摘要
提出应用离散元法(DEM)来求解二维、三维杆系结构的几何非线性大变形问题.基于简单梁理论,推导了适用于杆系结构分析的弹簧接触刚度系数计算公式,给出了时间步长临界值估算方法,并用实例对其进行了正确性检验.DEM方法本质上是求解结构的动力行为,对于需要计算静力解的问题,综合考虑数值精度和计算效率,建议阻尼系数取为0.7.列出了3个典型数值算例,即2个平面框架和1个空间网格结构,分别对其静力和动力大变形行为进行了模拟,并将结果与其他计算方法的结果进行比较,两者吻合良好.利用DEM方法处理几何非线性问题时无需组集刚度矩阵,也无需迭代求解非线性方程,故该方法适宜于处理杆系结构的大变形问题.
The discrete element method （DEM） was applied in geometric nonlinear analysis with large deformation of member structures including two-dimension and three-dimension frames. Based on the simple beam theory, the spring contact stiffness expression for analysis of member structures was derived. The estimation method of the critical value for the time step size was proposed, and the verification of numerical test was carried out. Since the DEM is essentially used to resolve dynamic problem of structures, for the problem of calculating the static solution, the proposed damping coefficient is taken as 0.7 considering the numerical accuracy and computational efficiency. Three classical numerical examples were presented, including two planar frames and a spatial reticulated structure. Their static and dynamic large deflection behaviours were simulated respectively. The calculation results agree well with the solutions by other numerical methods. Without assembling stiffness matrixes and iterations during structural geometric nonlinear analysis, the DEM is reliable in dealing with large deformation problem for member structures.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第5期917-922,共6页
Journal of Southeast University：Natural Science Edition
基金
国家杰出青年科学基金资助项目(51125031)
关键词
离散元法
杆系结构
弹簧接触刚度
几何非线性
静动力响应
discrete element method
member structure
spring contact stiffness
geometrical nonlinearity
static and dynamic response
