Investigation On Seismic Performance Of Infilled Steel Plate-Concrete Shear Wall With Trapezoidal Shear Connectors

Composite shear wall has been widely implemented to high-rise buildings due to its distinct advantages in shear strength,lateral stiffness,deformation capability,ductility and energy dissipation capability.For building structures,the adaption of steel plate in wall component could effectively minimize the dimension of its section,reducing the adaption of floor area thus better achieving the building functions.Generally,composite shear wall refers to the infilled steel-plate shear wall and the concrete encased composite shear wall.While both two types of composite shear wall are adapted to a wide range of construction projects,they bear disadvantages of excessive consumption for steel plate and over complex procedure for distributional bar connection due to section characteristics.The current manufacturing process of prefabricated composite shear wall contains the process of welding studs on steel plate and binding steel meshes with extra positioning measures,however,a shear stud with adequate length could provide anchor point for steel meshes,thus,by integrating the shear stud and vertical distributional reinforcement into single component,the usage of tie bar as well as punching openings on infilled steel plate could be omitted,which could cause reduction on component strength.Based on the concept above,a novel type of infilled Steel plate-Concrete Composite shear Wall(SCCW)using trapezoidal reinforcement shear connectors was proposed.A cyclic loading test of 3 composite shear walls and 1 reinforced concrete shear wall(RW)was carried out to investigate the shear strength,deformation capability,lateral stiffness,ductility and energy dissipation capability of components.The parameters considered include the distribution mode of trapezoidal reinforcement shear connectors and the existence of horizontal distributional reinforcement.Test result shows that novel infilled Steel plate-Concrete Composite shear Wall with staggered distribution of shear connectors exhibited higher shear strength than parallel distribution,while the distribution mode has minor influence on the initial cracking and penetration displacement angle of components.The existence of horizontal reinforcement increases the overall value of performance parameters and confines the development of cracks and spalling of concrete into a lesser area.Shear strength,yielding displacement and ultimate displacement of composite shear wall specimens were higher than reinforced concrete shear wall specimen and the larger encircled area of hysteresis loops at the same displacement shows the higher energy dissipation capability of composite shear wall.Compared with reinforced concrete shear wall,the yielding displacement of specimens without horizontal reinforcement increased by 16.2%,while the ductility decreased by 1.5%;which is in contrast with specimens adopted horizontal reinforcement whose yielding displacement and ductility increased by 79.9%and 23.8%.The observation of specimens shows that the horizontal displacement could effectively constrain the development of cracks after yielding and improve the ductility of specimens and no obvious out-of-plane deformation was observed in the core area of specimens after test.In addition,some adjustments were adopted to the partial factor of the current design code based on test strength,and recommended design equation of infilled steel plate shear wall with trapezoidal reinforcement shear connectors was proposed.