弦支组合网架结构可靠度分析

Reliability Analysis on Combined Grid String Branch Structure

根据张弦梁结构的思想提出由组合网架和索通过支杆相连而形成的预应力结构即弦支组合网架结构。建立一弦支组合网架结构的计算模型,利用ANSYS有限元软件分析结构基于位移性能下的正常使用极限可靠度。经软件分析得出在所给几何尺寸、材料特性、预应力、恒荷载以及活荷载等随机变量作用下,结构基于位移正常使用极限状态下的可靠度是良好的;对结构位移影响最大的变量是预应力,影响最小的变量是混凝土板肋的截面尺寸;可靠度为95%的结构最大位移值是60mm。

According to the thought of beam string structure,prestressing structure was presented that it was joined by combined grid and cable by pole support.It was combined grid string branch structure.A calculation model of string branch grid was founded.The reliabilty was solved when the structure was acted by presented random variables including geometry size,material properties,prestress,dead loads and live loads.After the solution was done we come to the conclusion that the reliability is favorable while the structure is normal used.The variables that affect displacements and belly bars stress much more are cable prestress and much less are section size of concrete slab.The maximal displacement value is 60mm when the reliability is for 95%.