提出一种预应力空间结构体系——弦支筒壳.采用基于响应面函数的蒙特卡罗法,运用APDL语言编制相应的计算程序;研究了弦支筒壳的稳定性及其整体屈曲失效模式下的可靠性;分析了矢跨比、垂跨比、撑杆数目和预应力作用等对结构承载力和变形失效模式下可靠性的影响,给出了基于结构可靠性的上述参数的合理取值.分析结果表明:弦支筒壳的屈曲特征值、非线性屈曲临界荷载值和整体稳定性的可靠度指标均比单层筒壳大幅度提高;矢跨比和垂跨比对结构可靠度的影响较大,而撑杆数目对其影响较小;预应力值的改变对结构承载力失效和变形失效的影响较大,而对整体屈曲失效的影响较小.
A prestressed spatial structure system, namely cable supported barrel vault, was put forward. By adopting the Monte Carlo method based on the response surface function, a program was written in APDL language to study the stability of cable supported barrel vault and its reliability in integral buckling failure mode. Moreover, the effects of rise-span ratio, sag-span ratio, number of shruts and prestressing force on reliable performance in strength and displacement failure modes were discussed. The optimal values of rise-span ratio, sag-span ratio and number of struts were obtained. The research results indicate that, compared with the single-layer cylindrical latticed shell, cable supported barrel vault structure shows obviously improved stability and reliability. Structure reliability is sensitive to rise-span ratio and sag-span ratio, but not to number of struts. The strength and displacement failure mode is sensitive to prestressing force, but the integral buckling failure mode is not.