中文摘要：

为了避免传统裂缝扩展模型中断裂韧度KIC的尺寸效应和定步长方法对模拟裂纹扩展过程的影响,针对混凝土宏观裂缝的应变尺度,提出＂最大周向拉应变＂裂纹扩展判据。结合混凝土的压碎破坏准则,建立混凝土＂拉-压＂组合破坏模型,并对三点弯曲简支粱的破坏过程进行模拟。

英文摘要：

In order to avoid the influence of simulating the crack propagation which cause by the scale dependency of fracture toughness（KIC） and the variable step method of the traditional crack propagation model,visible crack of concrete＇s strain measure is aim at,The crack propagation criterion of ＂Maximum circumferential tensile strain＂put forward.Combine the crush destroy model of concrete to build the ＂pull-crush＂ combinative destroy model of concrete,and simulate the destroy process of 3-point bending freely supported beam.