Lateral Load-Displacement Response of Flexure-Dominant Concrete-Encased Steel Columns Based on Current Specification
Steel reinforced concrete(SRC)columns are widely used in high-rise structures due to their great load-carrying capacity,rigidity and durability.Currently,the seismic design of SRC members is based on the ultimate limit state,which cannot evaluate the seismic behavior according to different performance levels.As the most important element in displacement-based seismic design,the modeling of the lateral load-displacement curve of SRC members lacks a guidance provided by design standards.In this paper,a lateral load-displacement curve for flexure-dominant SRC columns under a nonlinear static procedure is proposed based on the provisions of RC members in the current ASCE/SEI 41-17.In the proposed curve,the sectional strength of the SRC member is calculated by using the confined concrete strength.The slip between the structural steel and surrounding concrete is considered by reduced lateral stiffness.Meanwhile,the end rotation caused by the bar slip in RC is also taken into account to simulate the lateral behavior better.Finally,the applicability of the proposed curve is proved by comparing to the experimental results of 28 SRC flexure-dominant columns.The results show that the proposed curve can have reasonable predictions on cracking load,cracking displacement,peak load,peak displacement and strength degradation of flexure-dominant SRC columns.Therefore,the curve can facilitate the performance-based seismic design of SRC structures.
万方数据
维普
