靖江市体育中心体育馆上承式张弦桁架拱设计研究

Design and research on top-bear truss-arch string structure of Jingjiang Sports Center Stadium

靖江体育中心体育馆屋面为屋脊沿矩形对角线布置的双坡屋面,为统一各榀桁架形状及受力、优化用钢量,设计出一种可适用于不规则坡屋面的新型上承式张弦桁架拱结构。以用钢量最小为目标,采用二次开发的ANSYS优化设计程序,对控制该结构形状的各参数进行优化。结果表明：当桁架跨度小于100m时,宜采用在跨度三分点附近布置2根撑杆的结构形式;拱脚处桁架高度建议取0.45-0.55倍的结构高度,拱脚距支座距离建议取0.06-0.08倍的跨度;结构用钢量随高跨比的增大而减小,当高跨比取0.10时,用钢量接近最优值。

Jingjiang Sports Center Stadium has the double-pitch roof with ridges arranged along the rectangular diagonal line. In order to unify the shape and force of each truss and optimize the steel consumption,a new type of top-bear trussarch string structure was designed to be suitable for irregular pitch roof. A further-developed optimization program based on ANSYS was used to optimize key parameters controlling the shape of top-bear truss-arch string structure to reach the goal of the minimum steel consumption. The results show that when span of top-bear truss-arch string structure is less than 100 m,two struts should be arranged at third-point of the structure. The ratio of truss height at the arch foot to total height should be 0. 45 to 0. 55. The ratio of arch foot span to total span should be 0. 06 to 0. 08. With the increase of high-span ratio,the steel consumption becomes smaller. When high-span ratio is 0. 10,the steel consumption approaches the optimal value.