混凝土受拉随机损伤本构关系及其应用

利用扩展的弹簧模型 ,从细观层次上分析了混凝土试件在单调拉力作用下的宏观性能 ,解释了混凝土单轴受拉应力 -应变关系中的应变软化和应力跌落现象 ;基于静力平衡和变形协调条件 ,建立受拉本构关系 ;利用单轴受拉试验 ,确定细观损伤单元的极限破坏应变随机场分布参数 ;与已有试验结果相比较 ,结果吻合较好

A STOCHASTIC DAMAGE CONSTITUTIONAL MODEL AND ITS APPLICATION TO UNIAXIAL TENSILE BEHAVIOR OF CONCRETE

The concrete materials damage, which has been caused by monotonic tensile loading, is analyzed from mesoscopic fracture. The nonlinear performance of the curve is analyzed using a class of mesoscopic springs model. The model can also explain the phenomena such as strain softening and stress drop. With the help of force equilibrium and deformation compatbility, a damage constitutional model of concrete under monotonic tensile loading is put forward. Based on the experiments on the concrete subjected to monotonic tensile loading, the coefficients can be uniquely determined. It is found that the calculated curve has a good agreement with experiment′s.