基于分离式建模的砌体墙力学性能有限元分析参数探讨

Discussion on parameters in finite element analysis of mechanical properties of masonry wall based on separation modeling

基于ABAQUS接触分离式建模方法建立砌体墙的精细化模型,将砂浆与砖之间的粘性破坏限定在砂浆基质中间,并引入砖潜在缝以便观察砌块破坏,利用粘性接触界面来模拟砂浆和砌块开裂。通过相关文献和规范,根据实际对接触界面的刚度、强度、断裂能和摩擦系数等参数进行探讨,发现界面刚度公式具有适用范围,超过该范围需要调整;界面抗剪强度的规范公式也具有一定富余度,与实际试验有出入;通过刚度和强度可以确定断裂能的公式,从而确定合理的界面接触模型。根据该模型,对3片无筋砌体墙的拟静力抗剪试验进行仿真模拟,得出的裂缝开展情况和力-位移曲线与试验结果拟合较好,证明该模型可以有效反应砌体墙的剪压破坏,能够满足砌体精细化模拟需求。

The fine model of masonry wall was established based on ABAQUS contact separation modeling method.The viscous failure between mortar and brick was limited to the middle of mortar matrix.The potential crack of brick was introduced to observe the block failure.Viscous contact surfaces were used to simulate mortar and block cracking.Based on the relevant literature and specifications,the parameters such as the stiffness,strength,fracture energy and friction coefficient of the contact interface were discussed according to the actual situation.It is found that the interface stiffness formula has an applicable range,beyond which it needs to be adjusted.The standard formula of interfacial shear strength also has a certain degree of redundancy,which is different from the actual test.The formula of fracture energy can be determined by stiffness and strength.According to this model,the pseudo-static shear tests of three non-stiffened masonry walls were simulated.The obtained crack development and force-displacement curves fit well with the test results,which proved that this model could effectively reflect the shear stress failure of masonry wall and meet the demand of masonry fine simulation.