拱形管桁架平面外稳定有限元分析

Finite Element Analysis of Plane Stability of Inverted Triangular Space Truss Arch

为了研究倒三角形拱形管桁架在不同荷载形式、边界条件和尺寸参数下的平面外稳定承载力,采用有限元方法,对倒三角形拱形管桁架进行特征值屈曲分析和非线性分析。结果表明:全跨均布荷载的平面外承载力大于半跨均布荷载的平面外承载力;铰接拱脚的平面外承载力小于销轴拱脚以及固支拱脚;矢跨比越小,平面外稳定承载力越大;宽高比越大,平面外稳定承载力越大。采用全跨均布荷载、固支或销支拱脚、小矢跨比和大宽高比,能最大程度发挥结构的平面外稳定性。

In the paper the stability of out plane of inverted triangle space truss arch are studied under different loads,boundary conditions,and dimension influence. The finite element method is employed to analyze the eigenvalue stability analysis and nonlinear analysis. The results show that the stability of out plane under full span uniform load is larger than one of half span uniform load. Stability of out plane under simple support is less than one of the pin support and fixed support. The larger rise span ratio does the lower out of plane stability does. The larger aspect ratio does the higher out of plane stability does. Therefore,in order to maximize stability of out plane of structure,full span uniform load,pin support or fixed support,lower rise span ratio and larger aspect ratio should be used in the triangular space truss arch.