后张预应力预制混凝土框架节点抗震性能数值模拟与理论分析

为了研究由后张预应力筋将预制梁柱拼装在一起形成的框架结构的抗震性能，在四榀梁柱中节点低周反复加载试验的基础上，采用弹塑性分析程序DRAIN-2DX进行了数值模拟分析，并根据截面的受力平衡条件，给出了试件力-位移关系曲线上的几个关键点——开裂点、线性极限点、屈服点和承载力极限点对应的梁端弯矩值的简化计算公式。研究结果表明：通过合理建模和选择模型参数，采用DRAIN-2DX程序可以较为准确地模拟出试件整个试验过程中的楼层剪力-层间位移角关系滞回曲线和骨架曲线，曲线上的几个关键点也与试验结果吻合较好，但计算曲线的初始刚度偏大；简化计算公式具有一定的精度，便于工程设计应用。

NUMERICAL AND THEORETICAL ANALYSIS ON SEISMIC PERFORMANCE OF POST-TENSIONED PRESTRESSED CONCRETE BEAM-COLUMN ASSEMBLAGES

To evaluate the seismic performance of the concrete frame in which precast beams and columns are connected by post-tensioned tendons, numerical analysis of four beam-to-column assemblages which were tested under cyclic reversal loads was carried out using the software DRAIN-2DX. Then the simplified calculation formula of the beam end bending moment at several key points on the force-drift relation curve (including the cracking point, the linear limit point, the yielding point and the ultimate limit point) is derived based on principle of statically balancing. The analysis results indicate that the calculated shear force-drift hysteretic loops and the envelope curve agrees well with the experimental results, and the key points on the envelope curve are close to the experimental ones, while the analytical initial stiffness is relatively higher; the formula is proved to be effective and convenient for engineering application.