• Earthquakes and Structures
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• v.26 no.6
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• pp.449-461
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• 2024

The vertical reinforcement connection between the precast reinforced concrete shear wall and the cast-in-place reinforced concrete member is vital to the performance of shear walls under seismic loading. This paper investigated the structural behavior of three precast reinforced concrete shear walls, with different levels of connection (i.e., full connection, partial connection, and no connection), subjected to quasi-static lateral loading. The specimens were subjected to a constant vertical load, resulting in an axial load ratio of 0.4. The crack pattern, failure modes, load-displacement relationships, ductility, and energy dissipation characteristics are presented and discussed. The resultant seismic performances of the three tested specimens were compared in terms of skeleton curve, load-bearing capacity, stiffness, ductility, energy dissipation capacity, and viscous damping. The seismic performance of the partially connected shear wall was found to be comparable to that of the fully connected shear wall, exhibiting 1.7% and 3.5% higher yield and peak load capacities, 9.2% higher deformability, and similar variation in stiffness, energy dissipation capacity and viscous damping at increasing load levels. In comparison, the seismic performance of the non-connected shear wall was inferior, exhibiting 12.8% and 16.4% lower loads at the yield and peak load stages, 3.6% lower deformability, and significantly lower energy dissipation capacity at lower displacement and lower viscous damping.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.185-190
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• 2001

The severe shortage of the available sites in the highly developed downtown area in Korea necessitates the construction of high-rise buildings which meet the need of residence and commercial activity simultaneously. The objective of this study is to investigate the seismic performance of this type of building structures. For this purpose, two 1:12 scale 17-story reinforced concrete model structures were constructed according to the similitude law, in which the upper 15 stories have a bearing-wall system while the lower 2-story frames with infilled shear wall have two different layouts of the plan : The one has symmetric plan and the other has unsymmetric plan. Then, this model was subjected to a series of earthquake excitations. The test results show that the layout of shear wall has the negligible effect on the natural period and the base shear coefficient, but great effect on the failure mode of beam-column joint at flexible side frame.

• Computers and Concrete
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• v.19 no.2
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• pp.179-189
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• 2017

Concrete shear walls are one of the major structural lateral resisting systems in buildings. In some cases, due to the change in the occupancy of the structure or functional requirements like architectural and even mechanical ones, openings need to be provided and installed in structural walls after their construction. Providing these openings may significantly influence the structural behavior of the constructed wall. This paper considers the results of a nonlinear finite element analysis of shear walls with opening strengthened by carbon fiber reinforced polymer (CFRP) strips with different configurations. Details of bond-slip constitutive model of link elements to simulate the connections of FRP strips to concrete surface is presented. The proposed model in this research has been validated using experimental results available in the literature. The results indicated that the proposed configuration of CFRP strips significantly improved the lateral resistance and deformation capacity of the shear walls with opening.

• Structural Engineering and Mechanics
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• v.27 no.4
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• pp.501-521
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• 2007

This study presents a model to better understand the shear behavior of reinforced concrete walls subjected to lateral load. The scope of the study is limited to squat walls with height to length ratios not exceeding two, deformed in a double-curvature shape. This study is based on limited knowledge of the shear behavior of low-rise shear walls subjected to double-curvature bending. In this study, the wall ultimate strength is defined as the smaller of flexural and shear strengths. The flexural strength is calculated using a strength-of-material analysis, and the shear strength is predicted according to the softened strut-and-tie model. The corresponding lateral deflection of the walls is estimated by superposition of its flexibility sources of bending, shear and slip. The calculated results of the proposed procedure correlate reasonably well with previously reported experimental results.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.76-79
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• 2004

The use of recycled aggregate concrete is increasing faster than the development of appropriate design recommendations. This paper is making advances in the recycling of waste concrete material for use as recycled aggregate to make secondary concrete product. Using recycled aggregates from demolished concrete, we manufactured concrete blocks to experiment overall performance in feasible performances. This paper reports limited experimental data on the structural performance of shear wall used concrete blocks made in recycled aggregates. Reinforced concrete frame and shear walls were tested to determine their diagonal cracking and ultimate shear behavior. The variable in the test program was the existence of infilled wall used concrete blocks Made in recycled aggregates. Based on the experimental results, Infilled wall has a high influence on the maximum strength and initial stiffness of reinforced concrete frame. Structural performance of specimen WSB1 and WSB2 is quite different from RCF specimen, particularly strength, stiffness and energy dissipation capacity.

• Steel and Composite Structures
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• v.52 no.2
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• pp.217-236
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• 2024

The objective of this paper was to discuss the seismic performance of hybrid FRP-steel reinforced concrete shear wall with replaceable friction dampers at the feet of the wall. The hysteretic characteristics of five wall specimens were studied by pseudo-static loading tests. The results showed that the damage of the specimens was concentrated on the friction dampers, and the energy consumption capacity was increased while making up for the defect of low ductility of FRP reinforced wall specimens. And the repairability of the wall after earthquake was improved. Finally, a calculation method of initial stiffness of shear wall with replaceable dampers was proposed.

• Journal of the Korea Concrete Institute
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• v.27 no.5
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• pp.489-499
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• 2015

This study suggested shear strength prediction model for retrofitted single-layered RC squat wall by providing column element as additional boundary element. This model revised existing shear strength prediction model of shear wall to consider detail and shear deformation capacity of column by assuming the length that concentrated shear deformation of the column is occurred. It was able to suggest additional compatibility condition related to shear strain of retrofitted of retrofitted shear wall at the ultimate state by using this length. Therefore, this study proposed a flow chart for predicting shear strength of the retrofitted shear wall considering this additional condition. Moreover, this study also proposed a method for predicting initial stiffness of the retrofitted shear wall by transforming the wall's resisting mechanism against to lateral load to a single diagonal strut mechanism. The proposed methods can predict shear strength and initial stiffness of not only the retrofitted shear wall of this study, also infilled RC shear wall in RC frame.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.756-765
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• 2015

Background: Fibers have been used in cement mixture to improve its toughness, ductility, and tensile strength, and to enhance the cracking and deformation characteristics of concrete structural members. The addition of fibers into conventional reinforced concrete can enhance the structural and functional performances of safety-related concrete structures in nuclear power plants. Methods: The effects of steel and polyamide fibers on the shear resisting capacity of a prestressed concrete containment vessel (PCCV) were investigated in this study. For a comparative evaluation between the shear performances of structural walls constructed with conventional concrete, steel fiber reinforced concrete, and polyamide fiber reinforced concrete, cyclic tests for wall specimens were conducted and hysteretic models were derived. Results: The shear resisting capacity of a PCCV constructed with fiber reinforced concrete can be improved considerably. When steel fiber reinforced concrete contains hooked steel fibers in a volume fraction of 1.0%, the maximum lateral displacement of a PCCV can be improved by > 50%, in comparison with that of a conventional PCCV. When polyamide fiber reinforced concrete contains polyamide fibers in a volume fraction of 1.5%, the maximum lateral displacement of a PCCV can be enhanced by ~40%. In particular, the energy dissipation capacity in a fiber reinforced PCCV can be enhanced by > 200%. Conclusion: The addition of fibers into conventional concrete increases the ductility and energy dissipation of wall structures significantly. Fibers can be effectively used to improve the structural performance of a PCCV subjected to strong ground motions. Steel fibers are more effective in enhancing the shear performance of a PCCV than polyamide fibers.

• Computational Structural Engineering : An International Journal
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• v.1 no.2
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• pp.117-130
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• 2001

Investigations of low-rice unbounded reinforced concrete shear walls with or without openings are performed with comparison of analytical and experimental results. Theoretical analysis is based on nonlinear finite element algorithm, which incorporates concrete failure criterion and nonlinear constitutive relationships. Studios focus on the effects of height-to-length ratio of shear walls, opening ratio, horizontal and vertical reinforcement radios, and diagonal reinforcement. Analytical solutions conform well with experimental results. Equations for cracking, yielding and ultimate loads with corresponding lateral displacements are derived by regression using analytical results and experimental data. Also, failure modes of low-rise unbounded shear walls are theoretically investigated. An explanation of change in failure mode is ascertained by comparing analytical results and ACI code equations. Shear-flexural failure can be obtained with additional flexural reinforcement to increase a wall's capacity. This concept leads to a design method of reducing flexural reinforcement in low-rise bounded solid shear wall's. Avoidance of shear failure as well as less reinforcement congestion leer these walls is expected.

• 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.