混凝土等效断裂韧度的虚拟裂缝模型解析方法

建立了一种求解基于虚拟裂缝模型的混凝土等效断裂韧度的实用解析方法.首先将虚拟裂缝区粘聚力作为相应的边界条件,运用修正的剪滞理论,根据能量法则推导出一种求解混凝土等效断裂韧度的解析计算模式;最后对照相关试验数据,得到了对应数值解的解析解,且与相关试验对应的数值解相比,解析解的均方差和变异系数更小,具有更好的鲁棒性.由此可以得出结论,所提出的解析计算模式为求解混凝土等效断裂韧度提供了一种可靠的实用解析方法.

Analytical method of equivalent fracture toughness of concrete based on fictitious crack model

Taking the cohesive force on the fictitious crack as the corresponding boundary condition,the variant layers in the shear lag model were introduced using the modified shear lag theory.An analytical model for solving the equivalent fracture toughness was deduced based on the energy principle.In order to check the test data of the coherent experiment,some analytical solutions were obtained corresponding to the numerical solutions.The calculated results show that the analytical solutions in this paper are more robust than the numerical solutions based on the coherent experiment.It can be concluded that the analytical model proposed provides a reliable practical analytical method to solve the equivalent fracture toughness of concrete.