拉索对索-桁穹顶结构的敏感性影响分析

Sensitivity analysis of cable-truss dome structures

索-桁穹顶结构中拉索的施工是该种结构的难点和关键点.在实际施工中,拉索的初始预应力值往往难以与设计值完全一致,因此,研究拉索对索-桁穹顶结构的敏感性,指出具体拉索是否具有敏感性,对设计与施工均有指导意义.本文采用正交设计分析法,对索-桁穹顶结构中的拉索按L8建立正交表,分别研究了拉索对该种结构的静力、动力及稳定性的敏感程度.结果表明,外环索对结构的性能甚为敏感,内环索对结构的动应力较为敏感,而斜索对结构的稳定性十分敏感.

The construction of cables is the key point of cable-truss dome structures. During the actual construction process, the initial prestress of cables is hardly identical with the design value. The sensitivity analysis of cables is therefore significant for the design and construction. In this paper, orthogonal design method is adopted to establish orthogonal tables for contriving an analysis scheme, and the nonlinear static, dynamic and buckling analysis are carried out for identifying the sensitivity of the cables. The results show that outer hoop-cable is the most sensitive cable among all cables and inner hoop-cable is sensitive to dynamic stress and diagonal cable is sensitive to structural stability.