• Title/Summary/Keyword: cross-sectional capacity

Search Result 177, Processing Time 0.025 seconds

Muscle Fiber Characteristics and Their Relationship to Water Holding Capacity of Longissimus dorsi Muscle in Brahman and Charolais Crossbred Bulls

  • Waritthitham, A.;Lambertz, C.;Langholz, H.-J.;Wicke, M.;Gauly, M.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.23 no.5
    • /
    • pp.665-671
    • /
    • 2010
  • Muscle fiber characteristics and their relationship to water-holding capacity of longissimus dorsi (ld) muscle were studied in Brahman (BRA) and Charolais (CHA) crossbred bulls fattened under practical farm conditions. Thirty-four BRA and 34 CHA bulls were randomly selected and slaughtered at 500, 550 and 600 kg live weight. Parameters of water-holding capacity such as drip, ageing, thawing, cooking and grilling loss were determined. Muscle fiber characteristics were conducted for muscle fiber type percentage and cross-sectional areas of slow- and fast-twitch fiber types, and correlation coefficients to water-holding capacity parameters were calculated. Results showed that CHA meat had a better water-holding capacity (less ageing, thawing and grilling loss) when compared with BRA, whereas slaughter weights had no significant effects on these parameters. Furthermore, there were no significant differences between genotypes and slaughter weights in muscle fiber type percentage and cross-sectional areas of ld muscle. Slow- and fast-twitch fiber types of all experimental groups averaged 24.4 and 75.6%, respectively. Cross-sectional areas of fast-twitch fibers had almost twice the size of slow-twitch fibers (6,721 and 3,713 ${\mu}m^2$, respectively). The correlation between muscle fiber area and water-holding capacity indicated that muscles with larger fiber areas had a lower drip and ageing loss but a higher cooking and grilling loss.

Displacement Dependency and Capacity Evaluation According to the Cross-Sectional Shape and Aspect Ratio of Steel Rod Dampers (강봉댐퍼의 단면형상과 형상비에 따른 변위의존성 및 성능 평가)

  • Hyun-Ho Lee
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.27 no.5
    • /
    • pp.89-96
    • /
    • 2023
  • In this study, the displacement dependence, strength, and energy dissipation capacity of the steel rod damper were evaluated. The test variables were cross-sectional shape and aspect ratio. The 6th test specimens were made for performance test. From the test results, it was evaluated that the displacement dependence conditions of design code were satisfied in all specimens. And the strength effect according to the cross-sectional shape was minimal. As a result, the strength and energy dissipation capacity of the aspect ratio of 13.7 were evaluated as excellent.

Applicability of Cross Shaped Drain to Soft Clay Improvement (십자형 연직배수재의 점성토지반 개량에의 적용성)

  • 장연수;김영우;김수삼
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.09a
    • /
    • pp.9-16
    • /
    • 2000
  • Applicability of the cross shaped drain in a soft clay ground is examined using the laboratory discharge capacity test, column consolidation test and 3-D numerical flow analysis. The equivalent diameter of the tested drains is back-calculated from the laboratory experiment and compared with those calculated from the formula suggested in the literature. The effective range of the cross shaped drain about the discharge capacity and coefficient of permeability is analyzed. The results of numerical analysis show that the cross shaped drain which has a cross-sectional area twice of the band shaped drain can reduce the consolidation time by 30% from that for the band shaped drain in a soft clay ground that K is over 1${\times}$10$\^$-7/cm/sec

  • PDF

A numerical analysis on the performance of buckling restrained braces at fire-study of the gap filler effect

  • Talebi, Elnaz;Tahir, Mahmood Md.;Zahmatkesh, Farshad;Kueh, Ahmad B.H.
    • Steel and Composite Structures
    • /
    • v.19 no.3
    • /
    • pp.661-678
    • /
    • 2015
  • Buckling Restrained Braces (BRB) have been widely used in the construction industry as they utilize the most desirable properties of both constituent materials, i.e., steel and concrete. They present excellent structural qualities such as high load bearing capacity, ductility, energy-absorption capability and good structural fire behaviour. The effects of size and type of filler material in the existed gap at the steel core-concrete interface as well as the element's cross sectional shape, on BRB's fire resistance capacity was investigated in this paper. A nonlinear sequentially-coupled thermal-stress three-dimensional model was presented and validated by experimental results. Variation of the samples was described by three groups containing, the steel cores with the same cross section areas and equal yield strength but different materials (metal and concrete) and sizes for the gap. Responses in terms of temperature distribution, critical temperature, heating elapsed time and contraction level of BRB element were examined. The study showed that the superior fire performance of BRB was obtained by altering the filler material in the gap from metal to concrete as well as by increasing the size of the gap. Also, cylindrical BRB performed better under fire conditions compared to the rectangular cross section.

Experiments on the bearing capacity of tapered concrete filled double skin steel tubular (CFDST) stub columns

  • Ren, Qing-Xin;Hou, Chao;Lam, Dennis;Han, Lin-Hai
    • Steel and Composite Structures
    • /
    • v.17 no.5
    • /
    • pp.667-686
    • /
    • 2014
  • Tapered concrete filled double skin steel tubular (CFDST) columns have been used in China for structures such as electricity transmission towers. In practice, the bearing capacity related to the connection details on the top of the column is not fully understood. In this paper, the experimental behaviour of tapered CFDST stub columns subjected to axial partial compression is reported, sixteen specimens with top endplate and ten specimens without top endplate were tested. The test parameters included: (1) tapered angle, (2) top endplate thickness, and (3) partial compression area ratio. Test results show that the tapered CFDST stub columns under axial partial compression behaved in a ductile manner. The axial partial compressive behaviour and the failure modes of the tapered CFDST stub columns were significantly influenced by the parameters investigated. Finally, a simple formula for predicting the cross-sectional capacity of the tapered CFDST sections under axial partial compression is proposed.

Efficient influence of cross section shape on the mechanical and economic properties of concrete canvas and CFRP reinforced columns management using metaheuristic optimization algorithms

  • Ge, Genwang;Liu, Yingzi;Al-Tamimi, Haneen M.;Pourrostam, Towhid;Zhang, Xian;Ali, H. Elhosiny;Jan, Amin;Salameh, Anas A.
    • Computers and Concrete
    • /
    • v.29 no.6
    • /
    • pp.375-391
    • /
    • 2022
  • This paper examined the impact of the cross-sectional structure on the structural results under different loading conditions of reinforced concrete (RC) members' management limited in Carbon Fiber Reinforced Polymers (CFRP). The mechanical properties of CFRC was investigated, then, totally 32 samples were examined. Test parameters included the cross-sectional shape as square, rectangular and circular with two various aspect rates and loading statues. The loading involved concentrated loading, eccentric loading with a ratio of 0.46 to 0.6 and pure bending. The results of the test revealed that the CFRP increased ductility and load during concentrated processing. A cross sectional shape from 23 to 44 percent was increased in load capacity and from 250 to 350 percent increase in axial deformation in rectangular and circular sections respectively, affecting greatly the accomplishment of load capacity and ductility of the concentrated members. Two Artificial Intelligence Models as Extreme Learning Machine (ELM) and Particle Swarm Optimization (PSO) were used to estimating the tensile and flexural strength of specimen. On the basis of the performance from RMSE and RSQR, C-Shape CFRC was greater tensile and flexural strength than any other FRP composite design. Because of the mechanical anchorage into the matrix, C-shaped CFRCC was noted to have greater fiber-matrix interfacial adhesive strength. However, with the increase of the aspect ratio and fiber volume fraction, the compressive strength of CFRCC was reduced. This possibly was due to the fact that during the blending of each fiber, the volume of air input was increased. In addition, by adding silica fumed to composites, the tensile and flexural strength of CFRCC is greatly improved.

Layered Section Analysis for PSC Girder with Variable Cross Section Using SI Technique (SI기법을 이용한 변단면 PSC 거더의 층상화 단면해석)

  • Kim, Byeong Hwa;Park, Taehyo;Jeon, Hye-Kwan
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.30 no.6A
    • /
    • pp.581-590
    • /
    • 2010
  • This study introduces a layered sectional analysis for a PSC girder with a vaiable cross section and curved tendons. To consider the shear equilibrium at a concrete layer with curved tendons, the shear stress distribution has been computed at each section. In addition, to improve the convergence to the solution, a system identification technique is newly adopted in the solution process for strain computation. To examine the feasibility of the proposed approach, a static load test has been conducted for a full scale PSC girder with variable cross section. The prediction shows a good agreement with experiment. It is seen that a uniform cross section has the same moment capacity with a variable cross section while the variable cross section has more shear capacity than the uniform cross section. It is also noted that the maximum displacement of a variable cross section is a little smaller than a uniform cross section.

CFD Analysis of Trap Effect of Groove in Lubricating Systems: Part I - Variation in Cross-Sectional Shape of Groove (그루브의 Trap 효과에 대한 CFD 해석: 제 1부 − 그루브 단면 형상의 변화)

  • Hong, Sung-Ho
    • Tribology and Lubricants
    • /
    • v.32 no.3
    • /
    • pp.101-105
    • /
    • 2016
  • Trap effect of groove is evaluated in a lubricating system using computational fluid dynamics (CFD) analysis. The simulation is based on the standard k-ε turbulence model and the discrete phase model (DPM) using a commercial CFD code FLUENT. The simulation results are also capable of showing the particle trajectories in flow field. Computational domain is meshed using the GAMBIT pre-processor. The various grooves are applied in order to improve lubrication characteristics such as reduction of friction loss, increase in load carrying capacity, and trapping of the wear particles. Trap effect of groove is investigated with variations in cross-sectional shape and Reynolds number in this research. Various cross-sectional shapes of groove (rectangular, triangle, U shaped, trapezoid, elliptical shapes) are considered to evaluate the trap effect in simplified two-dimensional sliding bearing. The particles are assumed to steel, and defined a single particle injection condition in various positions. The “reflect” boundary condition for discrete phase is applied to the wall boundary, and the “escape” boundary condition to “pressure inlet” and “pressure outlet” conditions. The streamlines are compared with particles trajectories in the groove. From the results of numerical analysis in the study, it is found that the cross-sectional shapes favorable to the creation of vortex and small eddy current are effective in terms of particle trapping effect. Moreover, it is found that the Reynolds number has a strong influence on the pattern of vortex or small eddy current in the groove, and that the pattern of the vortex or small eddy current affects the trap effect of the groove.

Heat transfer and pressure drop with the turbulence promoter in a vertical PCB Channel (난류 발생기의 형상에 따른 수직 PCB채널에서의 열전달 및 압력손실 변화)

  • Park, Chan-U;Jang, Seung-Il;Jeong, Jong-Su;Nam, Pyeong-U
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.20 no.7
    • /
    • pp.2277-2288
    • /
    • 1996
  • This study was performed to analyze the cooling effect of heated ribs which are frequently used for cooling of electronic parts, using the numerical method. To prevent the excessive pressure drop due to turbulence promoters for the enhancement of heat transfer rate especially, the effect of the angle of turbulence promoter was investigated by the numerical analysis. Heat transfer rate with turbulence promoters with rectangular cross-section increased by 13% in average, but the coefficient of pressure drop increased by 1.68 times than that without them. In the present study, triangular cross-sectional shape turbulence promoters were suggested and numerically tested. Pressure drop of turbulence promoter with the 30 degree triangular cross-sectional shape decreased by 30% from that of rectangular cross-section promoters while heat transfer rate was almost the same. While with 4 turbulence promoters, the heat transfer rate increased by 21%, the pressure drop increased 4 times. It means that the higher capacity of cooling fan should be needed. With the triangular cross-sectional shape, the size of vortex region at the rear of promoters became considerably smaller, so pressure drop became smaller. The effect of the change of cross-sectional shape was not found in the flow pattern near the ribs, so that heat transfer characteristics in the ribs were not changed.

Behavior of lightweight aggregate concrete voided slabs

  • Adel A. Al-Azzawi;Ali O, AL-Khaleel
    • Computers and Concrete
    • /
    • v.32 no.4
    • /
    • pp.351-363
    • /
    • 2023
  • Reducing the self-weight of reinforced concrete structures problem is discussed in this paper by using two types of self-weight reduction, the first is by using lightweight coarse aggregate (crushed brick) and the second is by using styropor block. Experimental and Numerical studies are conducted on (LWAC) lightweight aggregate reinforced concrete slabs, having styropor blocks with various sizes of blocks and the ratio of shear span to the effective depth (a/d). The experimental part included testing eleven lightweight concrete one-way simply supported slabs, comprising three as reference slabs (solid slabs) and eight as styropor block slabs (SBS) with a total reduction in cross-sectional area of (43.3% and 49.7%) were considered. The holes were formed by placing styropor at the ineffective concrete zones in resisting the tensile stresses. The length, width, and thickness of specimen dimensions were 1.1 m, 0.6 m, and 0.12 m respectively, except one specimen had a depth of 85 mm (which has a cross-sectional area equal to styropor block slab with a weight reduction of 49.7%). Two shear spans to effective depth ratios (a/d) of (3.125) for load case (A) and (a/d) of (2) for load case (B), (two-line monotonic loads) are considered. The test results showed under loading cases A and B (using minimum shear reinforcement and the reduction in cross-sectional area of styropor block slab by 29.1%) caused an increase in strength capacity by 60.4% and 54.6 % compared to the lightweight reference slab. Also, the best percentage of reduction in cross-sectional area is found to be 49.7%. Numerically, the computer program named (ANSYS) was used to study the behavior of these reinforced concrete slabs by using the finite element method. The results show acceptable agreement with the experimental test results. The average difference between experimental and numerical results is found to be (11.06%) in ultimate strength and (5.33%) in ultimate deflection.