• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.6
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• pp.547-554
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• 2016

In this study, nonlinear finite element analysis based on the Modified Compression Field Theory has been conducted to evaluate shear strength of RC walls with opening. On the analysis, reinforcement ratio within development length of rebars nearby the opening was reduced in the model in order to investigate the effect of opening on shear strength of RC shear walls. The nonlinear finite element analysis has been verified through comparison with the test result in literature. Through the verification, it was investigated that the analysis considering the development length of rebars well reflected the effect of an opening on shear strength of RC shear walls while current design provisions did not reasonably consider one.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.2
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• pp.1-8
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• 2014

The present study proposes a simple equation to straightforwardly determine the potential plastic hinge length in boundary element of reinforced concrete shear walls. From the idealized curvature distribution along the shear wall length, a basic formula was derived as a function of yielding moment, maximum moment, and additional moment owing to diagonal tensile crack. Yielding moment and maximum moment capacities of shear wall were calculated on the basis of compatability of strain and equilibrium equation of internal forces. The development of a diagonal tensile crack at web was examined from the shear transfer capacity of concrete specified in ACI 318-11 provision and then the additional moment was calculated using the truss mechanism along the crack proposed by Park and Paulay. The moment capacities were simplified from an extensive parametric study; as a result, the equivalent plastic hinge length of shear walls could be formulated using indices of longitudinal tensile reinforcement at the boundary element, vertical reinforcement at web, and applied axial load. The proposed equation predicted accurately the measured plastic hinge length, providing that the mean and standard deviation of ratios between predictions and experiments are 1.019 and 0.102, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.3
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• pp.128-137
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• 2012

In high multistory buildings, hybrid coupled shear walls can provide an efficient structural system to resist horizontal force due to wind and seismic loads. Hybrid coupled shear walls are usually built over the whole height of the building and are laid out either as a series of walls coupled by steel beams with openings to accommodate doors, elevator walls, windows and corridors. In this paper, the behavior characteristics of hybrid coupled shear wall system considering connection details is examined through results of an experimental research program where 5 two-thirds scale specimens were tested under cyclic loading. Such connections details are typically employed in hybrid coupling wall system consisting of steel coupling beams and reinforced concrete shear wall. The test variables of this study are embedment length of steel coupling beam and wall thickness of concrete shear wall. The results and discussion presented in this paper provide fundamental data for seismic behavior of hybrid coupled shear wall systems.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.1 s.71
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• pp.63-71
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• 2006

This study presents the effective stiffness-based optimal technique to control Quantitatively lateral drift for shear wall-frame structure system using sensitivity analysis. To this end, the element stiffness matrices are constituted to solve the compatibility problem of displacement degree of freedom between the frame and shear wall. Also, lateral drift constraint to introduce the approximation concept that can preserve the generality of the mathematical programming and can effectively solve the large scaled problems is established. And, the section property relationships for shear wall and frame members are considered in order to reduce the number of design variables and differentiate easily the stiffness matrices. Specifically, constant-shape assumption which is uniformly varying in size during optimal process is applied in frame structure. The thickness or length of shear wall can be changed depending on user's intent. Two types of 20 story shear wall-frame structure system are presented to illustrate the features of the stiffness-based optimal design technique.

• Journal of the Earthquake Engineering Society of Korea
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• v.16 no.5
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• pp.23-32
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• 2012

Research on steel plate concrete (SC) structures for the modularization of nuclear power plants have been performed recently in Korea. In this study, the seismic capacity and stiffness characteristics of unstiffened SC shear walls under the effects of earthquakes were investigated through static pushover tests. Failure modes, sectional strength, and stiffness characteristics of SC structures under lateral loads were inspected by analyzing the experimental results. The strengths obtained by the experiments were also compared with those derived by the design code of the SC structures. One of the main failures of unstiffened SC shear walls was found to be the type of bending shear failure due to the debonding of the steel plate at the concrete interface. The ductility capacity of SC structures was also confirmed to be improved, which is considered to be a confining effect on steel plates in the longitudinal behavior of SC structures.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5A
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• pp.267-275
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• 2012

This paper describes the experimental study on the structural behavior of the joint plane between a RC(Reinforced Concrete) wall and a SC(Steel Plate Concrete) wall under out-of plane flexural loads and in-plane shear loads. The test specimens were produced with L and I shape to assess efficiently flexural and shear behavior of the structures. In order to consider dynamic loads such as earthquake, cyclic loading tests were carried out. As results of the out-of plane flexural tests, ductile failure mode of vertical bars was shown under a push load and the failure load was more than nominal strength of the specimen. And the latter test was performed to verify the variation which was composition presence of horizontal bars in the SC member. The test results showed that capacity of the specimens was more than their nominal strength regardless of composition presence of horizontal bars.

• Journal of the Korea Concrete Institute
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• v.23 no.5
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• pp.569-579
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• 2011

Reinforced concrete walls subjected to cyclic loading show complicated inelastic behaviors varying with aspect ratio, re-bar detail, and loading condition. In the present study, a macro model for nonlinear analysis of reinforced concrete walls was developed. For exact prediction of inelastic flexure-compression and shear behaviors, the macro model of the wall was idealized with longitudinal and diagonal uniaxial elements. The uniaxial elements consist of concrete and re-bars. Simplified cyclic models for concrete and re-bars under uniaxial loading was used. For verification, the proposed model was applied to slender, lowrise, and coupled walls subjected to cyclic loading. The results showed that the proposed method predicted the nonlinear behaviors of the walls with reasonable precision.

• Journal of the Society of Disaster Information
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• v.12 no.2
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• pp.144-149
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• 2016

Nowaday, most of the low-rise concrete structures which have less than five stories were built before the intensified seismic code was established 2005. According to the fact that our country is not a safety zone ay more, studies are need to reinforce the seismic performance of that structures. The basic frame of low-rise structure are consist of beams and columns with partition walls, therefore that are very weak about secondary wave of earthquake because of the high stiffness. The partition wall are consist of open channel for sunlight or ventilation and intermediate wall. The intermediate walls will enhance the stiffness of columns, but will cause shear failure with short column effects because of the reduced effective depth. But we don't have studies and adequate design code for partition wall effects, therefore some more studies are need for these facts.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.83-91
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• 2017

In order to cope with the abnormally high waves during the storm surge due to climate change, various methods have been proposed for interlocking adjacent caissons to enhance stability of harbor structures. Among the methods, it was studied the method based on an open-cell caisson having reduction effect increasing the cohesion with adjunction caissons by filling materials such as crushed rocks in an inter-cell formed by two facing open-cells which consist of transverse walls. It is necessary to investigate the shear behaviors of an inter-cell to secure the stability using calculating shear forces on inter-cell under oblique wave loadings. It was analyzed the shear force share ratio with the length of internal and external wall and the number of internal walls. Numerical results show that 60~70% of the shear load is transmitted to adjacent caisson through the internal walls, more than 30% is through the external wall. It was applicable in the assumption that filling materials was uniformly distributed in inter-cells, and further studies were worth consideration on other conditions under construction.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.169-172
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• 2008

Longitudinal elongation develops in reinforced concrete beams that exhibit flexural yielding during cyclic loading. The longitudinal elongation can decrease the shear strength and deformation capacity of the beams. In the present study, nonlinear truss model analysis was performed to study the elongation mechanism of reinforced concrete beams. The results showed that residual tensile plastic strain of the longitudinal reinforcing bar in the plastic hinge is the primary factor causing the member elongation, and that the shear-force transfer mechanism of diagonal concrete struts has a substantial effect on the magnitude of the elongation. Based on the analysis results, a simplified method for evaluating member elongation was developed. The proposed method was applied to test specimens with various design parameters and loading conditions..