万福磊，  李云贵
    （中国建筑科学研究院，北京 100013）

[摘要] 显式有限元可以不生成单元刚度矩阵，因而无法采用刚度矩阵计算刚度阻尼。参照隐式有限元刚度阻尼的生成方法，并考虑显式有限元的计算原理，研究了通过材料本构实现刚度阻尼的方法和程序计算流程；进而针对三维梁元研究了刚度阻尼系数对稳定时间步长的影响规律，确定了折减系数与阻尼系数和单元特征长度的对应关系。数值计算表明，刚度阻尼严重降低稳定时间步长，对于结构显式动力分析不建议采用刚度阻尼，在需要考虑阻尼影响时建议采用质量阻尼。
[关键字] 刚度阻尼；稳定时间步长；显式有限元；三维梁元
中图分类号：TU311.3  文献标识码：A  文章编号：1002-848X(2011) Sl-0256-04

Implementation of stiffness damp of explicit frnite element method and its influence to the stability time step length
    Wan Fulei, Li Yungui
    ( China Academy of Building Research,  Beijing 100013,  China)

Abstract: Due to the explicit finite element procedure needn't form the element stiffness matrix, the stiffness damp can not be determined by the stiffness matrix. Considering the implementation method of implicit finite element stiffness damp,a stress stiffness damp was realized in the explicit dynanuc analysis. The influence rule of stiffness damp to the stability time step was studied through a three dimensional beam dynamic analysis. The numerical result shows that the stiffness coefficient will reduce the stability time step length greatly. So the application of the stiffness damp coefficient is not suggested in the explicit dynamic analysis. The mass damp coefficient is suggested when the damp should be considered.
Keywords: stiffness damp; stability time step length; explicit firute element; three-dimensional beam element