Schwedler网壳结构强震作用下的动力强度破坏研究

DYNAMIC STRENGTH FAILURE OF SCHWEDLER LATTICED SHELLS SUBJECTED TO STRONG GROUND MOTIONS

对Schwedler单层球面网壳结构进行了强震作用下的动力全过程分析,研究了结构的失效机理。对40m跨的Schwedler理想网壳结构和考虑初始缺陷的网壳结构进行了全过程动力时程分析,考查了此类型网壳结构的动力性能和破坏形式,采用一致缺陷模态法处理初始缺陷,分析了初始缺陷对Schwedler网壳结构动力性能的影响;对具有初始缺陷的网壳结构进行了参数影响分析,分别考查了地震作用、杆件截面和屋面荷载三种因素对结构动力性能的影响;将研究结果与其它球面网壳结构进行了比较,验证了文献[6]提出的理论框架的合理性和实用性。

The failure mechanism of single-layer spherical Schwedler latticed shell under strong ground motions was studied through dynamic time history analysis of the whole-process, with which a perfect and an initially imperfect latticed shell with 40m span were considered. The dynamic behavior and failure modes of this kind of latticed shells were investigated by these two typical examples. Also, the impact of initial defects on the dynamic behavior of single-layer spherical Schwedler latticed shell was analyzed. The so-called consistent imperfect mode method was applied to deal with such initial imperfectness. A parametric study was carried out to study the effects of three influencing factors, i.e. strong ground motion, sectional dimensions and roof live load, on the dynamic behavior of the imperfect shell. The comparison between the results from the two single-layer spherical Schwedler latticed shells and those from other spherical latticed shells validates the design philosophy suggested by Ref.[6].