针对ANSYS在非线性力学分析过程中常出现的收敛困难问题,提出了可以考虑复合破坏形式的等效损伤单元模型。该模型采用较为简单的本构关系,并且结合混凝土结构的细观损伤演化机理,利用增量形式的动力非线性迭代算法提高非线性分析收敛性。以ANSYS的用户可编程特性(UPF)为二次开发工具,将模型嵌入ANSYS平台并且通过三维模型静动力分析验证嵌入的模型与标准ANSYS计算结果的误差在静力工况下为5%,在动力工况下为12.3%,在后处理时可以通过将完全损伤单元消除的方法来模拟动力作用下结构破坏过程。在实际应用中该模型的精度与可靠性可以满足需求同时能够清晰直观地显示结构薄弱部位。
Focusing on the issue that the convergence difficulty phenomenon appears frequently during the process of nonlinear mechanics analysis by ANSYS,an equivalent-damage element model which can give consideration to the composite damage was proposed. The model utilized simple constitutive relation and damage evolution model for concrete. Based on the dynamic nonlinear iteration technique in the form of increment which can improve the nonlinear convergence. Furthermore,User Programmable Feature( UPF) was exploited as the redevelopment tool in order to embed model in ANSYS. According to the analysis results,the error was less than 5% under the static condition and 12. 3% under the dynamic condition. Finally,the complete damage elements could be"unselected"in order to simulate the damage behavior of structure during post-processing. The accuracy and reliability of the algorithm can meet demand,meanwhile,the weakness part can be displayed visually.