Bài tp tham kho môn Nn móng Trang1
Ging Viên: Trn Vang
TÓM TT NI DUNG CÁC DNG BÀI TP CN NM
.
Chương I: TÍNH TOÁN V MÓNG NÔNG
Mun gii ñư"c các bài toán v móng nông, trư(c h)t ta phi d+i các l-c M, N, H v t/i
tr0ng tâm móng, sau ñó tuỳ theo yêu cu ñ bài mà có các d/ng sau:
1. Bài toán I: Ki8m tra cư+ng ñ9 ñ:t nn dư(i ñáy móng (σ
max
≤ R).
a. Xác ñ@nh σ
max
:
A Trư+ng h"p1:
6
b
F
W
ρ
N
M
e==≤=
→ σ
min
≥ 0 → σ
max
=
(
)
→=+=+
22
2
cm
kg
m
T
?.
a.b
6.M
a.b
N
W
M
F
N
A Trư+ng h"p 2:
6
b
F
W
ρ
N
M
e==>=
→ σ
min
< 0 → σ
max
=
( )
(
)
→=
−
22
cm
kg
m
T
?.
.ae
2
b
3.
2.N
Trong ñó: a là c/nh cMa móng vuông góc v(i trNc cu (m)
b là c/nh cMa móng song song v(i trNc cu (m)
b. Xác ñ@nh R cMa ñ:t nn bOng ñ:t dính hoQc ñ:t cát:
R = 1,2.{R
/
.[1 + k
1.
(b A 2)]+ k
2
.γ.(h A 3)}
2
cm
kg
Trong ñó:
!"#$%&"'
#
(
$)&*!"+
γ!!",$!)- γ.
i
ii
Σh
h.Σ.γ
/
0
"$)1!$%&2$ ')"34(".4
$$)1*$ '
5$-5$2$(67$$$!&'
2. Bài toán II: Ki8m tra cư+ng ñ9 l(p ñ:t y)u cách dư(i ñáy móng m9t ño/n z (σ
Z
≤ R
Z
).
a. xác ñ@nh σ
z
: σ
z
= γ
tb
.(h + z) + α.(p A γ
tb
.h) =
(
)
→
22
cm
kg
m
T
?.
/!-
γ
"
! $)8 2$ 2$ ! ",$
9!)%&1)/
0
'
$$)1*$
: $$ ) %& 9
)
α$)&*2$*!
";9$&$6
b
i
Z
m=
<.
b
a
'
9*!",$9.
=
>
b
z
b
h
z
30
0
h
z
?12$
Bài tp tham kho môn Nn móng Trang2
Ging Viên: Trn Vang
"'@7$
A
-
A
.#(BC#D
#
'"
:
ED
'
γ
"
'$
:
0 F
2
cm
kg
/!-
<
#
<
<
γ
"
@7$$!)
G!,$"(&!$
$67'
5$-"
:
."D':0H
H
$
≤
4
$
A
.$D:
0'IJJJ'
'K)8!87$&-
L)1)&-
)0,8.(nenda
t)0,7.(nenda
m
2
b
N.
M
M
M
g
l
=≤=
"'K)8!87$!-
L)1)&-
0,8m
N.f
H
T
T
g
tr
=≤=
M$)&**!"4
N'IJO-K)8!$%)&$'
L)1)&-
1α
ρ
e
0
=≤
/!-
t.c
t.c
0N
M
e=
)&$$9&)$8-
K)8$P//QR'J)1
!& 1( ) )& $G $& 2$
$
×
".#H
×
N(+'5!2$$P
8$9!$2$(&&1
>.SHH/ T
.NH/ R.H/
$,$6PG '>)11-U9!)0
*P9$
γ
#
.#(S/
0
'U9$0(S
! ",$ !& $ $%& 6
γ
.
#(;/
0
(82'U98*
.
5$)8&6)1!->.SHH/ ( R.H/
(
)
Tm660. 800.0,3420N.0,3MM
/
=+=+=
'L)1)&-
V7$
δ
@
-
0,75.(m)
6
4,5
6
b
ρ
0,825.(m)
800
660
N
M
e
'
===
===
→
P3
ρ
O&
δ
WH'
→
XY*$'
R
>
T
H(0
N(+
0(S
Z
Bài tp tham kho môn Nn móng Trang3
Ging Viên: Trn Vang
(
)
==
−
=
−
=22
max cm
kg
7427,3
m
T
427,37
.100,825
2
4,5
3
2.800
.ae
2
b
3.
2.N
σ
V7$)1
D/!7*!",$!!)&$)%[!)-
)
m
T
( 1,779
3,8
1,7.0,81,8.3,0
γ
3
=
+
=
'
D5-/!"(-
=
2
'
cm
kg
3,0R
DL$&!(!"+
#
.H(#
#
(
.H(0'
D52$-
(
)
[
]
(
)
{
}
( )
[ ]
( ){ }
=−+−+⇒=
+−+=
2
21
'
cm
kg
012,533,80,3.1,779.24,50,1.13.1,2.
3Ah..k2bk1R1,2.R
γ
?*$-
=<
=
22
max
cm
kg
012,5R
cm
kg
3,7427.δ
'
O&")1)&'
"'L)1)&$&-
TP&$P9Z-
(
)
Tm660.MM
l
==
TPG-
( )
Tm.1800
2
4,5
800.
2
b
N.M
g
===
U&9\*6**$-
0,7 m0,367
1800
660
M
M
g
l
=<==
'
O&")1)&$&'
'L)1)&$!-
R)&**G6)1 (!"4M.H(N
/8&!- R.H/
/8&$!- /.>'M.SHH'H(N.0H/
U&9\*6**$-
0,8m0,6875
320
220
T
H=<==
O&"$"7!'
Bài tp tham kho môn Nn móng Trang4
Ging Viên: Trn Vang
'K)8$P)1)&
)1&69)#
1 ) )& $,$ $G $& 6 2$ $
×
" .
](N
×
+' / ! & & $P 8
$9!$2$ 1-
/8$92$->.#HHH/
/8$9)$8->
.+HH/ T
.NH/
>)1 1- U9 !) + $& !
",$
γ
#
.#(;+/
0
($\)$%&J
.H(4(
!8'U9$9$$)1N'
γ
.#(4+/
0
'U9*P
*)&J
U
.H(++6
ε
.H(4'T"7)&$7$$
?
'I)
α
.#'
5$)8&6)1!
>.#HHH/ T.>'P.#HHH'H(S.SHH/
'L)1)&&-
V7$
σ
@
-
0,833.(m)
6
5
6
b
ρ
0,8.(m)e
===
=
→
PW
ρ
O&
δ
3H'
→
XY*$'
(
)
≈=+=+=
22
2
max
cm
kg
.17,4
m
T
.7,41
9,4.5
6.800
9,4.5
1000
W
M
F
N
δ
V7$-
DLJ
.H(4'/!"N!&$$%&6'
5-/!"(
=
2
'
cm
kg
2,5.R
'
D/!"+6$&!",$
#
.H(#
#
.H(0'
D52$-
(
)
[
]
(
)
{
}
( )
[ ]
( ){ }
=−+−+⇒=
+−+=
2
21
'
cm
kg
4,845.34,50,3.1,75.250,1.12,5.1,2.
3Ah..k2bk1R1,2.R
γ
?*$-
=<
=
22
max
cm
kg
4,845R
cm
kg
.17,4δ
O&")1)&'
"'L)1)&&%&9)-U9*PJ
U
.H(++!&$P)1
)$%"79$$&6,6&9$)8!-
V7$
σ
A
-
D/!!)!",$!&$&$)-
)
m
T
1,7056(
4
5
4.65,15.75,1
4
5
4.γ5.γ
γ
3
21
tb
=
+
+
=
+
+
=
H(S
+
R
>
Z
N(+
Bài tp tham kho môn Nn móng Trang5
Ging Viên: Trn Vang
DXY*!",$-
(
)
2
m
T
21,277.
9,4.5
1000
F
N
σ===
D/!";6
1,88
5
9,4
b
a
n===
6
0,9
5
4,545
b
z
m=
−
+
==
'>*";
α
.H(+;0
→
XY*!)%&9*P-
(
)
(
)
(
)
(
)
1,75.4,5277,210,5273.5,44,51,7056.γ.hσα.zh.γσ
tbz
−
+
+
=
−
+
+
=
(
)
==
22
cm
kg
2,252.
m
T
22,523.
V7$
A
-
D59*PP)1($)&*!^
ε
.H(4'/!"#(*
-
=
2
'
cm
kg
1,25.R
D?PP)1!"+
#
.H(H
#
6
.H(#+
D "
:
."D':'0H
H
.+D'N(+'H(++;.#H( 6"
:
≤
4)$"
:
.4
$
:
.+DN.](H
→
5$7*PP-
(
)
[
]
(
)
{
}
3h..γk2bk1R1,2.R
ztb2z1
'
z
−+−+=
( )
[ ]
( ){ }
=−+−+=
2
z
cm
kg
3,462.396.0,15.1,705260,02.11,25.1,2.R
?*$-
=<
=
2
z
2
z
cm
kg
3,462.R
cm
kg
2,252.σ
'U9*P")1)&
'
'K)8!)&$'
L)&$$9&)$8&)'
( )
m0,84.
500
420
N
M
e
tc
tc
0
===
I2$-
( )
m0,83.
6
5
6
b
ρ===
U&9\*6**$-
1α1,012
0,83
0,84
ρ
e
0
=>==
'
L)&$$"'
