【摘要】 利用改装的杆径为 74mm的直锥变截面式大尺寸Hopkinson压杆对混凝土材料进行冲击压缩实验 ,系统研究了混凝土的应变率硬化效应 ,采用一种新的方法———“损伤冻结”法对混凝土材料在冲击载荷下的损伤软化效应进行了系统研究 ,给出了冲击载荷下混凝土的损伤演化方程 ;在对数据进行合理分析的基础上 ,结合粘弹性本构理论 ,得到混凝土材料的损伤型线性粘弹性本构关系更多还原

【Abstract】 Constitutive properties of concrete under dynamic loading play an important role in the analysis of concrete structures subject to impact loading.There are many defects such as micro crack and micro void inside the concrete material.Damage softening has a great influence on the mechanic behavior of concrete under impact.So a new experiment method called "freezing in "damage test is used to obtain the damage evolution equation.The impact compression tests are performed with a modified right cone 74 mm diameter SHPB.The results of experiments show both strain rate stiffening effects and the damage softening effects.Based on ZWT visco elasticity model a linear visco elasticity according to damage evolution constitutive relation of concrete is obtained.更多还原