Experimental Study On The Dynamic Compressive Damage Of Concrete

Concrete is widely applied in china,including architecture,bridge,mnnicipal works, transport,hydraulic projects,river port,underground works,mining, airport etc,for example nuclear power station,large dam,offshore platform,high television tower,multilayer structure and so on.The safety and normal operation of the structure are not only a pure technical and economic problem,but a big social problem concerning people's life,property and social stability.But these structures are usually large and complex,hold big and variable load,and must bear several kinds of atrocious environment and occasional accident,for example strong earthquake,crash of airplane,sudden high temperature (fire),impact of explosion and repeated assault of wind wave etc.so it is necessary to have a further study on dynamic and damage property of concrete under dynamic pressing load.This paper has a one-way stress dynamic pressing test on concrete,reference to the performance of concrete response under earthquake load,systematically studied the impacts of strain velocity on concrete intensity and deformation performance,the deformation law of intensity,modulus of elasticity and critical strain on different stain velocities,obtained the formula which can describe compressive resistance intensity changing of concrete under different strain velocities.It also studied the impact of load history on concrete dynamic performance and damage, analyzed impact of different initial dynamic load on concrete dynamic compressive resistance intensity and deformation performance,studied the evolution law of concrete damage on stress- strain space after holding different-size history loads under different strain velocities.The paper studied the concrete mechanical performance under biaxial stress state. The test divides into two parts, one is biaxial dynamic equal ratio load under different strain velocities,the other is biaxial dynamic pressing test after holding cyclic load history.It also studied impact of cyclic load history on concrete compressive resistance intensity, modulus of elasticity and critical strain and concrete dynamic damage evolution law after holding cyclic load history loads.