基于损伤分布模型的震损RC框架力学性能分析与实证研究

震损结构的剩余荷载位移响应分析十分重要，是准确评估震后钢筋混凝土(RC)框架结构剩余性能的基础，然而震损结构损伤的不均匀分布为其荷载位移响应的定量分析带来了困难。本文基于纤维梁柱模型提出了一种能够考虑地震损伤不均匀分布的震损RC框架数值模型。基于震损RC框架的损伤现象对其损伤分布进行了量化，考虑了材料损伤沿柱高度与截面深度的分布；基于量化结果分别确定了RC框架中各纤维梁柱单元中不同位置处纤维的损伤本构关系，并对其剩余荷载位移响应进行了定量分析；以一个一榀三层四跨的RC框架试验为算例，对模型进行了验证。结果表明，本文模型能够较为准确地模拟震损RC框架的剩余荷载位移响应，其中最大剩余承载力、刚度和屈服强度等各项指标计算误差均值均在10%以下，因此本文模型能够为震后RC结构的评估工作提供一种新的思路。

Analysis and empirical study of mechanical properties of RC frames with seismic damage based on damage distribution model

Residual load-displacement response analysis of seismically damaged structures is important as a basis for accurate assessment of the residual performance of post-earthquake reinforced concrete (RC) frame structures.However,the inhomogeneous distribution of damage in the seismically damaged structure poses difficulties for the quantitative analysis of its load-displacement response.In this study,a numerical model of seismic damaged RC frame that can take into account the inhomogeneous distribution of a seismic damage is proposed based on the fiber beam-column model.The damage distribution is quantified based on the damage phenomena of the seismically damaged RC frame,and the distribution of damage along the column height and section depth is considered.Based on the quantitative results,the constitutive relationships of damage of the fibers at different locations in each fiber beam-column unit of the RC frame are determined separately,and the remaining load-displacement response is quantitatively analyzed based on these.Finally,test of an one-bay,three-story,four-span RC frame is used as a numerical example to validate the model.The results show that the proposed model can simulate the residual load-displacement response of the RC frame with the maximum residual load capacity,stiffness,yield strength and other indexes more accurately,with errors below than 10%,so the proposed model can provide a new tool for the evaluation of post-earthquake RC structures.