Development of A Program for Inelastic Earthquake Response Analysis of 3-D RC Frame Structures

本文第一部分介绍了基于应力-应变的钢筋混凝土框架结构考虑三维组合应力影响的弹塑性地震反应分析的概念。采用基于滞回应力应变关系的纤维模型对钢筋混凝土构件的材料非线性进行了评价。通过对混凝土和钢的弹塑性弯矩-曲率关系的比较，检验了混凝土和钢的本构关系的准确性。通过对动力方程的逐步数值求解，计算了结构的非线性地震反应。利用本文的分析方法，可以对斜拉PC梁桥RC塔结构的弹塑性抗震性能进行详细的分析，表明轴力的动态变化是评价结构抗震安全性的一个重要因素。本文第二部分介绍了基于子结构的在线混合试验在非线性…计算中的应用整体结构的地震反应较大。对结构在非线性范围内表现强烈的部分进行了试验测试，以确定其恢复力特性，而结构的其余部分则解析地包含在模型中。对一系列钢筋混凝土多层剪力建筑框架进行了地震反应分析，通过在线试验直接测量了第一层的恢复力特性。试验结果表明，对于上部结构相对刚性的框架，较强的地震地震动在第一层截面引起了显著的非线性，进而影响了整体结构的整体响应计算。本文还包括了考虑轴力效应的修复钢筋混凝土构件的混合试验结果以及1989年10月17日美国洛马普里塔地震对混凝土桥梁破坏的调查总结。较少

The first part of this paper introduces the concept of stress-strain based inelastic earthquake response analysis of RC frame structures considering the effects of three dimensional combined stresses. The material non-linearity of RC elements is evaluated by using a fiber model based on hysteretic stress-strain relations. The accuracy of concrete and steel constitutive laws are examined by the comparison of analytical and experimental inelastic moment-curvature relations. Non-linear earthquake structural response is computed by numerical step-by-step solution of the dynamic equation of motion. By the present analytical method, the inelastic seismic behavior of RC tower structures of cable-stayed PC girder bridges can be examined in detail and it was shown that dynamically varying axial forces are an important factor to evaluate the seismic safety of the structure.The second part of this paper presents an application of substructure-based on-line hybrid tests for computation of inelasti … More c earthquake response of integral structures. The part of a structure expected to behave strongly in nonlinear range is experimentally tested to determine its restoring-force characteristic, while the remaining part of the structure is included in the model analytically. A series of reinforced concrete (R/C) multistory shear building frames were analyzed for earthquake response in which the first story restoring-force characteristics were measured directly from on-line experimental tests. Experimental results show that relatively strong earthquake ground motion induced significant nonlinearity in the first-story sections for these frames with relatively stiff upper stories, which in turn affected the overall response computed for the integral structures.The results of hybrid experiments on repaired RC members with axial force effects and a summary of the investigation on damage of concrete bridges due to Loma Prieta Earthquake of October 17, 1989 in the U. S. are also included in the report of this study. Less