ANALYSIS OF HYSTERETIC BEHAVIOR FOR UNBONDED STEEL PLATES OR STEEL BARS INSTALLED BETWEEN THE UPPER AND LOWER CONCRETE SHEAR WALLS

摘要

In order to adjust the lateral stiffness of concrete shear walls and improve the lateral deformation capacity of concrete shear walls, a novel shear wall made up of an upper concrete panel, a lower concrete panel and the steel bars (or steel plates) is introduced. The steel bars (or steel plates) are embedded in the upper panel directly and embedded in the lower panel after embedded portions of steel bars (or steel plates) are coated with the unbonded material. The numerical simulation was carried out to investigate working behavior of the shear walls and to examine the effects of constructional details on hysteretic behavior of the shear walls. The analysis results real that the steel plates, as well as steel bars, punch shear the holes in the lower panel and therefore cracks around the holes in lower panels occur severely when large relative horizontal displacement between the upper panel and the lower panel takes place. The extent of the cracks can be relieved greatly when the reinforcement that is a steel plate welded with interval steel plate ribs is installed on the top surface of the lower panels, and the shear walls with the reinforcement exhibit stable hysteretic behavior even after large yielding development in the steel bars (or steel plates). When without this reinforcement, the cracks of lower panels are more severe. Besides, the cracks and brittle tensile failure of concrete shear walls around the connecting plates show that further reinforcements are required. The lateral stiffness and resistance of shear walls can be easily adjusted, and it is convenient to the design and application of shear walls.