新广州站三向张弦梁结构优化设计

基于运用APDL语言对新广州站工程三向张弦梁结构建立的参数化模型，利用一阶优化方法，对初始结构进行全构件截面和形状参数的综合优化.并在矢高和垂度确定的情况下，分别采用分级优化和综合优化分析了构件截面的合理取值.分析结果表明：矢高和垂度是三向张弦梁结构设计中极为重要的设计参数，新广州站三向张弦梁结构的最佳矢高为9.189 m，其垂跨比应不小于0.034，下弦垂度和上弦矢高的经济比值为0.22~0.23.上弦拱构件在结构中占的比重较大，可以通过减小拱截面的壁厚来降低结构的用钢量.并通过综合优化得到新广州站三向张弦梁的最佳梁弦刚度比为1.23×10-4

Optimization Design of Tri-directional Beam String Structure of New Guangzhou Railway Station

The APDL language was used to obtain the parameter model of tri-directional beam string structure (TBSS) of new Guangzhou Railway Station. Then design optimization was conducted for the effective cross-sections and geometry parameters of TBSS with the first-order method. And when the rise and sag were fixed, the proper structural cross-section was also discussed with graded and integrated optimization method respectively. The results show that the rise and sag are very important design parameters of TBSS. The optimum rise of upper arch of TBSS for new Guangzhou Railway Station is 9.189 m; the sag to span ratio of cable is not less than 0.034; the economical rise to sag ratio is about 0.22~0.23. It can also be found that the weight ratio of upper arch elements to the whole structure is large, so the amount of steel can be reduced by decreasing the thickness of upper arches. And the optimum rigidity ratio of beam to cable of TBSS of new Guangzhou Railway Station is 1.23×10-4 by integrated optimization.