高轴压比装配整体式预应力混凝土框架中节点抗震性能试验研究

装配整体式预应力混凝土框架中节点由预制柱、预应力T形叠合梁和现浇节点核心区组成，其中，预应力T形叠合梁采用穿过节点核心区的后张预应力筋（全黏结和部分黏结）。对2个高轴压比（0.68）装配整体式预应力混凝土框架中节点和1个现浇对比中节点足尺模型进行了低周反复荷载试验。试验结果表明：试件均发生梁端弯曲破坏，柱纵筋和核心区箍筋未屈服；试件滞回曲线均较饱满，表现出较好的耗能能力；3个试件的刚度退化规律基本一致，残余变形较小，变形恢复能力良好；与现浇对比中节点试件和全黏结预应力中节点试件相比，部分黏结预应力中节点试件的承载力分别高6%和1.5%，位移延性系数分别高11.8%和17.6%。

Experimental studies on seismic performance of monolithic precast prestressed concrete frame interior connections under high axial compression ratio

Monolithic precast prestressed concrete frame interior connection is composed of precast column, prestressed T-shaped composite beam, and cast-in-place (CIP) joint core region, where in the prestressed T-shaped composite beam is connected with fully or partially bonded post-tensioned tendons through the joint core region. An experimental study on reversed cyclic loading responses of three full-scale specimens under high axial compression ratio 0.68 in the column is presented, including two monolithic precast prestressed concrete frame interior connections with partially or fully bonded tendons, and one CIP control interior connection with partially bonded tendons. The results revealed that the damage mainly concentrated on beam end at the column face owing to flexural action, while longitudinal bars in the column and stirrups in the core region remained elastic; specimens exhibited stable and full hysteretic loops, good energy dissipation capacity and consistent stiffness degradation rule; the residual deformation of specimens was small, and specimens exhibited excellent deformation restoring capacity; compared with the CIP control specimen and the monolithic precast specimen with fully bonded tendons, the load-carrying capacity of monolithic precast specimen with partially bonded tendons was 6% and 1.5% higher, and the ductility coefficient was 11.8% and 17.6% higher, respectively.