重载张弦梁结构设计关键技术研究

Research on key techniques of heavy loaded beam string structure

对重载张弦梁结构中混凝土板的组合作用、结构承载力、撑杆抗滑、水平地震作用传递方式以及结构平面外摆动等问题进行研究。通过有限元分析、理论推导和对相关工程实践的总结得出:混凝土板的组合作用可以减小重载张弦梁结构上弦构件的内力、增大结构承载力、提高结构的弯曲刚度;建议在撑杆底端分段设置抗滑索,避免撑杆底端向跨中滑移;利用连续混凝土板的受剪作用可将重载张弦梁所产生的水平地震作用传递给剪力墙等抗侧力构件;重载张弦梁结构没有发生整体或局部面外摆动的可能。据此提出结构中各主要构件的内力计算式,可用以初步确定重载张弦梁各主要构件的截面规格。

Several issues of heavy loaded beam string structures were investigated,including composite action of concrete slabs in the structure,bearing capacity of the structure,anti-sliding of struts,transfer path of horizontal seismic inertia forces and out-of-plane swing of the structure. Based on finite element analysis,theoretical deductions and related engineering experience,conclusions are as follows: the composite action of concrete slabs can reduce internal forces of top chords and increase bearing capacity and bending stiffness of the structure; setting anti-sliding cables at the bottom of struts is recommended to prevent the bottom of struts from sliding towards mid-span; using shear capacity of continuous concrete slabs,the horizontal seismic inertia forces of the structure can be transferred to lateral force-resisting members,such as shear walls; the whole or local out-of-plane swing in the structure is not possible;equations for the main member internal forces calculation,which can be used to preliminarily estimate main member cross sections,are proposed.