交叉立体桁架系巨型网格结构的超级元与子结构相结合计算法
THE METHOD OF COMBINING SUPER FINITE ELEMENTS AND SUBSTRUCTURES FOR ANALYSIS OF LATTICE-INTERSECTED THREE-DIMENSIONAL RETICULATED MEGA-STRUCTURES
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摘要: 针对交叉立体桁架系巨型网格结构杆件、节点多、计算工作量大的特点,提出了超级有限元与子结构相结合的简化求解方法:采用三节点立体桁架超级元来处理主体结构中的立体桁架,用子结构法来处理大网格内的子结构.推导了超级元刚度矩阵及子结构参与协同承载时对整体结构的刚度贡献.经编程对比计算分析表明,该法计算精度高,误差基本保持在5%以内,计算工作量较完全有限元法明显降低,且可考虑子结构的参与协同承载,是分析巨型网格结构的一种比较优越的方法.Abstract: In this paper, a simplified analysis method of combining super finite elements and substructures is presented and studied for reticulated mega-structure in which the main-structure is lattice-intersected three-dimensional system. To reduce the calculation time, the main-structure is discretized using super element of three nodes and substructures of large grids. The super element stiffness matrix and the stiffness contribution of substructures to the whole structure are developed. It is shown that the calculating time of the present method is reduced significantly in comparison with complete finite element analysis and accurate results are obtained. The present method can also consider the load-bearing contribution of the sub-structures. It is a superior analysis method for the reticulated mega-structures.