钢筋混凝土框架结构全过程pushover分析

以往采用杆系模型对钢筋混凝土结构进行pushover分析时，杆端塑性铰所采用的力一变形关系模型中特征参数的计算是基于杆件的原始尺寸，且对变形的极限值(如极限曲率)没有加以限制，这种本构模型并不能完整地体现构件的受力全过程。本文首先采用数值计算方法分析了钢筋混凝土压弯构件保护层混凝土剥落后强度的变化以及箍筋约束作用对其强度和延性的影响。在此基础上，以一个预应力混凝土框架结构为例进行了全过程pushover分析。算例分析结果表明，这种分析方法能够更合理地反映结构从加载到破坏的整个受力过程。

Complete pushover analysis of RC frame structures

In the traditional pushover analysis of RC structures, character parameters in the force-deformation relation of the plastic hinges are usually computed based on the initial dimensions of the members, and limitation of deformation, such as the extreme curvature, is not defined. This constitutive relation is not able to represent the whole response process of the members exactly. In this research, numerical method was used to analyze the change in strength of members with flexures and axial force after spalling of cover concrete and effect of transverse reinforcement on their strength and ductility. Based on analysis above, complete pushover analysis of a PRC frame was operated. The result seems to indicate that this complete pushover analysis is more reasonable as it can reflect the whole process of the structure from initial loading to damage.