中文摘要：

镇江体育会展馆屋盖属于大跨度张弦桁架结构.首先以整体结构为研究对象,除对单榀张弦桁架进行设计外,着重对张弦桁架的侧向支撑进行了简化和优化设计.根据本工程的特点,沿整体桁架四周增加了对称拉索.然后对优化前后结构的力学性能进行了分析.分析结果表明：优化后结构更加简单,施工安装难度大大降低,结构应力峰值减小,结构挠度减少;优化后结构的基频增加,地震响应峰值减小,竖向刚度大大增加,结构抵抗地震能力增强.因此,张弦桁架结构优化分析应根据整体结构的特点,除进行单榀张弦桁架优化外还应重视其侧向支撑的设计优化.

英文摘要：

The roof of Zhenjiang sports conference exhibition pavilion is a large span string truss structure. First, optimal designing of single string truss structure is done. Then lateral support is simplified and optimized and symmetrical cable is added. Mechanical character is compared between before and after optimal design. Compared with that before optimal design, the structure, the difficulty of construction, the maximum of axial stress, the maximum of axial stress and the middle vertical displacement after optimal design is simpler. The first natural frequency after optimal design is more greater and the vertical stiffness, the capacity of resistance earthquake after optimal design is greater. Therefore, optimization analysis of string truss sturcture should be based on the behavior of the overall structure. In addition to the single beam piece of string truss optimization, its lateral support design optimization should be paid attention to.