

6

3 =

2

0

·

.

.

1

306 k

-

=

(cid:222)

0

2

2 .

.

·

+

306

306

3

0

0

842

=

V                                           ớ                                           i

.

t                                           ả                                           i                                           tr                                           ọ                                           ng                                           phân                                           b                                           ố

có                                           d                                           ạ                                           ng                                           tam                                           giác.                                           Để

quy                                           đổ                                           i                                           sang                                           d                                           ạ                                           ng                                           t

ả                                           i                                           tr                                           ọ                                           ng

5

8

2

q

l

l 1

1

(cid:215)

g

k

q

s

=

(cid:215)

1

l

2

T r a n g

9

c.1.T                                           ĩ                                           nh                                           t                                           ả                                           i                                           t                                           ầ                                           ng                                           2,

6500 2200 5400

3

7

s                                           =

372

g

=

daN/m

2

372

g

daN/m

2

s

372

g

daN/m

2

=

s

2 0 0

8

d

mm

d

t                                           =

t                                           =

200

200

mm

g

s                                           =

372

daN/m

2

g

s                                           =

372

daN/m

2

9

458.4

g

g

daN/m

=

t

2

s

372

=

2

daN/m

g

ht

ht

g

G                                           B                                           G                                           C                                           G                                           D                                           G                                           E

Cách                                           1

g

t1

B

G

g

1

tg                                           g

t2

g

G                                           E

Cách                                           2

G                                           C                                           G                                           D

g

3

6500 2200 5400

B

C

D

E

T                                           Ĩ                                           NH

T                                           Ả                                           I                                           PHÂN                                           B                                           Ố                                           ­                                           daN/m

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Tr

ng

l

ượ

ng

t

ườ

ng

200

xây

trên

d

m

cao:

(3.6

­

0.55)

=

3.05(

m

)

g

t1

=

458.4

×

3.05

1398.1

2.                                           T                                           ả                                           i                                           tr                                           ọ                                           ng

t                                           ừ                                           sàn                                           S1                                           truy                                           ề                                           n

vào                                           d                                           ướ                                           i                                           d                                           ạ                                           ng                                           hình

thang                                           v                                           ớ                                           i                                           tung                                           độ

l                                           ớ                                           n                                           nh                                           ấ                                           t:

g                                           1

2

g

=

g 2

ht

×

372

=

×

1339.2

Đổ

3.6/2

b

i

ra

đề

phân

u

v

=

0.868

i:

k

1339.2

×

C

0.868

ng

1162.4

2560.5

ng

1.

l

Tr

ượ

ng

ng

200

t

ườ

xây

m

trên

cao:

d

(3.6

=

­

3.05(

0.55)

m

= )

458.4 g

t2

×

2.

T

3.05

i

1398.1

tr

sàn

ng

S3

t

truy

d

ướ

n

i

d

vào

v

ng

hình

i

thang

tung

nh

độ

l

t:

n

g

ht

×

=

372

2

×

1339.2

Đổ

3.6/2

i

ra

=

phân

u

b

v

i:

đề

k

1339.2

=

×

0.815

0.815

1091.4

2489.6

C

Trang

ng

10

1.

Lo                                                                               ạ

T

K/qu

1.

1.

1.

1.

c.2.                                           T

ĩ                                           nh                                           t                                           ả                                           i                                           t                                           ầ                                           ng                                           mái

6500 2200 5400

7

g

g

s                                           =

372

=

daN/m

2

s

372

g

daN/m

=

2

372

s

2

daN/m

200

mm

8

t                                           =

200

d

mm

d

200

g

s

t                                           =

=

372

daN/m

2

g

s                                           =

372

daN/m

2

9

=

g

t

=

458.4

372

g

daN/m

2

daN/m

s

2

g

ht

ht

g

G                                           B                                           G                                           C                                           G                                           D                                           G                                           E

g

g

1

t1

Cách                                           1

B

G

tg                                           g

t2

g

C                                           G                                           D                                           G                                           E

G

Cách                                           2

g

3

6500 2200 5400

B

C

D

E

Để

tính

toán

t

i

tr

ng

t

ĩ

nh

phân

b

đề

u

trên

mái

tr

ướ

c

h

ế

t

ta

ph

i

xác

đị

nh

kích

th

ướ

c

quy

đổ

i

c

a

t

ườ

ng

thu

h

i

xây

trên

mái.

D

a

vào

m

t

c

t

ki

ế

n

trúc,

ta

di

n

tích

t

ườ

ng

thu

h

i

xây

trên

nh

p

BC

là:

1

2

Nh

ư

v

y

n

ế

u

coi

t

i

tr

ng

t

ườ

ng

phân

b

đề

u

trên

nh

p

BC

thì

t

ườ

ng

chi

u

cao

trung

bình

là:

S

th

6.08

l

1

6.5

BC

Tính

toán

t

ươ

ng

t

cho

nh

p

CD,

trong

đ

o

n

này

t

ườ

ng

chi

u

cao

trung

bình

b

ng(

b

qua

l

c

a

xem

nh

ư

m

t

m

ng

t

ườ

ng

đặ

S

c)

th

4.48

3

l

2.2

CD

Tính

toán

t

ươ

ng

t

cho

nh

p

DE,

đượ

c

chi

u

cao

trung

bình

S

là:

th

4.91

2

l

5.4

DE

Trang

12

Lo

T

1.

1.

1.

T

Lo

1.

4.Thành

1.

1.

1.

Tr

an

g

14

S                                           ơ                                           đồ                                           t                                           ĩ                                           nh                                           t

ả                                           i                                           tác                                           d                                           ụ                                           ng                                           vào                                           khung

(bi                                           ể                                           u                                           di                                           ễ                                           n                                           theo                                           cách

2):

2753.8                                           1593.3

7348.4                                           2560.5

7348 .4

2753.8

2560.5

1489

8588.4

2964.3                                           2964.3

511.5

8588.4

8588.4

7348.4

8588.4

7348.4

511.5

+ 7.200

+

10.800

+

3.600

±

0.0 00

-

1.2 00

6500 2200 5400

14100

B

C

D

E

S

Ơ

ĐỒ

T

Ĩ

NH

T

I

TÁC

D

NG

VÀO

KHUNG

(

daN;

daN/m

)

4.2.                                           Xác                                           đị                                           nh                                           ho

ạ                                           t                                           t                                           ả                                           i                                           đứ                                           ng                                           tác

d                                           ụ                                           ng                                           vào                                           khung

Ho

t

t

i

s

d

ng

đượ

c

l

y

theo

tiêu

chu

n

TCVN

2737­1995

a.

Ho

t

t

i

đơ

n

v

Tr an g

15

b.                                           Tính

tr                                           ườ                                           ng                                           h                                           ợ                                           p                                           ho                                           ạ                                           t                                           t

6500 2200 5400

ả                                           i                                           1

7

s                                           =

372

g

=

daN/m

2

372

g

daN/m

2

s

372

g

daN/m

s

2

=

=

200

8

200

mm

t

d

200

d

mm

t                                           =

g

s                                           =

372

daN/m

2

g

s                                           =

372

daN/m

2

9

=

g

t

458.4

372

g

daN/m

daN/m

2

=

s

2

g

ht

ht

G

g

Cách

B                                           G                                           C                                           G                                           D                                           G                                           E

1

1

g

t1

B

g

G

tg                                           g

t2

g

C                                           G                                           D                                           G                                           E

G

Cách                                           2

g

3

6500 2200 5400

B

C

D

E

HO

T

T

I

T

NG

2

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Do

ho

t

t

i

t

sàn

S1

truy

n

vào

d

ướ

i

d

ng

hình

thang

tung

độ

l

n

nh

t:

p

1ht

=

2

×

240

×

3.6/2

=

p                                       1

1

864.0

2

p

C

i

phân

b

Đổ

ra

i:

v =

đề

0.868

u

k

864.0

= ×

750.0

da N/ m

C

0.868

)

75 0(

ng Do

t

1.

t

ho

ả 750.0

truy

ề i

S3

n

t

sàn

vào

hình

d

thang

ng

ướ d

i

n

tung l

t:

p ớ                  độ

nh

1ht

×

24

0

=

3.6/2

×

=

2

i b

864.0

ph

ân

đề

Đổ

ra

u

i: 0.815

v

=

864.0

k

×

0.815

da N/ m

C

=

)

ng

704.2(

70 4. 2

ho

t

Do

704.2

i

1.

t

sàn

t n

tru

y

vào

S1

2×5/8×(240

× =

da N 972.0

C

3.6/2)×3. 6/2

)

97 2(

ng Do ạ

t

1.

t

ho

ả 972.0

truy

ề i

S3

n

sàn

t

vào

P                                           1D                                           =P                                           1E

2×5/8×(240                                           ×

)                                           972.0

C

3.6/2)×3.6/2                                           =                                           972                                           (                                           daN

Trang ng

16

972.0

7

6500 2200

5400

p

=

2

360

daN/m

2 0 0

8

1

9

Cách

Cách

2

P

P

1

D

P

P

1

D

3

p

6500 2200 5400

B

C

D

HO                                           Ạ

E

T                                           T                                           Ả                                           I                                           1­                                           T                                           Ầ                                           NG

3

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.                                           Do

ho                                           ạ                                           t                                           t                                           ả                                           i                                           t                                           ừ

sàn                                           S2                                           truy                                           ề                                           n                                           vào

d                                           ướ                                           i                                           d                                           ạ                                           ng                                           tam                                           giác

v                                           ớ                                           i                                           tung                                           độ                                           l                                           ớ

n

nh                                           ấ                                           t:

p

3

P

p

1C

=P

1D

=

1tg

2

×

×

2.2/2

360

=

ra

792.0

phân

Đổ

b

i

đề

i:

u

k

v

=

5/8

=

792.0

495.0(

×

daN/m

5/8

)

ng

495.0

495.0

C

1.

t

Do

t

ho

i

S2

t

ừ truy

sàn

n

×

vào

2.2/2)×3.6/2

2×0.842×(360

=

)

1200.4

1200.4

(

daN

C

1200.4

ng

Tr an g

17

700

700

6500 2200 5400

7

p                                           =                                           97.5                                           daN/m

2

p                                           =                                           97.5                                           daN/m                                           2

8

p

=                                           97.5                                           daN/m                                           2

p                                           =                                           97.5                                           daN/m                                           2

9

p

ht

1

p

P                                           1

ht

Cách

1

p

p

1

Cách

2

2

6500

2200

5400

B

C

D

E

HO                                           Ạ

T

T                                           Ả

I

T                                           Ầ

NG

MÁI

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Do

ho                                           ạ

t

t                                           ả

i

t                                           ừ

sàn

S4

truy                                           ề

n

vào

d                                           ướ

i

d                                           ạ

ng

hình

thang

v                                           ớ

i

độ

tung

l                                           ớ

n

nh                                           ấ

t:

p

1ht

=

2

×

97.5×

3.6/2

=

351

2

p

1

P

1B

=P

p

1E

1C

P

1D

=P

phân                                           b                                           ố                                           đề                                           u

Đổ                                           i                                           ra

=                                           0.868

351

v                                           ớ                                           i:                                           k ×

(

0.868

daN/m

)

=

304.7

304.7

304.7

C

1.

ng

Do

ho ả

ạ i

t

t

t ừ

sàn

n

S6

vào

truy

d ạ

ướ ng

i

hình

d

thang

tung

v

độ

l

i

n

p

nh 1ht

=

t:

×

2

3.6/2

×

=

97.5

351

Đổ phân

i

b

ra

v

đề

i:

u

k

351

=

×

0.815

0.815

=

)

286.1

286.1

(

C

daN/m

1.

ng

Do

ho

286.1

t

t

t ừ

sàn

i

S4

vào

truy

2×5/8×(97.5

n

×

(

3.6/2)×3.6/2

daN/m

)

=

394.9

394.9

394.9

C

1.

ng

Do

ho ả

ạ i

t

t

t ừ

sàn

n

S3

vào

truy

2×5/8×(97.5

=

×

394.9

3.6/2)×3.6/2

(

daN

C

)

ng

394.9

394.9

Trang                                           18

c.                                           Tính                                           tr                                           ườ                                           ng                                           h                                           ợ

p                                           ho                                           ạ                                           t                                           t                                           ả                                           i                                           2

6500 2200 5400

7

2

p                                           =                                           360

daN/m

20 0

8

1

9

Cách

Cách

2

p

P

C

tg

P

3

p

6500

D

2200 5400

B

C

D

E

HO

T

T

I

2

­

T

NG

2

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Do

ho

t

t

i

t

sàn

S2

truy

n

vào

d

ướ

i

d

ng

tam

giác

v

i

tung

độ

l

n

nh

t:

p

2tg

=

2

×

360

×

2.2/2

=

792.0

3

1                     p

i

phân

D

b

Đổ

đề

ra

i:

=

792.0

u

v

× k

ớ 5/8

5/8

)

49 5.0

=

ng

495.0(

C

495.0

daN/m

1.

i

t

t

Do

t ừ

ho

×(360

sàn

o

×

S2

n

2.2/2)×3.6/2=

truy

0.8

42

)

1200.4

12

00.

4

ng

(

daN

C 1200.4

Tr an g

19

6500 2200 5400

7

p                                           =                                           240                                           daN/m

2

p                                           =                                           240

2

daN/m

200

8

p                                           =

240                                           daN/m

2

p                                           =                                           240                                           daN/m

2

9

p

ht

2

2

P

ht

Cách

p

1

=750

p

P                                            B                                            =972

=972

P                                            C

1

P                                           D

2

=704.2

=972

=972

p

P

Cách                                           2

2

6500

2200

5400

B

C

D

E

HO                                           Ạ                                           T

T                                           Ả                                           I                                           2                                           ­                                           T                                           Ầ                                           NG                                           3

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Do

ho

t

t

i

t

sàn

S1

truy

n

vào

d

ướ

i

d

ng

hình

thang

v

i

tung

độ

l

n

nh

t:

p

2ht

=

2

×

240

×

3.6/2

=

864.0

2                                     p                                           1

C

p

2

b              ra

Đổ

ph ân

i

u                                           v                                           ớ                                           i:                                           k

đề

86 4.0

(

=

daN/m

0. 86 8= 75 0

)

0.868

×

750.0

ng

75 0.0 Do

C

ho

ạ 1.

t

sàn

i

S3

t

truy

t

d

n

i

d

ng

hình

vào

ướ

thang

tu

ng

l

i

v

n

độ

2

nh

×

p                 ấ

=

240

t:

2ht

×

=

ra

Đ ổ

3.6/2

phân

86

4.0

b i

i:

=

v

0.815

đề

ớ       k

864.0 u

704.2

)

×

(

C

0.815=7 04.2

da N/ m

ng

t

1.

t

ho

ả 704.2

Do

ừ truy

i

S1

n

t

sàn

vào

972.0

2×5/8×( 240 )

3.6 /2) ×3. 6/2 =9 72(

C

×

da N

ng

t

1.

t

ho

ả 972.0

Do

ừ truy

i

S3

n

t

sàn

vào

P                                           2D                                           =P                                           2E

2×5/8×(240                                           ×

972.0

C

3.6/2)×3.6/2=972                                           (                                           daN                                           )

ng

Trang

20

972.0

B

C

700

E

700

D

7

p                                           =                                           97.5                                           daN/m

2

p                                           =                                           97.5                                           daN/m

2

p                                           =                                           97.5                                           daN/m

2

8

9

2

Cách

1

Cách

p

B

tg

P

P

C

2

P

p

P

3

D

6500 2200 5400

B

C

D

E

HO                                           Ạ

T

T                                           Ả                                           I                                           2­                                           T                                           Ầ                                           NG

MÁI

K.hi

u

Lo

i

t

i

tr

ng

cách

tính

K/qu

1.

Do

ho

t

t

i

t

sàn

S5

truy

n

vào

d

ướ

i

d

ng

tam

giác

v

i

tung

độ

l

n

nh

t:

p

2tg

=

2

×

97.5

×

2.2/2

=

214.5

3

2

p

Đ ổ

D

ra                                           phân                                           b                                           ố

i

đề

214.5

=               i:                        u

×

v                     5/              8               k

5/8

da N/ m

C

=

)

ng

134.1(

13 4.1

Do

t 134.1

1.

i

t

ho

t

n

tru

y

vào

S2

sàn 2×0.842×(97.5

= ×

)

(

325.1

2.2/2)×3. 6/2

32 5.1

da N

C

ho

ạ 32 5.1

ng

t

Do

t

1.

truy

t

n

i

vào

E

2

×

97.5

2

)

×

=

0.6

210.6

210.6

×

(

3.6/2

daN

C

210.6

ng

Tr an g

21

đồ

ho

S                                           ơ

t

(bi

u

di

t                                           ả                                           i                                           tác                                           d                                           ụ                                           ng                                           vào                                           khung

394.9

394.9

n                                           theo                                           cách                                           2):

495

394.9                                           394.9

+

10.800

7.200

+

972                                       750

972                                           972

972

+ 3.600

± 0.000

- 1.200

6500

2200

5400

14100

B C D E

S                                           Ơ                                           ĐỒ                                           HO                                           Ạ                                           T                                           T                                           Ả                                           I

1                                           TÁC                                           D                                           Ụ                                           NG                                           VÀO                                           KHUNG

(                                           daN;                                           daN/m                                           )

210.6

325.1

210.6

+ 10.800

325.1

134.1

1

2

0

0.

972                                           972                                           972                                           972

4

1

2

0

0.

4

+ 7.200

+ 3.600

± 0.000

-

1.200

6500

2200

14100

5400

B C D E

S                                           Ơ

ĐỒ                                           HO                                           Ạ                                           T                                           T                                           Ả                                           I                                           2

TÁC                                           D                                           Ụ                                           NG                                           VÀO                                           KHUNG                                           (                                           daN;

daN/m                                           )

Tr an g

22

4.3.

Xác                                           đị                                           nh                                           ho                                           ạ                                           t                                           t                                           ả

i                                           gió                                           tác                                           d                                           ụ                                           ng                                           vào                                           khung

Xác

đị

nh

theo

TCVN

2737­1995,

T

i

tr

ng

tác

độ

ng

­

Tiêu

chu

n

thi

ế

t

k

ế

.

Công

trình

xây

d

ng

t

i

thành

ph

Tuy

Hòa,

t

nh

Phú

Yên,

thu

c

vùng

gió

III.B,

áp

l

c

gió

đơ

n

v

(

B

ng

4

TCVN

2737­1995)

W

=

125(

daN

0

/

m

2

)

thu

c

d

ng

đị

a

hình

B.

Công

trình

cao

d

ướ

i

40m

nên

ta

ch

xét

đế

n

tác

d

ng

t

ĩ

nh

c

a

t

i

tr

ng

gió.

Giá

tr

tiêu

chu

n

thành

ph

n

t

ĩ

nh

c

a

t

i

tr

ng

gió

W

độ

cao

Z

so

v

i

m

c

chu

n

đượ

c

xác

đị

nh

theo

công

th

W

=

W

c:

·

k

·

c

0

Trong

đ

W

ó:

:

0

giá

tr

c

a

áp

l

c

gió

l

y

theo

b

ng

đồ

phân

vùng

ph

l

c

D

c

a

tiêu

chu

n.

k

:

H

s                                           ố

tính                                           đế

n

s

thay                                           đổ

i

c                                           ủ

a

áp

l                                           ự

c

gió

theo

độ

cao

so

v                                           ớ

i

m                                           ố

c

chu                                           ẩ

n

(xác

đị

nh

theo

b

ng

G

TCVN­2737­1995)

d

ng

đị

a

hình

(b

ng

5

TCVN­2737­1995)

c:

H

s

khí

độ

ng

(b

ng

6

TCVN­2737­1995)

Phía

đ

ón

gió

c

=

+0.8

Phía

khu

t

gió

c

=

­0.6

T

i

tr

ng

tính

toán

c

a

gió

truy

n

lên

khung

đượ

c

tính

theo

công

th

q

c:

=

nk

d

W

i

c

0

B

q

d

=

h

nk

W

i

c

0

B

h

Trong

đ

ó:

n

=

1.2

h

s

độ

tin

c

y

c

a

t

i

tr

ng

gió

B

:

Ph

m

vi

truy

n

t

T

i.

Ả                                           I                                           TR                                           Ọ                                           NG                                           GIÓ                                           TÁC                                           D                                           Ụ

NG                                           VÀO                                           KHUNG

(

daN/m

)

1

3.6

4.2

1.2

0.848

125

0.8

­0.6

3.6

366.3

­274.8

2

3.6

7.8

1.2

0.947

125

0.8

­0.6

3.6

409.1

­306.8

Chú                                           ý:

M                                           ố                                           c                                           chu                                           ẩ                                           n                                           để                                           xác

đị                                           nh                                           h                                           ệ                                           s                                           ố                                           k                                           đượ                                           c

l                                           ấ                                           y                                           ở                                           cao                                           trình                                           m

ặ                                           t                                           đấ                                           t                                           t                                           ự                                           nhiên                                           cách

m                                           ặ                                           t                                           n                                           ề                                           n                                           ở

cos

±0.00

0.6(

m

T

)

i

tr

ng

gió

trên

mái

quy

v

l

c

t

p

trung

đặ

t

đầ

u

c

t

S

,

S

đ

Để

h

an

toàn

h                                           ệ

s                                           ố

k

l                                           ấ

y                                           ở

cao

trình                                           đỉ

nh

mái

t                                           ứ

c

Z

=

13.6(

m

)

(cid:222)

k                           =

1.06

Hình

dáng

mái

h

s

khí

độ

ng

trên

mái

tham

kh

o

b

ng

6

c

a

TCVN

2737

1995

h

11.4

l

C

e2                                           =

e1                                           =

C

­0.607

14.1

­0.462

­0.462

C

C

e2                                           =

e1                                           =

­0.570

14°

14°

17°

17°

+0.8

+0.8

Trang

23

Tr                                           ị                                           s                                           ố

S                                           tính                                           theo                                           công                                           th                                           ứ                                           c

sau:

S

=

nkW

0

B

C

i

(cid:229)

i

=

1.2

·

h

1.06

·

125

·

3.6

C

i

h

i

=

(cid:229)

572.4

C

i

h

(cid:229)

i

+

Gió

th                                           ổ

i

t                                           ừ

trái

S

sang.

d

=

572.4

·

(0.8

·

0.5

-

0.607

·

2.2)

=

-

535.4(

daN

)

S

=

572.4

h

·

(0.6

·

0.5

+

0.462

·

2.2)

=

753.5(

daN

)

+

Gió

th

i

t

ph

i

S

sang.

=

d

572.4

·

(0.8

·

0.5

-

0.570

·

2.2)

=

-

488.8(

daN

)

S

=

572.4

h

·

(0.6

·

0.5

+

0.462

·

2.2)

=

753.5(

daN

)

535.4

753.5

441.5

+ 10.80

331.1

+

7.200

409.1

306.8

+

3.600

366.3

±

274.8

0.000

6500 2200 5400

- 1.200

B C

D E

S                                           Ơ                                           ĐỒ                                           GIÓ                                           TÁC

D                                           Ụ                                           NG                                           VÀO                                           KHUNG                                           –                                           GIÓ

TRÁI                                           (                                           daN;                                           daN/m                                           )

753.5

10.80

488.8

331.1

+

441.5

+ 7.200

306.8

409.1

+

274.8

366.3

3.600

0.000

±

6500 2200 5400

- 1.200

B C D

S                                           Ơ                                           ĐỒ                                           GIÓ                                           TÁC

E

D                                           Ụ                                           NG                                           VÀO                                           KHUNG                                           –                                           GIÓ                                           PH

Ả                                           I                                           (                                           daN;                                           daN/m                                           )

Tr an g

24

5.                                           Xác                                           đ

ị                                           nh                                           n                                           ộ                                           i                                           l                                           ự                                           c                                           và

t                                           ổ                                           h                                           ợ                                           p                                           n                                           ộ                                           i                                           l

ự                                           c

5.1.

Xác

đ

nh

n

i

l

c

S                                           ử

d                                           ụ

ng

ch                                           ươ

ng

trình

tính

toán

k                                           ế

t

c                                           ấ

u

SAP2000

đ                                           ể

tính

toán

n                                           ộ

i

l                                           ự

c

cho

khung

v                                           ớ

i

s

ơ

đồ

ph

n

t

d

m,

c

t

nh

ư

hình

v

sau.

Chú                                                       :                                           Vì                                           tr                                           ọ                                           ng

ý

l                                           ượ                                           ng                                           b                                           ả                                           n                                           thân                                           c                                           ủ

a                                           d                                           ầ                                           m                                           và                                           c                                           ộ                                           t                                           khung

ch                                           ư                                           a                                           tính                                           nên                                           khi                                           khai

báo                                           t                                           ả                                           i                                           tr                                           ọ                                           ng

trong

ch

ươ

ng

trình

tính

toán

k

ế

t

c

u,

v

i

tr

ườ

ng

h

p

t

ĩ

nh

t

i

ph

i

k

đế

n

tr

ng

l

ư

ng

b

n

thân

c

a

k

ế

t

c

u

(c

t,

d

m

khung)

v

i

h

s

v

ượ

t

t

i

n=1.1

Ta

các

s

li

u

đầ

u

vào

c

a

ch

ươ

ng

trình

tính.

B

ng

khai

báo

kích

th

ư

c

ti

ế

t

di

n:

(

Display

à

ShowTables

à

Model

à

Definition

à

ropertyDefinition

à

Frame

Section

Property)

Tr

an

g

25

T                                           ừ                                           ph                                           ầ                                           n                                           m                                           ề                                           m                                           SAP2000

ta                                           xu                                           ấ                                           t                                           các                                           s                                           ơ                                           đ

ồ                                           sau:

S                                           ơ                                           đ                                           ồ                                           b                                           ố

trí                                           kích                                           th                                           ư                                           ớ                                           c

Xu

t

s

ơ

ti                                           ế                                           t                                           di                                           ệ                                           n                                           cho                                           khung

tr

đ

ng:

t

(

View

i

à

Set

Display

Option…

à

)

S                                           ơ                                           đồ                                           t                                           ĩ                                           nh

t                                           ả                                           i                                           tác                                           d                                           ụ                                           ng                                           lên

khung

Tr an g

26

S                                           ơ                                           đ                                           ồ

ho                                           ạ                                           t                                           t                                           ả                                           i                                           1                                           tác

d                                           ụ                                           ng                                           lên                                           khung

S

ơ                                           đồ                                           ho                                           ạ                                           t                                           t                                           ả                                           i

2                                           tác                                           d                                           ụ                                           ng                                           lên                                           khung

Tr an g

27

S                                           ơ                                           đồ                                           gió                                           trái

tác                                           d                                           ụ                                           ng                                           lên                                           khung

S                                           ơ                                           đồ                                           gió                                           ph                                           ả                                           i                                           tác

d                                           ụ                                           ng                                           lên                                           khung

Tr an g

28

S                                           ố                                           li                                           ệ                                           u

đầ                                           u                                           ra                                           c                                           ủ                                           a                                           ch                                           ươ                                           ng

trình                                           tính                                           .

Bi                                           ể                                           u                                           đồ

bao                                           mômen                                           (                                           kN.m                                           )

Bi                                           ể

u                                           đồ                                           bao                                           l                                           ự                                           c                                           c                                           ắ

t                                           (                                           kN                                           )

Tr an g

29

B                                           ả

ng                                           giá                                           tr                                           ị                                           n                                           ộ                                           i                                           l

ự                                           c                                           (Display                           à                 Show                                           tables                           à                 Element

output                           à                 Frame                                           out                                           put)

Tr an g

37

5.2.T                                           ổ                                           h                                           ợ                                           p                                           n

ộ                                           i                                           l                                           ự                                           c

T

h

p

n

i

l

c

theo

TCVN

2737

1995(

Đ

i

u

2.4)

+

T

h

p

c

ơ

b

n

1:

T

ĩ

nh

t

i

+

1

tr

ườ

ng

h

p

ho

t

t

i

v

i

h

s

t

h

p

1

+

T

h

p

c

ơ

b

n

2:

T

ĩ

nh

t

i

+

2

tr

ườ

ng

h

p

ho

t

t

i

tr

lên

v

i

h

s

t

h

p

0.9

Trên

c

ơ

s

đ

ó

ta

c

u

trúc

t

h

p

nh

ư

sau:

TH1:

TT

+

HT1

TH2:

TT

+

HT2

TH3:

TT

+

GT

TH4:

TT

+

GP

TH5:

TT

+

0,9(HT1

+

HT2)

TH6:

TT

+

0,9(

HT1

+

GT)

TH7:

TT

+

0,9(HT1

+

GP)

TH8:

TT

+

0,9(

HT2

+

GT)

TH9:

TT

+

0,9(HT2

+

GP)

TH10:

TT

+

0,9(HT1

+

HT2+GT)

TH11:

TT

+

0,9(HT1

+

HT2+GP)

m

i

ti

ế

t

di

n

ph

i

xét

11

t

h

p

c

ơ

b

n

để

tìm

ra

các

c

p

n

i

l

c

nguy

hi

m

nh

ư

sau:

+ -

ộ                                           t:

+                                           Đố                                           i                                           v                                           ớ                                           i                                           c

-

M

t                                           ư

+

N

max

Riêng

đố

i

v

i

ti

ế

t

di

n

chân

c

t

t

h

p

thêm

Q

t

để

ph

c

v

ư

cho

vi

c

tính

móng.

Vi                                           ệ

c

t                                           ổ

h                                           ợ

p

n                                           ộ

i

l                                           ự

c

cho

d                                           ầ

m

c                                           ộ

t

đượ

c

trình

bày

thành

các

b                                           ả

ng.

+

V

i

ph

n

t

d

m:

t

h

p

n

i

l

c

cho

ba

ti

ế

t

di

n

(hai

ti

ế

t

di

n

đầ

u

d

m

m

t

ti

ế

t

di

n

gi

a

d

m)

+

V

i

ph

n

t

c

t:

t

h

p

n

i

l

c

cho

hai

ti

ế

t

di

n

(ti

ế

t

di

n

chân

c

t

ti

ế

t

di

n

đầ

u

c

t)

Tr an g

38

Ph                                           ầ

n

t

ế

Ti

t

di

n

NG

T

B

D

H

MÔ                ME Ợ N

M

KHUNG

P

h

ng ợ

Tr

p

ườ

t

ng

tr

(

i

đơ

v

KN.m)

n

Giá

men

tr

c

a

t

h

các ợ

p

n

v

(

KN.m

đơ

)

T

h

p

TT

GT

HT 2

GP

HT1

TH1

TH4

TH 3

TH5

TH2

TH6

TH9

TH10

TH 8

TH7

M

M

TH11

max

min

M

D1                                           0                                           ­58.35                                           ­13.79                                           ­1.62                                           50.18

ttoá n

­50.89                                           ­72.13                                           ­59.97                                           ­8.17                                           ­109.2                                           ­73.76                                           ­25.59                                           ­116.6                                           ­14.65

­105.6                                           ­27.05                                           ­118.0                                           ­118.01                                           ­8.17                                           ­118.01

D1

3.25

86.06

23.88

­1.60

3.12

­3.27

109.9

84.46

89.18

82.79

108.3

110.4

104.6

87.43

81.68

108.9

103.2

81.68

110.36

110.36

D1

­71.95

6.5

­17.67

­1.57

­43.93

44.35

­89.61

­73.52

­115.8

­27.60

­91.18

­127.4

­47.93

­112.9

­33.44

­128.8

­49.34

­128.80

­27.60

­128.80

D2

0

­20.65

­5.69

­0.80

17.25

­17.37

­26.34

­21.45

­3.40

­38.02

­27.14

­10.25

­41.40

­5.85

­37.00

­10.97

­42.12

­42.12

­3.40

­42.12

D2

­11.62

1.1

­3.99

1.78

0.32

­0.30

­15.61

­9.84

­11.30

­11.92

­13.83

­14.92

­15.48

­9.73

­10.29

­13.31

­13.88

­15.61

­9.73

­15.61

D2

­10.78

­2.29

2.2

­1.63

­16.60

16.76

­13.06

­12.40

­27.38

5.98

­14.69

­27.78

2.25

­27.18

2.85

­29.24

0.79

­29.24

5.98

­29.24/+5.98

D3

0

­42.62

­10.12

­1.71

46.40

­46.72

­52.74

­44.33

3.78

­89.35

­54.45

­9.97

­93.78

­2.40

­86.21

­11.50

­95.32

­95.32

3.78

­95.32/+3.78

D3

61.37

17.67

­1.44

2.7

­3.44

3.34

79.04

59.94

57.93

64.72

77.60

74.17

80.28

56.98

63.09

72.88

78.99

56.98

80.28

80.28

D3

­38.17

­9.23

­1.17

­53.29

5.4

53.41

­47.40

­39.34

­91.46

15.24

­48.57

­94.43

1.59

­87.18

8.85

­95.49

0.54

­95.49

15.24

­95.49/+15.24

D4

0

­61.61

­2.72

­13.02

23.96

­24.28

­64.33

­74.63

­37.65

­85.88

­77.35

­42.50

­85.91

­51.76

­95.18

­54.21

­97.63

­97.63

­37.65

­97.63

D4

84.31

­2.28

24.53

1.65

3.25

­1.64

82.03

108.8

85.96

82.67

106.7

83.75

80.79

107.9

104.9

105.8

102.9

80.79

108.83

108.83

D4

6.5

­72.19

­1.83

­17.15

­20.65

21.01

­74.01

­89.33

­92.84

­51.18

­91.16

­92.42

­54.93

­106.2

­68.71

­107.9

­70.36

­107.85

­51.18

­107.85

D5

0

­18.42

­0.19

­5.99

8.18

­8.34

­18.61

­24.41

­10.23

­26.76

­24.60

­11.22

­26.09

­16.45

­31.32

­16.62

­31.49

­31.49

­10.23

­31.49

D5

1.1

­10.85

2.07

­4.21

0.10

­0.13

­8.78

­15.06

­10.75

­10.98

­12.98

­8.89

­9.10

­14.55

­14.75

­12.68

­12.89

­15.06

­8.78

­15.06

D5

­11.48

2.2

­1.65

­2.42

­7.98

8.08

­13.13

­13.89

­19.45

­3.39

­15.54

­20.14

­5.69

­20.83

­6.38

­22.32

­7.86

­22.32

­3.39

­22.32

D6

0

­43.74

­2.11

­9.65

21.85

­22.15

­45.84

­53.39

­21.88

­65.88

­55.50

­25.97

­65.57

­32.76

­72.36

­34.65

­74.25

­74.25

­21.88

­74.25

D6

59.81

­2.01

2.7

18.17

­1.76

1.83

57.80

77.98

58.05

61.64

75.97

56.42

59.65

74.58

77.80

72.77

76.00

56.42

77.98

77.98

D6

­40.19

­1.90

­8.69

5.4

­25.36

25.81

­42.09

­48.88

­65.55

­14.39

­50.78

­64.73

­18.68

­70.84

­24.78

­72.55

­26.50

­72.55

­14.39

­72.55

D7

0

­29.29

­3.40

­2.38

3.19

­4.45

­32.68

­31.66

­26.10

­33.73

­35.06

­29.47

­36.35

­28.56

­35.43

­31.61

­38.49

­38.49

­26.10

­38.49

D7

63.44

11.62

­1.77

3.25

­0.86

0.43

75.06

61.67

62.58

63.87

73.29

73.12

74.28

61.08

62.24

71.53

72.69

61.08

75.06

75.06

D7

­44.08

­5.56

­1.16

­4.90

6.5

5.30

­49.63

­45.23

­48.98

­38.77

­50.79

­53.49

­44.30

­49.53

­40.34

­54.53

­45.34

­54.53

­38.77

­54.53

D8

0

­19.54

­3.03

0.84

3.14

­3.11

­22.57

­18.71

­16.41

­22.65

­21.74

­19.45

­25.07

­15.97

­21.59

­18.69

­24.31

­25.07

­15.97

­25.07

D8

­6.56

­2.14

1.06

0.05

0.03

1.1

­8.71

­5.50

­6.51

­6.54

­7.64

­8.44

­8.47

­5.55

­5.58

­7.48

­7.51

­8.71

­5.50

­8.71

D8

2.2

­13.60

­1.26

­0.33

­3.03

3.16

­14.85

­13.93

­16.62

­10.43

­15.18

­17.45

­11.88

­16.62

­11.05

­17.75

­12.18

­17.75

­10.43

­17.75

D9

0

­27.42

­2.62

­1.41

5.32

­5.29

­30.04

­28.83

­22.09

­32.70

­31.46

­24.99

­34.54

­23.90

­33.45

­26.26

­35.81

­35.81

­22.09

­35.81

D9

43.18

2.7

8.07

­1.55

0.45

­0.87

51.25

41.63

43.64

42.32

49.70

50.85

49.66

42.19

41.01

49.46

48.27

41.01

51.25

51.25

D9

­18.58

­2.09

5.4

­1.69

­4.42

3.55

­20.67

­20.27

­23.00

­15.03

­22.36

­24.44

­17.27

­24.08

­16.91

­25.96

­18.79

­25.96

­15.03

­25.96

Trang

39

n

t

P

h

ế

di                                           ệ                                           n

Ti

t

T

NG

H

B

P

C

C

T

L

D

KH UN G

M

Tr

ườ                                           ng                                           h                                           ợ                                           p

t

tr

i

ng

(                                           đơ                                           n                                           v                                           ị                                           KN)

tr

Giá

l

ự                                           c                                           c                                           ắ                                           t                                           c

t

a

các

h                                           ợ                                           p                                           (                                           đơ                                           n

v

ổ                                           h                                           ợ                                           p

T

TT

KN)

GT

HT

HT1 2

GP

TH3

TH

2

TH1

TH4

TH7

TH

6

TH5

TH8

TH11

TH

10

TH9

Q

min

|Q|

ma

x

max

D1

Q

0                                           ­90.96                                           ­23.78                                           ­0.01                                           14.48                                           ­14.65                                           ­114.7                                           ­23.79                                           ­76.48

­105.6                                           ­114.7                                           ­99.33                                           ­125.5                                           ­77.93                                           ­104.2                                           ­99.33                                           ­125.6                                           ­125.55

­76.48                                           125.55

D1

2.09

0.60

3.25

­0.01

14.48

­14.65

2.69

0.59

­12.56

2.68

15.66

­10.56

15.11

16.57

­11.10

15.65

­10.56

­12.56

16.57

16.57

D1

95.14

24.97

­0.01

6.5

14.48

­14.65

120.1

24.96

109.6

120.1

130.7

104.4

108.2

81.95

80.49

130.6

104.4

80.49

130.65

130.65

D2

0

­11.93

­1.55

­5.07

15.39

­15.51

­13.48

­6.62

3.46

­27.44

­18.55

0.53

­27.28

­2.65

­30.45

­4.04

­31.85

­31.85

3.46

31.85

D2

­4.49

­1.55

0.38

1.1

15.39

­15.51

­6.04

­1.17

10.90

­20.00

­5.66

7.97

­19.84

9.70

­18.11

8.30

­19.50

­20.00

10.90

20.00

D2

2.95

­1.55

5.82

15.39

2.2

­15.51

1.41

4.27

18.34

­12.56

7.23

15.41

­12.40

22.04

­5.77

20.65

­7.16

­12.56

22.04

22.04

D3

0

­76.21

­20.41

­0.10

18.46

­18.54

­96.63

­20.51

­57.75

­94.76

­96.73

­77.97

­111.3

­59.69

­92.99

­78.06

­111.4

­111.36

­57.75

111.36

D3

­0.82

­0.16

­0.10

18.46

­18.54

2.7

­0.99

­0.26

17.64

­19.37

­1.09

15.64

­17.66

15.70

­17.60

15.55

­17.75

­19.37

17.64

19.37

D3

5.4

74.56

20.09

­0.10

18.46

­18.54

94.65

19.99

93.02

56.02

94.55

109.3

75.95

91.09

57.78

109.2

75.86

56.02

109.25

109.25

D4

0

­91.42

­0.14

­23.74

6.86

­6.97

­91.56

­23.88

­84.56

­98.39

­115.3

­85.37

­97.81

­106.6

­119.1

­106.7

­119.2

­119.18

­84.56

119.18

D4

1.63

3.25

­0.14

0.64

6.86

­6.97

1.49

0.50

8.49

­5.34

2.12

7.68

­4.77

8.38

­4.07

8.25

­4.20

­5.34

8.49

8.49

D4

94.68

­0.14

6.5

25.01

6.86

­6.97

94.54

24.87

101.5

87.71

119.6

100.8

88.28

123.4

110.9

123.2

110.8

87.71

123.36

123.36

D5

0

­10.60

­4.78

­1.63

7.35

­7.46

­15.38

­6.41

­3.25

­18.06

­17.00

­8.29

­21.62

­5.45

­18.78

­9.75

­23.08

­23.08

­3.25

23.08

D5

­3.16

0.66

1.1

7.35

­7.46

­2.49

­0.96

4.19

­1.63

­10.62

­4.12

4.05

­9.28

1.99

2.59

­10.74

­11.34

4.19

­11.34

11.34

D5

4.29

6.11

­1.63

2.2

7.35

­7.46

10.40

4.48

11.63

­3.18

8.77

16.40

3.07

9.43

­3.89

14.93

1.60

­3.89

16.40

16.40

D6

0

­76.04

­0.04

­20.43

8.74

­8.88

­76.08

­20.47

­67.30

­84.92

­96.51

­68.21

­84.07

­86.56

­102.4

­86.59

­102.5

­102.46

­67.30

102.46

D6

­0.66

­0.04

­0.18

8.74

2.7

­8.88

­0.69

­0.22

8.09

­9.54

7.18

­8.68

7.05

­8.81

7.02

­0.87

­8.84

­9.54

8.09

9.54

D6

74.73

­0.04

20.07

8.74

­8.88

5.4

74.69

20.03

83.47

65.85

94.76

66.70

100.7

84.80

100.6

84.77

82.56

65.85

100.66

100.66

D7

0

­59.34

­9.57

­0.19

1.25

­1.50

­68.91

­9.76

­58.09

­60.84

­69.10

­66.83

­69.30

­58.39

­60.86

­67.00

­69.47

­69.47

­58.09

69.47

D7

3.25

2.28

0.33

­0.19

1.25

­1.50

0.14

3.52

0.78

2.42

3.69

2.61

1.22

3.23

0.76

3.53

1.05

3.69

0.76

3.69

D7

63.89

6.5

10.24

­0.19

1.25

­1.50

74.12

65.13

62.39

73.94

74.22

71.75

10.05

64.84

62.37

74.05

71.58

62.37

74.22

74.22

D8

0

­20.90

­0.81

­0.95

2.80

­2.85

­21.70

­1.75

­18.10

­23.75

­22.65

­19.10

­24.19

­19.23

­24.31

­19.95

­25.04

­25.04

­18.10

25.04

D8

­2.70

1.1

0.53

2.80

­2.85

­3.51

­0.28

­0.81

0.10

­5.55

­2.98

­0.91

­5.99

­4.79

­0.43

­5.52

­5.99

0.30

0.30

5.99

D8

15.49

­0.81

2.2

2.80

­2.85

14.69

1.20

18.29

2.01

12.64

16.69

17.29

12.20

19.82

19.09

14.01

12.20

19.82

14.73

19.82

D9

0

­50.66

­7.82

0.05

1.80

­1.64

­58.48

­7.77

­48.86

­52.30

­58.43

­56.08

­59.17

­48.99

­52.09

­56.03

­59.13

­59.17

­48.86

59.17

D9

­1.64

­0.10

0.05

2.7

1.80

­1.64

­1.74

­0.05

0.17

­3.27

­1.68

­0.10

­3.20

0.03

­3.06

­0.06

­3.15

­3.27

0.17

3.27

D9

47.39

7.63

0.05

1.80

5.4

­1.64

55.01

7.68

49.19

45.75

55.06

55.87

52.78

49.06

45.96

55.92

52.82

45.75

55.92

55.92

Trang

40

ử Ph

n

t

t

Ti

di                                           ệ                                           n

ế

H

B

T

P

NG

C

N

L

C

Ự Ộ

I

T

đơ

KHUNG

n

Moment                                            (

v ị                                           KN.m)                                           L                                           ự

(

đơ

n

c                                            d                                            ọ                                            c

v                                           ị                                           KN)                                           T

c

ơ

b                                           ả                                           n                                           tính                                           toán

ổ                                            h                                            ợ                                            p

HT

1

HT2

TT

GT

GP

HT2

TT HT

1

GT max

M N

GP

t

ư N

min

t

ư

M

N

ư

M

max

t

C1                                           0                                           ­12.83                                           ­3.79                                           0.43                                           49.04                                           ­47.92                                           ­437.34

­47.16                                           ­35.76                                           22.59                                           ­23.12                                           36.21                                           ­414.75                                           ­60.75                                           ­460.46

­58.98                                           ­532.77

C1

4.8

26.34

7.81

­0.92

­30.44

32.16

­428.10

­47.16

­35.76

22.59

­23.12

62.31

­491.35

­4.10

­405.51

61.49

­523.53

C2

0

11.60

3.49

­0.63

45.88

­46.20

­519.66

­67.87

­57.43

2.95

­2.71

57.48

­516.71

­34.60

­522.37

14.46

­644.96

C2

4.8

­22.97

­6.92

1.25

­41.32

41.62

­510.42

­67.87

­57.43

2.95

­2.71

18.65

­513.13

­66.39

­568.85

­28.64

­635.72

C3

0

­6.87

­2.18

0.48

46.33

­46.64

­448.17

­57.71

­51.65

3.47

­3.24

39.46

­444.70

­53.52

­451.41

­8.57

­557.53

C3

4.8

14.40

4.55

­1.00

­42.24

42.51

­438.93

­57.71

­51.65

3.47

­3.24

56.90

­442.17

­27.85

­435.46

17.95

­548.29

C4

0

8.74

2.67

­0.31

48.32

­50.03

­392.31

­41.34

­31.85

­29.01

29.06

57.06

­421.31

­41.29

­363.25

54.35

­484.29

C4

4.8

­17.13

­5.25

0.63

­33.34

32.09

­383.07

­41.34

­31.85

­29.01

29.06

14.95

­354.01

­51.86

­446.38

­51.30

­475.05

C5

0

­32.01

­5.97

­2.54

19.74

­18.73

­263.66

­13.66

­35.75

8.11

­8.47

­12.27

­255.55

­56.53

­315.75

­56.53

­315.75

C5

3.6

31.47

1.98

6.54

­13.79

15.05

­257.72

­13.66

­35.75

8.11

­8.47

52.69

­309.81

17.68

­249.61

52.69

­309.81

C6

0

28.32

5.05

2.02

19.86

­20.10

­317.47

­31.64

­40.36

2.04

­1.85

52.56

­380.43

8.22

­319.31

35.40

­389.47

C6

3.6

­27.84

­1.46

­5.59

­21.88

22.10

­311.53

­31.64

­40.36

2.04

­1.85

­5.74

­313.37

­53.87

­374.49

­34.88

­383.53

C7

0

­17.45

­3.27

­1.08

20.76

­20.98

­273.89

­29.12

­33.73

0.40

­0.20

3.31

­273.49

­40.25

­330.63

­21.81

­336.73

C7

3.6

17.00

0.68

3.61

­22.51

22.76

­267.95

­29.12

­33.73

0.40

­0.20

41.35

­324.69

­5.51

­267.55

21.30

­330.79

C8

0

21.04

3.98

1.80

19.95

­21.33

­235.02

­11.54

­31.95

­10.55

10.52

44.19

­283.65

­0.29

­224.50

44.19

­283.65

C8

3.6

­20.73

­1.43

­4.37

­15.89

15.01

­229.08

­11.54

­31.95

­10.55

10.52

­5.72

­218.56

­40.25

­277.71

­40.25

­277.71

C9

0

­30.14

­0.74

­6.48

10.17

­9.22

­92.82

­13.52

­2.29

1.25

­1.50

­19.97

­91.57

­44.94

­108.40

­37.36

­108.63

C9

3.6

29.29

3.40

2.38

­3.19

4.45

­86.88

­13.52

­2.29

1.25

­1.50

38.49

­102.46

26.10

­85.63

35.06

­102.69

C10

0

25.93

0.18

5.57

6.95

­7.25

­120.37

­14.99

­4.01

1.56

­1.35

37.36

­136.07

18.68

­121.72

31.68

­139.37

C10

3.6

­24.53

­2.53

­1.99

­8.04

8.41

­114.43

­14.99

­4.01

1.56

­1.35

­16.12

­115.78

­35.84

­130.13

­29.05

­133.43

C11

0

­15.26

0.23

­3.62

7.32

­7.47

­101.74

­10.97

­5.21

­1.00

1.22

­7.94

­102.73

­25.24

­105.33

­18.65

­117.91

C11

3.6

13.82

1.37

1.08

­8.35

8.45

­95.80

­10.97

­5.21

­1.00

1.22

23.63

­109.26

5.47

­96.79

16.27

­111.97

C12

0

19.46

0.48

4.31

9.47

­10.79

­80.87

­11.58

­2.16

­1.80

1.64

32.29

­94.85

8.67

­79.23

32.29

­94.85

C12

3.6

­18.58

­2.09

­1.69

­4.42

3.55

­74.93

­11.58

­2.16

­1.80

1.64

­15.03

­73.29

­25.96

­88.91

­25.96

­88.91

Trang                                           41

6.

Tính

toán

c                                           ố

t

thép

6.1.

Tính

toán

c

t

thép

cho

d

Đố

m

i

v                                           ớ

i

d                                           ầ

m

tính

toán

t                                           ạ

i

3

ti                                           ế

t

di                                           ệ

n

(hai

g                                           ố

i

gi                                           ữ

a

nh                                           ị

p),

ch                                           ọ

n

mômen

l                                           ớ

n

nh                                           ấ

t                                           ở

nh                                           ị

M

p

g

i

max

M

,

|Q|

min

để

max

tính

toán

c

t

thép.

Đố

i

v                                           ớ

i

d                                           ầ

m,

sàn                                           đổ

toàn

kh                                           ố

i,

khi

tác

d                                           ụ

ng

c                                           ủ

a

mômen

gây

nén

cho

b                                           ả

n

cánh

thì

ta

k

đế

n

nh

h

ưở

ng

c

a

b

n

cánh

trong

tính

toán

khi

b

n

cánh

ch

u

kéo

thì

b

qua

nh

h

ưở

ng

b

n

cánh.

a.

Tính

c

t

thép

d

c

V

i

c

p

độ

b

n

bêtông

B20

(t

ươ

ng

đươ

ng

M250)

c

t

thép

CII

tra

b

ng:

a

=

0,429,

R

ξ

=

0,623

.

R

­

V                                           ớ

i

ti                                           ế

t

di                                           ệ

n

cánh

n                                           ằ

m

trong

vùng

kéo                           (cid:222)

Tính

theo

ti                                           ế

t

di                                           ệ

n

ch                                           ữ

nh                                           ậ

t

+

Gi

(b×h):

thi

ế

t

a

=(3÷6)

cm

(cid:222)

h

=

0

h

-

a

α

+

Tính

=

α

m

:

m

.

M

b

.

R

h

b

N

ế

u

α

0

m

>

a

T

ă

ng

kích

R                           (cid:222)

th

ướ

c

ti

ế

t

di

n

(t

ă

ng

chi

u

cao

h).

N

ế

u

α

m

£

a

(cid:222)

Tra

b

R

ng

ho

c

tính

z

=

0

,

5

.(

1

+

1

-

2

.

a

)

m

+

s

Tính

A

=

:

s

A

.

M

h

R

.

0

s

z

ng

+

m

hàm

Ki

= ể

l

m

ượ

tra

A

.

s

b

h

0

i

đả

.100%

m

ph

b

m

o

m

min

v

=

min

i

m

0.1%

­                                           V                                           ớ                                           i                                           ti

ế                                           t                                           di                                           ệ                                           n                                           có                                           cánh                                           n                                           ằ

m                                           trong                                           vùng                                           nén                                           tính                                           toán

theo                                           ti                                           ế                                           t                                           di                                           ệ                                           n                                           ch                                           ữ

T:

+

Xác

đị

nh

v

trí

tr

c

trung

hoà:

M

=

R

f

.b

b

.h

’f

.(h

’f

o

0,5.h

)

Tr

ườ

ng

h

’f

p

M

£

M

:

f

Tr

c

trung

hoà

qua

cánh

Tr

ườ

ng

h

p

M

>M

:

Tr

c

f

trung

hoà

qua

s

ườ

n

Tr                                           ườ

ng

h                                           ợ

p

tr                                           ụ

c

trung

hoà

qua

cánh:

b

f

C

S

b

S

C

+

-

S C S C

b

f

b

'

'

V

i

S

độ

c

v

ươ

ng

c

a

cánh

l

y

giá

tr

nh

nh

t

trong

các

giá

tr

sau:

+

1

'

+

1/2

kho

ng

cách

thông

th

y

gi

a

các

d

m

d

c

Trang

42

hoà

c             trung   qua              s                                                           ườ

:

b

n

Tr                                           ườ

h

f

ng                                             ợ

tr

p                                                         ụ

S

S

C

b

-

C

C

+

S

S

C

b

Tính

(cid:222)

theo

ti

ch

ế

t

T

+

di

Gi

n

thi

ế

t

h

a

(cid:222)

=(3÷6)cm

0

=

h

b

f

-

a

=

+

Tính

α

m                                           :

α

m

R

b

M

.(

b

-

f

'

-

f

b

).

.(

h

h

'

f

-

0,5.

)

h

0

R

.

b

h

.

b

0

N

ế

u

α

α

m                                           >

T

ă

ng

kích

th

ướ

R                           (cid:222)

c

ti

ế

t

di

n

(t

ă

ng

chi

u

cao

h).

N

ế

u

α

£

m

α

(cid:222)

Tra

b

ng

R

ho

c

tính

x

=

1

-

1

-

2

.

a

+

m

Tính

A

R

b

:

R

s

s

l

+

tra ượ

ng

Ki

hàm

m

m

s

b

.

=

h

A

0

.100%

ph

i

o

b

đả

m

m

i

m

v

m

min

0.1%

min

­

=

V                                           ớ                                           i                                           tr                                           ườ                                           ng                                           h                                           ợ                                           p                                           ti

ế                                           t                                           di                                           ệ                                           n                                           ch                                           ỉ                                           có

cánh                                           ở                                           1                                           bên:

b

b b

(cid:222)

Tính                                           nh                                           ư                                           ti                                           ế

t                                           di                                           ệ                                           n                                           ch                                           ữ                                           nh                                           ậ

h                                           (b                                           ỏ

t                                           b                           ·

qua                                           s                                           ự                                           làm                                           vi                                           ệ                                           t

c                                           ủ                                           a                                           cánh)

­

Khi

chi

u

cao

c

a

d

m

h

d

650

mm

thì

ta

đặ

t

thêm

c

t

thép

ph

vào

m

t

bên

c

a

ti

ế

t

di                                           ệ

n

d                                           ầ

m.

Các

c

t

thép

này

ch                                           ị

u

các                                           ứ

ng

su                                           ấ

t

do

co

ngót

nhi                                           ệ

t

độ

gi                                           ữ

cho

khung

c                                           ố

t

thép

không

b

l

ch

khi

thi

công.

C                                           ố                                           t                                           thép                                           d                                           ọ                                           c

trong                                           d                                           ầ                                           m                                           đượ                                           c                                           tính                                           toán

d                                           ự                                           a                                           trên                                           c                                           ơ                                           s                                           ở

lý                                           thuy                                           ế                                           t                                           trên                                           và                                           đượ                                           c

l                                           ậ                                           p

thành

b

ng

tính

sau:

Trang

43

Trang                                           44

D6

D

5

D8

D 7

D 9

Trên

GT

20

ướ

­31.49 D

i

0.00

4

26

80

c.t

0.00

o

0.52

2Ø16

0.10%

4.02

Trên

0.77%

­15.06

20

N

i

D

0.00

ướ

80

26

0.00

c.t

4

0.52

0.10%

o

2Ø16

0.77%

GP

Trên

4.02

20

D

ướ

­22.32

i

80

4

0.00

26

c.t

o

0.00

0.52

2Ø16

4.02

0.10%

Trên

0.77%

­74.25

GT

ướ

i

20

0.00

D

51

0.00

120

4

c.t

1.02

0.10%

o

4.02

0.39%

2Ø16

N

0.00

Trên

D

ướ

20

120

4

i

77.98

0.02

51

0.99

5.52

3Ø16

0.54% 6.03

Trên

0.59%

­72.55

20

GP

i

D

0.00

ướ

120

51

0.00

c.t

4

1.02

0.10%

o

2Ø16

0.39%

GT

4.02

Trên

D

20

ướ

i

­38.49

120

4

0.00

c.t

o

51

0.00

1.02

2Ø16

4.02

0.10%

Trên

0.00

0.39%

N

i

ướ

75.06

20

D

51

0.02

120

4

0.99

0.52%

3Ø16

5.31

0.59%

GP

Trên

6.03

20

D

ướ

­54.53

i

120

0.00

4

51

c.t

0.00

o

1.02

2Ø16

0.10% 4.02

0.39%

Trên

GT

­25.07

20

i

D 0.00

ướ

80

26

0.00

4

c.t

0.52

0.10%

o

0.77%

2Ø16

N

4.02

20

Trên

D

ướ

­8.71

i

80

4

0.00

c.t

o

26

0.00

0.52

2Ø16

4.02

0.10%

Trên

­17.75

0.77%

GP

i

ướ

0.00

20

D

26

0.00

80

4

c.t

0.52

0.10%

o

4.02

0.77%

2Ø16

GT

­35.81

Trên

D

20

ướ

0.00

i

120

4

0.00

51

c.t

o

0.10%

2Ø16

1.02

4.02

Trên

N

0.00

0.39%

D

ướ

i

51.25

20

4

51

120

0.01

3.62

0.35%

0.99

0.39%

2Ø16

GP

4.02

20

Trên

D

ướ

­25.96

i

120

4

0.00

c.t

o

51

0.00

1.02

2Ø16

4.02

0.10%

Trang

0.39%

45

b.                                           Tính                                           toán                                           c                                           ố                                           t

thép                                           đ                                           ai

Ki                                           ể

m

tra

đ

i                                           ề

u

ki                                           ệ

n

kh                                           ả

n

ă

ng

ch                                           ị

u

c                                           ắ

t

c                                           ủ

a

Q

bêtông:

b

=

j

min

b

.

3

(

1

+

j

f

+

j

)

R

n

bt

.

b

.

h

+

o

N

ế

u

Q

>

bmin

Q

không

c

n

tính

toán

c

t

thép

đ

ai,

ch

đặ

t

c

t

ngang

theo

c

u

t

o.

+

N

ế

u

Q

bmin

Q

c

n

tính

toán

c

t

thép

đ

ai

Đố

i

v

i

bêtông

n

ng

l

y

j

b

=

0,

6

,

3

tính

toán

v

i

ti

ế

t

di

n

ch

nh

t

b

qua

nhh

ưở

ng

c

a

cánh

l

y

j

=

0

,

f

b

qua

nh

h

ưở

ng

l

c

d

c

l

y

j

=

0

n

.

Tính

toán

c

t

đ

ai

khi

không

đặ

t

c

t

xiên

­

Ch

n

đ

f

ai

,

n

nhánh.

­

Kho

ng

cách

gi

a

hai

c

t

đ

ai

theo

tính

s

tt

toán:

R

=

.

sw

A

2

.(1

.4

+

j

j

sw

b

n

).

+

R

j

f

bt

.

b

0

.

2

h

Q

Đố

i

v

i

bêtông

n

ng

l

y

j

b                                           2

=

2

­

Kho

ng

cách

l

n

nh

t

gi

a

hai

c

t

đ

ai

là:

j

s

ma x

b

=

4

.(1

).

+

R

j

.

bt

f

b

.

0

h

Q

Đố

i

v

i

bêtông

n

ng

l

y

j

b

4                           =

1,

5

­

Kho

ng

cách

c

t

đ

ai

l

y

theo

yêu

c

u

c

u

t

o

nh

ư

sau:

Đ

o

n

d

m

g

n

g

i

l

y

b

ng

1/4

nh

p

khi

d

m

ch

u

t

i

tr

ng

phân

b

đề

u,

l

y

b

ng

kho

ng

cách

t

g

i

đế

n

l

c

t

p

trung

d

m

đầ

u

tiên

(nh

ư

ng

không

h

ơ

n

1/4

nh

p)

khi

d

m

ch

u

l

c

t

p

trung

h

2

h

3

v

Khu

+ ự

gi

c

£

a

ct

min(

d

m:

s

mm

)

30

3                                           h

0

;

4

­                                           Kho                                           ả                                           ng                                           cách                                           đ                                           ai                                           thi

ế                                           t                                           k                                           ế                                           :

min(

s

s

tk

tt

£

;

s

s

max

ct

)

;

­                                           Ki                                           ể                                           m                                           tra                                           kh                                           ả

n                                           ă                                           ng                                           ch                                           ị                                           u                                           ứ                                           ng                                           su                                           ấ

t                                           nén                                           chính                                           trên                                           b                                           ụ                                           ng

d                                           ầ                                           m:

Q

£

0

,

3

.

j

b

.

j

1

w

1

.

R

.

b

.

h

b

o

H

s

:

j

b

=

1

-

1

b

.

R

H

b

s

xét

đế

n

nh

h

ưở

ng

c

a

c

t

đ

ai:

j

w

=

1

1

+

5

a

.

m

<

1

,

3

w

ó:

=

Trong

a

đ

b

E

s

b

E

.

A

(cid:222)

Đ                                           i                                           ề                                           u                                           ki

s

ệ                                           n                                           đượ                                           c                                           th                                           ỏ                                           a                                           mãn                                           hay

không.

Tr an g

B

46

Ả                                           NG                                           TÍNH                                           THÉP                                           Đ                                           AI                                           D                                           Ầ

M                                           KHUNG

Ph

n

t                                           ử

Ti

| Q|                                            max

di

ế

b

n

t

h

Lo                                           ạ                                           i                                           t.d

ct

o

a

s                                            tk

F

s                                           tt                                           s                                           max                                           s

h

nhánh

(mm)

(cm)                                           (cm)                                           (mm)                                           (cm)                                           (cm)                                           (cm)

(g                                      (daN )                                    ố                                        i­nh                                      (cm)                                    ị                                        p)                                      (cm)

thép

D1                                           0                                           G                                           12,555

Ch ọ                                           n

20                                           55                                           4.0                                           51                                           T.T                                           2                                           6                                           41.8

55.9                                           18.3                                           180                           F                 6                                           150

D1

3.25

N

1,657

20

55

4.0

51

C.T

2

6

2401.6

C.T

41.3

410

F

6

200

D1

6.5

G

13,065

20

55

4.0

51

T.T

2

6

38.6

53.8

18.3

180

F

6

D2                                           0

150

G                                           3,185                                           20                                           30                                           4.0                                           26                                           T.T                                           2

6                                           169.0                                           57.3                                           15.0                                           150                           F                 6                                           150

D2

1.1

N

2,000

20

30

4.0

26

C.T

2

6

428.3

C.T

15.0

150

F

6

150

D2

2.2

G

2,204

20

30

4.0

26

C.T

2

6

352.8

C.T

15.0

150

F

6

150

D3                                           0                                           G                                           11,136                                           20                                           55                                           4.0

51                                           T.T                                           2                                           6                                           53.2                                           63.1                                           18.3                                           180

F                 6                                           150

D3

2.7

N

1,937

20

55

4.0

51

C.T

2

6

1757.8

C.T

41.3

410

F

6

200

D3

5.4

G

10,925

20

55

4.0

51

T.T

2

6

55.2

64.3

18.3

180

F

6

D4                                           0                                           G                                           11,918

150

20                                           55                                           4.0                                           51                                           T.T                                           2                                           6                                           46.4

58.9                                           18.3                                           180                           F                 6                                           150

D4

3.25

N

849

20

55

4.0

51

C.T

2

6

9147.9

C.T

41.3

410

F

6

200

D4

6.5

G

12,336

20

55

4.0

51

T.T

2

6

43.3

56.9

18.3

180

F

6

D5                                           0

150

G                                           2,308                                           20                                           30                                           4.0                                           26                                           C.T                                           2

6                                           321.7                                           C.T                                           15.0                                           150                           F                 6                                           150

D5

1.1

N

1,134

20

30

4.0

26

C.T

2

6

1333.6

C.T

15.0

150

F

6

150

D5

2.2

G

1,640

20

30

4.0

26

C.T

2

6

637.5

C.T

15.0

150

F

6

150

D6                                           0                                           G                                           10,246                                           20                                           55                                           4.0

51                                           T.T                                           2                                           6                                           62.8                                           68.5                                           18.3                                           180

F                 6                                           150

D6

2.7

N

954

20

55

4.0

51

C.T

2

6

7251.1

C.T

41.3

410

F

6

200

D6

5.4

G

10,066

20

55

4.0

51

T.T

2

6

65.1

69.8

18.3

180

F

6

D7                                           0                                           G                                           6,947

150

20                                           55                                           4.0                                           51                                           T.T                                           2                                           6                                           136.6

101.1                                           18.3                                           180                           F                 6                                           150

D7

3.25

N

369

20

55

4.0

51

C.T

2

6

48314.2

C.T

41.3

410

F

6

200

D7

6.5

G

7,422

20

55

4.0

51

T.T

2

6

119.7

94.6

18.3

180

F

6

D8                                           0

150

G                                           2,504                                           20                                           30                                           4.0                                           26                                           C.T                                           2

6                                           273.4                                           C.T                                           15.0                                           150                           F                 6                                           150

D8

1.1

N

599

20

30

4.0

26

C.T

2

6

4770.9

C.T

15.0

150

F

6

150

D8

2.2

G

1,982

20

30

4.0

26

C.T

2

6

436.4

C.T

15.0

150

F

6

150

D9                                           0                                           G                                           5,917                                           20                                           55                                           4.0

51                                           T.T                                           2                                           6                                           188.3                                           118.7                                           18.3                                           180

F                 6                                           150

D9

2.7

N

327

20

55

4.0

51

C.T

2

6

61552.7

C.T

41.3

410

F

6

200

D9

5.4

G

5,592

20

55

4.0

51

T.T

2

6

210.9

125.6

18.3

180

F

6

Trang                                           47

150

6.2.Tính                                           toán                                           c                                           ố                                           t                                           thép

cho                                           c                                           ộ                                           t

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t

tính

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c                                           ấ

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nén

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l                                           ự                                           c                                           d                                           ọ

:                                           momen                                           và

tr                                           ọ                                           ng                                           dài

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gây                                           ra.

h                                           ạ                                           n

Tr an g

48

M                                           ,                                           N                                           :                                           n

ộ                                           i                                           l                                           ự                                           c                                           tính                                           toán                                           ti

ế                                           t                                           di                                           ệ                                           n                                           (l                                           ấ                                           y                                           giá

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16

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C

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Trang                                           51

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26.67

12.07

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Trang

3.02

52

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C

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38.5

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3.6

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Trang

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53

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t

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ế

t

di

T

h

n

p

c

ơ

b

n

tính

toán

M                                           max                                           N                                           t                                           ư                                           M

min                                           N                                           t                                           ư                                           M                                           t                                           ư                                           N                                           max

C9                                           0.00

­19.97                                           ­91.57                                           ­44.94                                           ­108.40                                           ­37.36                                           ­108.63

C9                                           3.60                                           38.49                                           ­102.46                                           26.10                                           ­85.63

35.06                                           ­102.69

C12                                           0.00                                           32.29                                           ­94.85

8.67                                           ­79.23                                           32.29                                           ­94.85

C12                                           3.60

­15.03                                           ­73.29                                           ­25.96                                           ­88.91                                           ­25.96                                           ­88.91

n

t

ử Ph

ế                                           t

n Ti

di                                           ệ

N

e                                           o

(cm)

M

Chi                                           ề                                           u

(cm)

h

dài

(kN.m)                                           (kN)

e

/h

­19.97                                           ­91.57

0

21.81                                           0.73

C

­44.94                                           ­108.40

1.38

41.45

3.60

C9

34.39

38.49                                           ­102.46                                           37.56                                           1.25

­37.36                                           ­108.63 1.15                                                30

Đ

26.10                                           ­85.63                                           30.48

1.02

34.14                                           1.14

32.29

35.06                                           ­102.69

­94.85

34.05                                           1.13

C

8.67                                           ­79.23

0.36

10.94

3.60

C12

34.05

­15.03                                           ­73.29                                           20.51                                           0.68

32.29                                           ­94.85 1.13                                                30

Đ

­25.96                                           ­88.91                                           29.20

­25.96                                           ­88.91                                           29.20                                           0.97

0.97

­

T

b

ng

t

h

p

ch

n

c

p

n

i

l

c

M,

N

c

a

ph

n

t

c

t

C9

độ

l

ch

tâm

e

o                                           l

n

nh

t

e

=

1.38

o

>

0.5

nên

ta

c

u

t

o

c

t

thép

nút

góc

trên

cùng

theo

tr

ườ

ng

h

p

e

/h>0.5

=80 2Ø16

r

o

13

r

=80

2Ø16

13

l

s

Ø6 15 a100

2Ø16 =

25 0

2

=

2Ø16

Ø6

l

6

250 15 a100

300

s

B

300

E

Tr an g

54

­

T

b

ng

t

h

p

ch

n

c

p

n

i

l

c

M,

N

c

a

ph

n

t

c

t

C12

độ

l

ch

tâm

e

o                                           l

n

nh

t

e

=

1.13>

0.5

nên

o

ta

c

u

t

o

c

t

thép

nút

góc

trên

cùng

theo

tr

ườ

ng

h

p

e

/h

>0.5

o

­

t

s

e

/h

l

n

nên

o

yêu

c

u

neo

c

t

thép

ch

u

kéo

trên

d

m

vào

c

t

càng

sâu.

Tùy

thu

c

vào

s                                           ố

l                                           ượ

ng

thanh

thép

ch                                           ị

u

kéo

c                                           ắ

t

c                                           ố

t

thép

ch                                           ị

u

kéo                                           ở

m                                           ộ

t

ho                                           ặ

c

hai

ti                                           ế

t

di                                           ệ

n.                                           Ở

đ

ây

c

t

thép

ch

u

kéo

trên

d

m

ch

f

2

16

nên

ch

c

n

c

t

t

i

m

t

ti

ế

t

di

n,

chi

u

dài

đ

o

c

t

cách

mép

n

d

ướ

i

c

a

d

m

m

t

đ

o

n

l

đượ

c

an

xác

đị

nh

theo

công

th

c:

(cid:230)

R

Ł

ł

s

R

b

(cid:246)

bêtông

ch

u

kéo

ta

tính

đượ

c

chi

u

dài

đ

o

n

neo

là:

(cid:230)

R

(cid:230)

(cid:246)

b

2800

Ł

Ł

ł

R

115

ł

(cid:246)

­

C

t

thép

d

ướ

i

phía

d

ướ

i

c

a

d

m

đượ

c

neo

quá

mép

c

t

m

t

đ

o

n

l

s                                           ≥

15

f

.

V

i

thép

f

16

thì

tính

đượ

c

l

15

f

s

=

15×16=240

mm

.

(cid:222)

Ch

n

l

=

250

s

mm

­

Tr                                           ườ

ng

h                                           ợ

p

t                                           ạ

i

ti                                           ế

t

di                                           ệ

n

mép

c                                           ộ

t

xu

t

hi                                           ệ

n

mômen

d

ươ

ng

thì

c                                           ố

t

thép

phía

d                                           ướ

i

c                                           ủ

a

d

m

ph

i

đượ

c

neo

vào

v

i

đ

o

n

l

=

l

s

.

an

­                                           Để

tránh

t

p

trung                                           ứ

ng

su                                           ấ

t,

c                                           ố

t

thép

d                                           ầ

m

neo

xu                                           ố

ng

c                                           ộ

t

ph                                           ả

i                                           đượ

c

u                                           ố

n

cong

v                                           ớ

i

bán

kính

r

f

5

=

5×16=80(

mm

)

cho

tr

ườ

ng

h

p

không

c

u

t

o

nách.

7.

B

trí

c

t

thép.

Xem

b                                           ả

n

v                                           ẽ

b                                           ố

trí

c                                           ố

t

thép

Trang                                           55

khung.

TÀI                                           LI                                           Ệ                                           U                                           THAM

KH                                           Ả                                           O

1.

TCVN

5574

­

2012.

K

ế

t

c

u

bêtông

c

t

thép

­

Tiêu

chu

n

thi

ế

t

k

ế

.

2.

TCVN

2737

­

1995.

T

i

tr

ng

tác

độ

ng

­

Tiêu

chu

n

thi

ế

t

k

ế

.

3.

Hu

ế

,

Phan

Minh

Tu

n

Khung

bêtông

c

t

thép

toàn

kh

i.

Nhà

xu

t

b

n

khoa

h

c

k

thu

t,

N

i,

2009

4.

Phan

Quang

Minh,

Ngô

Th

ế

Phong,

Nguy

n

Đ

ình

C

ng

K

ế

t

c

u

tông

c

t

thép

(

Ph

n

c

u

ki

n

c

ơ

b

n)

Nhà

xu

t

b

n

khoa

h

c

k

thu

t,

N

i,

2006

5.

Ngô

Th

ế

Phong,

Tr

n

C

ườ

ng,

Tr

nh

Kim

Đạ

m,

Nguy

n

Ninh

K

ế

t

c

u

tông

c

t

thép

(

Ph

n

c

u

ki

n

nhà

c

a)

Nhà

xu

t

b

n

khoa

h

c

k

thu

t,

N

i,

2001

6.

V

ũ

M

nh

Hùng

S

tay

th

c

hành

thi

ế

t

k

ế

k

ế

t

c

u

công

trình

Nhà

xu

t

b

n

xây

d

ng,

N

i,

2010

Tr an g

56

M

C

L

C

TÍNH

TOÁN

THI                                           Ế

T

K                                           Ế

K

T

C                                           Ấ

U

KHUNG

NGANG

.............................................

1

1.

Gi

i

thi

u

t

k

ế

t

c

u:

.......................................................................................

3

2.Ch

n

v

t

li

u

s

ơ

b

ch

n

kích

th

ướ

c

ti

ế

t

di

n

các

c

u

ki

n

..............................

3

2.1.

Ch

n

v

t

li

u

..................................................................................................

3

a.

Bêtông

............................................................................................................

3

b.

C

t

thép

.........................................................................................................

4

2.2.

Ch

n

s

ơ

b

kích

th

ướ

c

ti

ế

t

di

n

.....................................................................

4

a.

Ch

n

chi

u

dày

c

a

sàn.

................................................................................

4

b.

Ch

n

kích

th

ướ

c

ti

ế

t

di

n

c

a

d

m

...............................................................

4

b.1.

D

m

khung

tr

c

8

...................................................................................

5

b.2.

D

m

d

c

.................................................................................................

5

c.

Ch

n

s

ơ

b

ti

ế

t

di

n

c

t

.................................................................................

5

3.L

p

s

ơ

đồ

tính

khung

ngang

...................................................................................

7

4.

Xác

đị

nh

các

lo

i

t

i

tr

ng

tác

d

ng

lên

khung

.....................................................

8

4.1.

T

ĩ

nh

t

i

...........................................................................................................

8

a.

T

i

tr

ng

trên

2

1m

sàn

...................................................................................

8

b.

T

i

tr

ng

trên

1m

2

t

ườ

ng

...............................................................................

9

c.

Xác

đị

nh

t

ĩ

nh

t

i

tác

d

ng

vào

khung

............................................................

9

c.1.T

ĩ

nh

t

i

t

ng

2,

3

....................................................................................

10

c.2.

T

ĩ

nh

t

i

t

ng

mái

...................................................................................

12

4.2.

Xác

đị

nh

ho

t

t

i

đứ

ng

tác

d

ng

vào

khung

................................................

15

a.

Ho

t

t

i

đơ

n

v

.............................................................................................

15

b.

Tính

tr

ườ

ng

h

p

ho

t

t

i

1

..........................................................................

16

c.

Tính

tr

ườ

ng

h

p

ho

t

t

i

2

...........................................................................

19

4.3.

Xác

đị

nh

ho

t

t

i

gió

tác

d

ng

vào

khung

....................................................

23

5.

Xác

đị

nh

n

i

l

c

t

h

p

n

i

l

c

......................................................................

25

5.1.

Xác

đị

nh

n

i

l

c

...........................................................................................

25

5.2.T

h

p

n

i

l

c

...............................................................................................

38

Trang

57

6.                                           Tính                                           toán                                           c

42

ố                                           t                                           thép                                           ................................................................................................

6.1.

Tính

toán

c

t

thép

cho

d

m

..........................................................................

42

a.

Tính

c

t

thép

d

c

.........................................................................................

42

b.

Tính

toán

c

t

thép

đ

ai

..................................................................................

46

6.2.Tính

toán

c

t

thép

cho

c

t

.............................................................................

48

a.

Chu

n

b

s

li

u

tính

toán:

...........................................................................

48

b.

Tính

toán

c

t

thép

đố

i

x

ng

........................................................................

49

c.

Tính

toán

c

t

thép

đ

ai

cho

c

t.

....................................................................

50

6.3.

Tính

toán

c

u

t

o

các

nút

khung

(tham

kh

o)

..............................................

54

a.Tính

toán

c

u

t

o

nút

góc

trên

cùng

.............................................................

54

7.

B

trí

c

t

thép.

.....................................................................................................

55

TÀI

LI

U

THAM

KH

O

.......................................................................................

56

Tr an g

58