The Research Of Reinforced Concrete Frame Structure's Damage Parameters And Damage Degree Under Earthquake Action

In recent years,structural damage in capacity design,seismic strengthening and seismic evaluation has been paid more and more attention.The structural damage will not only influence its performance and structure safety,even will suddenly collapse resulting in destruction,and different types of damage and damage degree will directly affect the determination of the reinforcement scheme.The research of the seismic reinforced concrete frame columns in damage is more,and for integral reinforced concrete frame damage research is relatively less.Combining with the Henan province key science and technology project(092102310036),the overall frame structure under the action of earthquake damage parameter and degree of injury were studied which were based on the reinforced concrete frame under the action of earthquake simulation test and finite element analysis,mainly in research as follows:Based on the research of reinforced concrete frame structure in horizontal low cyclic loading experiment,the relationship between the relative stiffness and the relative load of the single layer and single span reinforced concrete in the stage of before cracking and cracking to yield phase has been reached,and on this basis i put forward the damage degree calculation model which takes the relative stiffness as damage parameter.The model is validated through the finite element analysis.Then,for the research of the reinforced concrete frame structure's damage degree during the stage of yield to failure,this paper mainly consider from two aspects which are large deformation amplitude and load cycle that will cause the frame structure's damage degree.So,in one hand,this paper take the plastic rate as damage parameter which can reflect the damage degree caused by the large deformation amplitude;in the other hand,the damage degree caused by load cycle is mainly reflected by the relative stiffness degradation which is taken as damage parameter.Combining with the test results,the damage degree's calculation model of the yield to failure stage has been deduced.This formula has good physical significance,and it has been verified through the finite element analysis.At last,on the basis of the single layer and single span reinforced concrete frame structure's research,this paper establish some two-layer and two-span reinforced concrete frame models with different height,span and section size by the finite element analysis software?Through the finite element analysis,we can get the conclusion that the previously discussed three damage models of single layer and single span reinforced concrete frame can also be used in two or more layers and two or multiple span reinforced concrete frame.It also proves that the proposed damage model has better universality and engineering application value.