一种用于墙梁连接计算与分析的改进型膜单元

An Improved Membrane Element for the Calculation of Wall-beam Connection

带有转角自由度的膜单元应用于墙梁连接的数值分析时,由于转角自由度与位移场之间的关系并不如梁或板单元中的明确,容易导致分析结果与实际情况相比偏弱。通过罚函数法,将独立插值的转角位移场与协调位移场变形梯度的反对称部分建立约束关系,改进了基于ALLMAN型带转角自由度膜单元。将改进型膜单元植入ANSYS的标准分析模块,以一弧形墙为例对单元的各种性能进行测试。测试结果表明,改进型膜单元能够通过小片检验,无多余零能模式。以一双肢剪力墙结构为例进行数值对比计算,用以验证改进型膜单元在墙梁连接性能分析中的精确度。计算结果显示,改进型膜单元具有数据准备简单、编程方便,对罚参数不敏感等优点,是一种可靠的、性能优越的单元类型。

When a membrane element with rotation degrees of freedom is used for analyzing the wall-beam connection,some inferior analysis results are often produced because the relationship between rotation degrees of freedom and displacement field is not clear compared with beam or slab element. In this paper,the constraint relationship is established between the rotation displacement field with independent interpolation and the antisymmetrical part used for coordinating the deformation gradient of displacement field by adopting the penalty function method. An improved membrane element with rotation degrees of freedom is constructed based on ALLMAN. The improved membrane element is implanted in the standard analysis module of ANSYS,and then,a curved wall is adopted to test its single performance. Test results show that the improved membrane element can pass most of patch tests with no extra zero energy mode than the previous method. A coupled shear-wall structure is adopted to verify the overall performances of the improved membrane element used for analyzing the wall-beam connection. The calculation results show that the improved membrane element is a reliable and superior element,and has some advantages including simple data preparation,convenient programming,and insensitive penalty parameter.