混凝土三维细观接触面模型数值模拟与CT试验验证

对混凝土三维随机骨料模型进行了改进,在骨料和砂浆之间加入了"面-面接触单元"模拟两者的接触特性,编制了相应的命令程序,称新模型为混凝土接触面模型.采用双折线损伤演化模型进行计算,对数值模拟结果进行了分析研究.从混凝土破坏过程图和荷载-位移曲线图两方面与CT试验结果进行了比较,表明试件破坏时裂纹的萌生、扩展过程与CT试验...

Numerical simulation on 3D meso-contact mesh of concrete and CT test verification

The contact mesh model is used to improve 3-D model of random aggregate concrete. Contact mesh is used for simulating interface material between aggregate and motor, the corresponding calculation program is made. So the new model is called contact mesh model of concrete. The conduplicate-line damage evolvement model is applied, the computation results of numerical simulation are analyzed and researched. The results of numerical simulation and CT experiment are compared in failure charts of concrete and curve charts of load-displacement. The crack initiation and propagation are similar with the results of CT experiment; the curve chart of load-displacement of numerical computation is certain extent uniformity with real experiment results. Thereby the contact mesh model overcomes the shortages of random aggregate model, which are as follows: the great thickness of the interface, the great number of element, the slow calculation speed, and the wide hole-zone of crack so ,it is indicated that the improved numerical model of concrete can not only be more similar with the real model, but also greatly increase the speed of computation.