Experimental validation on seismic performance of a monolithic precast RC shear wall structure with novel connections

A novel monolithic precast concrete shear wall structure system was proposed, with four connector types: “cast-in-site elbow reinforced concrete joints,” “dry connectors,” “shaped steel shear keys,” and “shaped steel boundary elements” based on welding process with stable and high quality. The first two connect walls horizontally and the other two connect walls between adjacent stories. A high precast ratio, over 60%, can be achieved. To evaluate the strength, stiffness, ductility, and energy dissipation capacity of the proposed system, a full-scale three-story model was tested quasi-statically in the two horizontal directions. The model showed strong spatial response, demonstrating sufficient strength and stiffness to resist severe earthquakes. The coupling beams suffered shear failure damage. The connectors sustained large internal forces, surviving under simulated severe earthquake conditions. The external thermal insulation layers remained firmly attached to the precast wall panels, satisfying the design objectives.

On the Behavior of Coupled Shear Walls: Numerical Assessment of Reinforced Concrete Coupling Beam Parameters

Modern construction of high-rise and tall buildings depends on coupled shear walls system to resist the lateral loads induced by wind and earthquake hazards. The lateral behavior of this system depends on the structural behavior of its components including coupling beams and shear walls. Although many research studies in the literature investigated coupling beams and shear walls, these studies stopped short of investigating the coupled shear walls as a system. Therefore, in this research, the effect of the coupling beam parameters on the nonlinear behavior of the coupled shear walls system was investigated. The full behavior of a 10-story coupled shear wall system was modeled using a series of finite element analyses. The analysis comprised of testing several coupling beam parameters to capture the effect of each parameter on system response including load-deflection behavior, coupling ratio, crack pattern, and failure mechanism. The results indicated that a span-to-depth ratio equal to two is a turning point for the coupling beam behavior. Specifically, the behavior is dominated by ordinary flexure for a ratio of more than two and deep beam behavior for a ratio of less than two. This study showed that the coupling beam width does not have a significant effect on the coupled shear wall response. Additionally, it was concluded that the excessive coupling beam diagonal reinforcement could significantly affect the coupled shear walls behavior and therefore an upper limit for the diagonal reinforcement was provided. Moreover, limitations on the longitudinal and diagonal reinforcement and stirrups are presented herein. The analysis results presented in this paper can provide guidance for practitioners in terms of making decisions about the coupling ratio of the coupled shear walls.

Influence of coupling beams to the energy dissipation of coupled steel plate shear wall

Shear Plate Shear Wall (SPSW) is a lateral force resisting system that is usually used in high seismic regions. Opening can be accommodated by using coupled steel plate shear wall (CSPSW) where two or more SPSWs are placed adjacently and are connected by coupling beams. Maximum displacement, shear load capacity and energy dissipation are affected by the dimension of the coupling beams. The construction cost of the building can be reduced vastly by optimizing the size of the coupling beams where the capability of CSPSW to resist the earthquake is maximized. Thus, the objective of this study is to determine the behaviour of maximum displacement, shear load capacity and energy dissipation of the CSPSW when the width, depth and length of the coupling beams are varied. Fourteen CSPSW models were analysed by ABAQUS software, where the models were subjected to lateral cyclic loading as accordance to ATC24. Maximum displacement of the CSPSW was not affected by the dimensions of the coupling beams. Shear load capacity was increased as either the width or the depth of the coupling beam was increased, and achieved its maximum value when the length of the coupling beam was 1000 mm. The optimum width, depth and length of the coupling beam to maximize the energy dissipation of the CSPSW models were 200 mm, 1000 mm and 1000 mm, respectively.