The compression ratio

This paper presents a new technique to design RC columns of the rectangular section, subjected to axial compression and uni- or biaxial bending. Distributed bars around the perimeter are considered as an equivalent thin tube. Using the same steel area for two separate couples of axial compression and uniaxial bending is a trick to solve the equilibrium equations for the optimum steel ratio between faces b and h.

6p vifalcon 16-05-2023 1 1   Download

Động cơ có thể thay đổi tỷ số nén linh hoạt - Variable compression ratio (VCR) là một trong những giải pháp giúp tăng công suất động cơ, giảm mức tiêu thụ nhiên liệu nhờ nâng cao hiệu suất quá trình cháy, giảm mức khí thải độc hại. Bài viết Nghiên cứu động cơ thay đổi tỉ số nén VCR giới thiệu động cơ VCR; Kết cấu và nguyên lý hoạt động của động cơ VCRi.

5p vizenvo 30-11-2022 5 2   Download

This paper presents the possible combinations of advantage factors from PFI and GDI system by applying an airassisted injector on Semi-direct Injection System (SDI). Firstly, an adaptor that uses compressed air to improve the atomization of conventional injector and reduce droplet size is made. Secondly, the modifications of intake port by using vortex plate and the other by closing one intake valve increase swirl ratio of in-cylinder air motions which help to form rich mixture around spark plug and lean mixture at other locations.

5p vispyker 16-11-2022 6 1   Download

This paper presents a study on the influence of squish area on engine performance of single cylinder natural gas converted engine. The obtained results indicated that the increase of compression ratio only augmented the risk of knocking for single cylinder natural gas converted engine.

8p viporsche 25-10-2022 2 2   Download

Natural gas is well known as a promising alternative fuel for internal combustion engine. In this study, a numerical model was built based on the experimental CNG converted engine. Direct injection and port fuel injection method was operated in the model on the same conditions such as design parameter, engine speed, compression ratio.

8p viporsche 25-10-2022 2 2   Download

The paper presents experimental results and structural analysis of reinforced concrete (RC) columns made of recycled aggregate concrete (RAC) and natural aggregate concrete (NAC) under concentric compressive load. The ratio of recycled aggregates in mixture (i.e, replacement ratio, r in %) was 0, 50, and 100% by mass, where r = 0% corresponding to NAC.

11p haoasakura 30-05-2022 8 1   Download

The EIAs disclose that even through some of the mixes provide better performance in terms of certain environmental impact categories; especially CO2 emission, water pollution (fresh and marine) and ecotoxicity, their strength to environmental impact ratios are relatively low.

12p thebadguys 15-01-2022 6 0   Download

The present research aims to investigate the influence of the ratio of reinforced concrete layer height to total height (h/H) on the mechanical properties of functionally graded concrete (FGC) containing fly ash (Fa) and polypropylene (PP) fiber. All FGC samples were prepared with a constant water-to-cementitious materials ratio of 0.36 and ordinary Portland cement was replaced with Fa at 20% by mass.

14p inception36 30-11-2021 4 1   Download

This paper presents a numerical analysis of the seismic behavior of square concrete filled steel tubular (CFST) columns. Finite element analysis (FEA) models in ABAQUS software were used to simulate a series of columns subjected to axial compression and cyclic lateral loading. The CFST columns were simulated using nonlinear tri-dimensional (3-D) finite elements for the infilled concrete, and nonlinear two-dimensional (2-D) finite elements for the steel tube.

14p chauchaungayxua12 09-07-2021 16 0   Download

In order to reduce the serious impacts of industrial and agricultural wastes on the environment, raw rice husk and bottom ash were used as fine aggregates, while fly ash was utilized as a binder material in the production of unburnt building bricks. Two group mixtures were designed with water-to-binder (W/B) ratios of 0.30 and 0.35. The rice husk was used to replace 0%, 3%, 6%, and 9% of bottom ash content by mass.

11p chauchaungayxua12 09-07-2021 4 0   Download

In this paper, a numerical Discrete Element Method (DEM) model was calibrated to investigate the transmission of force in granular media. To this aim, DEM simulation was performed for reproducing the behavior of a given granular material under uniform compression. The DEM model was validated by comparing the obtained shear stress/normal stress ratio with results published in the available literature. The network of contact forces was then computed, showing the arrangement of the material microstructure under applied loading...

19p nguaconbaynhay11 07-04-2021 15 1   Download

Current glenoid defect measurement techniques only quantify bone loss in terms of defect diameter or surface. However, the glenoid depth plays an important role in shoulder stabilization by means of concavity compression.

5p vioregon2711 22-02-2021 7 1   Download

Vertebral augmentation is the first-line treatment for the osteoporosis vertebral compression fractures. Bone cement leakage is the most common complication of this surgery. This study aims to assess the risk factors for different types of cement leakage and provides a nomogram for predicting the cement intradiscal leakage.

8p vimariana2711 22-12-2020 6 0   Download

Chapter 3 - Axially loaded members. The following will be discussed in this chapter: Normal stress and normal strain, tension and compression test, poisson’s ratio, shearing strain, allowable stress – factor of safety, statically indeterminate problem.

43p larachdumlanat122 28-11-2020 24 0   Download

In this study, GGBFS at different cement replacement ratios of 0%, 20%, 40% and 60% by weight were used in finegrained concrete. The ternary binders containing GGBFS and FA at cement replacement ratio of 60% by weight have also evaluated. Flexural and compressive strength test, rapid chloride permeability test and under-water abrasion test were performed. Experimental results show that the increase in concrete strength with GGBFS contents from 20% to 40% but at a higher period of maturity (56 days and more).

14p kequaidan8 02-11-2020 7 0   Download

In this research, the performance of a cementless eco-binder, a mixture of waste materials including slag, circulating fluidized bed combustion ash (CFA), and rice husk ash (RHA) was investigated, in which CFA acted as an activator. One hundred and twenty paste samples were prepared by using the RHA/(slag + RHA) ratios of 0, 15, 30, 45% while keeping a constant ratio of CFA/(slag + RHA) at 25%. The setting period, compressive strength, the ultrasonic pulse velocity (UPV), and drying shrinkage of paste samples were determined at the samples’ age of up to 91 days.

13p cothumenhmong8 04-11-2020 8 0   Download

This research deals with the influences of macro, meso and micro steel-smooth fibers on tensile and compressive properties of strain-hardening fiber-reinforced concretes (SFCs). The different sizes, indicated by length/diameter ratio, of steel-smooth fiber added in plain matrix (Pl) were as follows: 30/0.3 for the macro (Ma), 19/0.2 for the meso (Me) and 13/0.2 for the micro fiber (Mi). All SFCs were used the same fiber volume fraction of 1.5%.

12p cothumenhmong8 04-11-2020 11 1   Download

With the reduction of gene sequencing cost and demand for emerging technologies such as precision medical treatment and deep learning in genome, it is an era of gene data outbreaks today. How to store, transmit and analyze these data has become a hotspot in the current research. Now the compression algorithm based on reference is widely used due to its high compression ratio.

12p viconnecticut2711 28-10-2020 9 1   Download

Advanced sequencing machines dramatically speed up the generation of genomic data, which makes the demand of efficient compression of sequencing data extremely urgent and significant. As the most difficult part of the standard sequencing data format FASTQ, compression of the quality score has become a conundrum in the development of FASTQ compression.

12p vicolorado2711 22-10-2020 12 0   Download

The main aim of this paper is to determine temperature distribution in a four-stroke, single-cylinder, water cooled, variable compression ratio (3-9), variable speed (2200-3000 rpm) spark ignition engine with brake power of 2.2 kW at a speed of 3000 rpm with copper coated combustion chamber (CCE) [copper-(thickness, 300 μ) was coated on piston crown, inner side of liner and cylinder head] and compared the engine, with conventional combustion chamber (CE) with neat gasoline operation. Copper coated power piston, copp.

8p cleopatrahuynh 01-06-2020 10 0   Download