Seismic Behavior Of Seismic-damaged Steel Reinforced Concrete Columns Strengthened With Steel Angles And Strips

Recently,with earthquakes happened more frequently in China,lots of buildings has been destroyed to different degree.Compared with rebuilding these buildings.Among these buildings,the main structure mode is Steel Reinforced Concrete buildings.Obviously,it's more efficiency and cost-effective to restore and strengthen them.This paper discuss mainly the performance of earthquake-damaged SRC(Steel Reinforcement Concrete)columns after being restored and strengthened with external steel and strips under cyclic load.Mechanisms involved in the behavior of the strengthened SRC columns has been analysed.The hysteresis modal of SSRC(Strengthened SRC)columns has been proposed.Results are as follow: Compared with the contrast specimen,the performance of the strengthened ones perform better in many aspects.The loading capacity of the strengthened ones get a sharp increasement,to 27% at most,;and the ductility factor of the strengthened ones,to 17% at most.The energy dissipation coefficient increase in small degree.After being strengthened,the restriction of the deformation on the concrete in the lateral direction provided by the steel caging generates a triaxial state of compression on the column,which increases the compression strength of concrete.The space of the steel strips at the end of columns should be closer.The steel angles should be added between the end of columns and base-beam.It's more effective and cost-well that gets clear analysis to the reinforcing effect.The reinforcing effect is divided into three parts:the increase of the core concrete compression strength,the friction effect,and the directly loading capacity of steel jacket.The proportion of reinforcement effect is 1:1.53:10.80.Under limited time and personal stamina,it's hard to give mature consideration to all aspects of the question.This paper has its own weakness.In the course of the experiment,the size of the steel angle,the space between strips,and the transfer member aren't considered.The impact of the friction between steel angles and concrete on the reinforcing effect doesn't get enough attention.Before the experiment,the finite element simulation analysis doesn't get considered.Though this paper proposes a kind of reforcing model,and gives the numerical numbers of the pivot point,this model get no at no consideration of the slippage in the process of reloading.The results above has some reference values to the performance of the earthquake-damaged SRC columns after being restored and strengthened with steel angles and strips,;and can provided the Strengthened design of damaged SRC columns with some reference.