• Steel and Composite Structures
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• v.27 no.4
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• pp.495-508
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• 2018

In this paper, cyclic loading tests on composite frame inner joints of steel-reinforced recycled concrete (SRRC) column-steel beam were conducted. The main objective of the test was to obtain the shear behavior and analyze the shear strength of the joints. The main design parameters in the test were recycled coarse aggregate (RCA) replacement percentage and axial compression ratio. The failure process, failure modes, hysteresis curves and strain characteristics of the joints were obtained, and the influences of design parameters on the shear strength of the joints have been also analysed in detail. Results show that the failure modes of the joints area are typical shear failure. The shear bearing capacity of the joints maximally decreased by 10.07% with the increase in the RCA replacement percentage, whereas the shear bearing capacity of the joints maximally increased by 16.6% with the increase in the axial compression ratio. A specific strain analysis suggests that the shear bearing capacity of the joints was mainly provided by the three shear elements of the recycled aggregate concrete (RAC) diagonal compression strut, steel webs and stirrups of the joint area. According to the shear mechanism and test results, the calculation formulas of the shear bearing capacity of the three main shear elements were deduced separately. Thus, the calculation model of the shear bearing capacity of the composite joints considering the adverse effects of the RCA replacement percentage was established through a superposition method. The calculated values of shear strength based on the calculation model were in good agreement with the test values. It indicates that the calculation method in this study can reasonably predict the shear bearing capacity of the composite frame inner joints of SRRC column-steel beam.

• Journal of the Korean Geosynthetics Society
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• v.13 no.2
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• pp.41-47
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• 2014

Various prediction methods for the bearing capacity of helical piles have been introduced with consideration of both the steel shaft and the helix plates attached to the shaft. In this paper, three representative methods, that is, individual bearing method, cylindrical shear method, and torque correlation method are discussed and compared to each other. The prediction methods were verified by comparing with a series of loading test results performed on moderate-size helical piles from the companion paper. As a result, the measured bearing capacity is greater than the bearing capacity predicted by the cylindrical shear method, but smaller than that of the individual bearing method. In addition, the bearing capacity predicted by the torque correlation method is in good agreement with the measured bearing capacity.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.78-91
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• 2024

Double steel plate concrete composite shear wall (SCSW) has been widely utilized in nuclear power plants and high-rise structures, and its shear connectors have a substantial impact on the seismic performance of SCSW. Therefore, in this study, the mechanical properties of SCSW with angle stiffening ribs as shear connections were parametrically examined for the reactor containment structure of nuclear power plants. The axial compression ratio of the SCSW, the spacing of the angle stiffening rib arrangement and the thickness of the angle stiffening rib steel plate were selected as the study parameters. Four finite element models were constructed by using the finite element program named ABAQUS to verify the experimental results of our team, and 13 finite element models were established to investigate the selected three parameters. Thus, the shear capacity, deformation capacity, ductility and energy dissipation capacity of SCSW were determined. The research results show that: compared with studs, using stiffened ribs as shear connectors can significantly enhance the mechanical properties of SCSW; When the axial compression ratio is 0.3-0.4, the seismic performance of SCSW can be maximized; with the lowering of stiffener gap, the shear bearing capacity is greatly enhanced, and when the gap is lowered to a specific distance, the shear bearing capacity has no major affect; in addition, increasing the thickness of stiffeners can significantly increase the shear capacity, ductility and energy dissipation capacity of SCSW. With the rise in the thickness of angle stiffening ribs, the improvement rate of each mechanical property index slows down. Finally, the shear bearing capacity calculation formula of SCSW with angle stiffening ribs as shear connectors is derived. The average error between the theoretical calculation formula and the finite element calculation results is 8% demonstrating that the theoretical formula is reliable. This study can provide reference for the design of SCSW.

• Steel and Composite Structures
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• v.28 no.1
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• pp.73-82
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• 2018

This paper experimentally and analytically elucidates the shear behavior and shear bearing capacity of partially prefabricated steel reinforced concrete (PPSRC) columns and hollow partially prefabricated steel reinforced concrete (HPSRC) columns. Seven specimens including five PPSRC column specimens and two HPSRC column specimens were tested under static monotonic loading. In the test, the influences of shear span aspect ratio and difference of cast-in-place concrete strength on the shear behavior of PPSRC and HPSRC columns were investigated. Based on the test results, the failure pattern, the load-displacement behavior and the shear capacity were focused and analyzed. The test results demonstrated that all the column specimens failed in shear failure mode with high bearing capacity and good deformability. Smaller shear span aspect ratio and higher strength of inner concrete resulted in higher shear bearing capacity, with more ductile and better deformability. Furthermore, calculation formula for predicting the ultimate shear capacity of the PPSRC and HPSRC columns were proposed on the basis of the experimental results.

• Tribology and Lubricants
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• v.30 no.5
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• pp.284-290
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• 2014

The influence of round embossed surface on slider bearing characteristics and its load carrying capacity is discussed for thin film effect of embossed slider bearing. For the numerical computation of lubrication parameters such as pressure, load capacity and shear stress that are normalized and a Reynolds equation is used for the analysis of embossed slider bearing characteristics. For this purpose, the finite difference method of central difference scheme is used in this study. In a slider bearing with embossed form, several simulation parameters such as pressure, load capacity and shear stress of the bearing can be obtained according to independent parameters such as the slope of the slider bearing and number of embossing in the upper slider. Also this results can be summarized and be stored in sequential data file for latter analysis. After all, their distribution of the pressure and shear stress parameters can be displayed and be analyzed easily by using the developed program with matlab GUI technique. The independent parameters such as a number of embossing and a slope of the embossed surface slider are used for discussing simulation parameters of pressure distribution, shear stress and load carrying capacity of the round embossing. These study results reported in this paper should be applied to the other shaped slider bearing with a rectangular embossed surface or rectangular waved surface.

• Steel and Composite Structures
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• v.44 no.5
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• pp.677-684
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• 2022

This paper reports experimental investigation on shear behavior of steel reinforced concrete (SRC) shallow floor beam, where the steel shape is embedded in concrete and the high strength bolts are used to transfer the shear force along the interface between the steel shape and concrete. Six specimens were conducted aiming to provide information on shear performance and explore the shear bearing capacity of SRC shallow floor beams. The effects of the height of concrete slab, the size and the type of the steel section on shear performance of beams were also analyzed in the test. Based on the strut-and-tie model, the shear strength of the SRC shallow floor beam was proposed. Experimental results showed that composite shallow floor beam exhibited satisfactory composite behavior and all of the specimen failed in shear failure. The shear bearing capacity increased with the increasing of height of concrete slab and the size of steel shape, and the bearing capacities of beam specimens with castellated steel shape was slightly lower than those of specimens with H-shaped steel section. Furthermore, the calculations for evaluating the shear bearing capacity of SRC shallow floor beam were verified to be reasonable.

• Structural Engineering and Mechanics
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• v.90 no.4
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• pp.345-356
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• 2024

This paper aims to investigate the seismic behavior of double steel plate and concrete composite shear wall (DSCW) of shield buildings in nuclear power engineering through experimental study. Hence, a total of 10 specimens were tested to investigate the hysteretic performance of DSCW specimens in detail, in terms of load vs. displacement hysteretic curves, skeleton curves, failure modes, flexural strength, energy dissipation capacity. The experimental results indicated that the thickness of steel plate, vertical load and stiffener have great influence on the shear bearing capacity of shear wall, and the stud space has limited influence on the shear capacity. And finally, a novel simplified formula was proposed to predict the shear bearing capacity of composite shear wall. The predicted results showed satisfactory agreement with the experimental results.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.367-372
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• 2002

In these days, The base isolation system is often used to improve the seismic capacity of the structures instead of conventional techniques of strengthening the structural members. The purpose of this study is to evaluate dynamic properties and mechanical characteristics of the 10tonf-LRB(Lead-Rubber Bearing). Experimental studies were performed to obtain the hysteretic behavior, effective shear stiffness( $K_{eff}$), equivalent damping( $H_{eq}$ ), capacity of energy dissipation( $W_{D}$) of six 10tonf-LRB. Especially, in this study, the response of the LRB for high loading frequency(0.5Hz~3.0Hz) was estimated. The effective shear stiffness of the LRB decreases and the capacity of energy dissipation increases as the shear strain amplitude increases. But the shear behavior of the LRB is not affected sensitively by loading frequency.y.y.

• International journal of steel structures
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• v.18 no.4
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• pp.1210-1218
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• 2018

A new type of earthquake-resisting element that consists of a steel plate shear wall with slits is introduced. The infill steel plate is divided into a series of vertical flexural links with vertical links. The steel plate shear walls absorb energy by means of in-plane bending deformation of the flexural links and the energy dissipation capacity of the plastic hinges formed at both ends of the flexural links when under lateral loads. In this paper, finite element analysis and experimental studies at low cyclic loadings were conducted on specimens with steel plate shear walls with multilayer slits. The effects caused by varied slit pattern in terms of slit design parameters on lateral stiffness, ultimate bearing capacity and hysteretic behavior of the shear walls were analyzed. Results showed that the failure mode of steel plate shear walls with a single-layer slit was more likely to be out-of-plane buckling of the flexural links. As a result, the lateral stiffness and the ultimate bearing capacity were relatively lower when the precondition of the total height of the vertical slits remained the same. Differently, the failure mode of steel plate shear walls with multilayer slits was prone to global buckling of the infill steel plates; more obvious tensile fields provided evidence to the fact of higher lateral stiffness and excellent ultimate bearing capacity. It was also concluded that multilayer specimens exhibited better energy dissipation capacity compared with single-layer plate shear walls.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.565-573
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• 2004

This study is to present explicit analytical expressions for calculating bearing capacity factor $N_{\gamma}$, to provide results of the numerical computation instead of the graphical method. In this study, $N_{\gamma}$ is proposed in the critical failure surface on assumption that the center of log spiral in the radial shear zone can be located at the any points of around footing. The critical failure surface is one which yields minimum passive pressure $P_{\gamma}$ on the radial shear zone from the family of log spirals accoding to change of the center of log spiral. This study adoptes Terzaghi's bearing capacity principle(e.g., Prandtl's mechanism, limit equilibrium equation, superposition principle) but the soil wedge in an elastic zone makes angle $45^{\circ}+{\phi}/2$ with the horizontal and the location of the log spiral's center.