外置可更换软钢装配式桥墩力学性能研究

Study on Mechanical Properties of External Replaceable Soft Steel Assembled Bridge Piers

为了提高装配式桥墩承载力、减轻地震损伤,达到震后快速修复使用功能的目的,提出一种榫头承插式桥墩结构优化方法——外置可更换耗能软钢。分别建立现浇桥墩和外置可更换耗能软钢的榫头承插式桥墩非线性有限元模型,通过数值分析对比两种桥墩力学性能的差异。结果表明:外置可更换耗能软钢的榫头承插式桥墩的竖向承载力大于现浇桥墩;相较现浇桥墩,耗能软钢榫头承插式桥墩水平极限位移更大且承载力达到峰值后下降速度较慢;外置可更换耗能软钢的榫头承插式桥墩的滞回性能、水平等效刚度、延性、残余位移和耗能能力与整体现浇桥墩基本一致。

To improve the bearing capacity of assembled piers,reduce earthquake damage,and achieve the purpose of quick repair after the earthquake,a structural optimization method of mortise and tenon socket piers was proposed,composed of external replaceable energy-consuming soft steel.A nonlinear finite element model was established for cast-in-place piers and mortise and tenon abutments with replaceable energy-consuming soft steel,and the differences in mechanical properties between the two types of piers were compared by numerical analysis.The results showed that the vertical bearing capacity of the mortise and tenon abutment with replaceable soft steel was larger than that of the cast-in-place abutment.The lateral ultimate displacement of the mortise and tenon abutment with replaceable soft steel was greater than that of cast-in-place abutment,and the bearing capacity decreased more slowly after the peak.The hysteresis performance,horizontal equivalent stiffness,ductility,residual displacement and energy dissipation capacity of the mortise and tenon abutment with replaceable soft steel were basically the same as those of the cast-in-place abutment.