交叉立体桁架系巨型网格结构的简化计算法

针对系巨型网格结构杆件和节点多、计算工作量大的特点,进行了简化计算方面的研究,提出了将立体桁架等效为连续实体梁、按空间法进行有限元计算的等效空间刚架法.分析了立体桁架的等效截面、等效抗弯刚度,并详细推导了其等效抗扭刚度,分析了主体结构不同边界条件的等效处理方法.对比计算分析表明,该方法计算精度高,主要受力杆件的误差保持在5%以内,计算工作量较完全有限元法大幅度降低,是分析巨型网格结构的一种比较优越的方法.

Simplified Analysis Method of Latticed Intersected Three-Dimensional Beam System Reticulated Mega-Structure

A simplified analysis method was studied for reticulated mega-structure in which the main-structure was latticed intersected three-dimensional beam system(LITDBS) because of the long calculating time caused by its large amount of elements and nodes.The equivalent space frame method,which considered latticed three-dimensional beam as a continuous solid three-dimensional beam and used finite element method(FEM) to analyze it,was presented.The equivalent section area and the equivalent flexural stiffness were analyzed.The equivalent tensional stiffness was deduced in detail.The equivalent disposal method of different restrict conditions of the main-structure were analyzed.It showed that the calculating time of this method was much shorter than the full FEM',its accuracy was very high by comparative analysis,and the percentages of the error of the internal forces in the main bearing elements were all kept within 5%.So it is a superior analysis method for LITDBS reticulated mega-structure.