新型斜拱形单层球面网壳结构方案选型分析

STRUCTURE SELECTION OF INCLINED ARCH SINGLE-LAYER SPHERICAL LATTICE SHELL

受桥梁中斜靠式拱桥启发,提出一种新型斜拱形单层球面网壳体系。以环杆布置数量、环杆布置位置、径向直拱布置方式、结构环向分频数为参数,采用ANSYS软件对4类共62个结构模型进行结构静力及稳定性分析,研究内力峰值、竖向挠度、稳定承载力与用钢量的变化规律,获得合理的杆件布置方式。研究结果表明:对斜拱形单层球面网壳,为满足结构稳定承载力要求,宜设置环杆,且两圈环杆对结构力学性能改善更显著;结构环杆设置位置的外移对结构力学性能有利;考虑结构经济性和通透性,可不另设径向直拱;结构环向分频数宜取6频,一般不超过8频。

Based on leaning-type arch bridge,the paper proposed a new type of single-layer spherical lattice shell composed of inclined arches.The mechanical properties analysis of 4 categories and 62 models had been proceeded by ANSYS finite element analysis.The static and stability performance of the structure were carried out with parameter changes study on the variations of its peak internal force,deflection,stability capacity and steel consumption so as to obtain reasonable member arrangement.The results showed that it was advisable to set inner ring bar to meet the stability capacity requirements and double inner bars could improve the mechanical properties more significantly.The mechanical properties of the structure could be improved with the position of inner ring bar arranged varying from the inside to outside.Comprehensively considering economy and permeability,the number of circumferential divisions of the structure should not be too large,6 or 8 divisions was acceptable.