Analysis And Research On Progressive Collapse Of RC Frame Structure

This paper analyses the mechanism of collapse of structure on the basis of learning and summarizing the research of scholars both at home and abroad.Failure criteria of stuctures have five categories, but in these criteria, strength criterion and deformation criterion are used most in analyzing structure.The collapse of general RC frame structure has eperienced three stages three stages:eastic stage, plastic stage, cable suspension stage; If we want to comprehensively understand the process, we still need to consider the dynamic effect in the process of collapse, the impact of collapse, and the contact and collision between components.This paper refers to design codes on resisting progressive collapse of many countries, especially the DOD2005 code of United States Department of Defense and the GSA2003 code of U.S.General Service Administration. Based on linear static analysis and linear dynamic analysis,the paper adopts SAP2000 analysis software to analyse a eight layer RC frame structure according to the current code of China on resisting progressive collapse. Standard of judgment is:if DCR>2, progressive collapse of structures will occur. One column will be removed respectively in 4 typical positon of the first floor when analyzing the structure,and the sequence is defined as follows:â‘ remove column C1 in the centre of short side directionâ‘¡remove column A5 in the centre of long side directionâ‘¢remove corner column Alâ‘£remove one column inside the structureResults of the analysis show that DCR of linear dynamic analysis is larger than that of linear static analysis, and progressive collapse will occur on linear dynamic analysis under these four kinds of conditions.Based on linear dynamic analysis, the largest DCR appears when the corner column A1 is removed, therefore the corner column will be in the most disadvantageous position when encountering impact load or explosion load.