预应力混凝土框架边节点抗震性能试验

预应力混凝土框架结构在地震作用下的反应与普通钢筋混凝土结构相比存在着差异,且受力复杂,难以通过理论分析得到其抗震性能.结合实际工程,通过框架节点试验模型在低周反复加载作用下的拟静力试验,研究了后张有粘结预应力混凝土框架边节点的破坏形态、滞回特性、骨架曲线、刚度退化、破坏时应变等.研究结果表明:水平地震作用下有粘结预应力混凝土框架边节点模型的位移滞回曲线由梭形变化到反S形,存在捏拢现象;位移延性系数能达到4.0以上,耗能能力较强,结构具有较好的抗震性能;建议通过加大柱截面和增强柱端抗剪钢筋来实现强剪弱弯.

Experimental study of aseismic performance of bonded prestressed concrete exterior joint

Compared to reinforced concrete structures, the seismic response of prestressed concrete structures is more complicated and the seismic performance could hardly be obtained by theoretical analysis.Based on a practical engineering, an experimental study is conducted on aseismic performance of post-tensioned bonded concrete exterior joint with strong beam-weak column subjected to reversed cyclic load. The failure pattern, hysteresis properties, skeleton curve, stiffness deterioration and failure strain etc. of the prestressed joint are studied. The results indicate that the displacement hysteretic loops of the bonded prestressed concrete frame exterior joint under the horizontal earthquake vary from shuttle to reversed-s shape with pinch; the ductility factor of this type of structures is larger than 4.0; and the dissipative capability is moderate. The aseismic performance of the prestressed exterior joint is satisfactory. It is advised that the column sectional area be enlarged and the shear reinforcement of column ends be augmented to realize the flexural failure instead of the shear failure.