西宁体育馆管桁架钢屋盖结构自振特性分析及抗震性能评价

Analysis of Natural Vibration Characteristics and Evaluation of Seismic Behavior of Steel Pipe Truss Roof Structures of Xining Stadium

以西宁市海湖新区体育馆为对象,应用有限元软件ANSYS进行了模态分析,研究了高跨比和约束形式对此类结构自振特性的影响.分析结果显示,高跨比仅对结构第一阶自振频率的影响较明显;主桁架结构部分的约束形式对整体结构的自振特性影响较大.该屋盖结构的自振频率分布比较密集,结构的刚度和质量分布比较均匀,抗震设计时需要考虑高阶振型的参与作用.另外,采用时程分析法研究了此体育馆在多维罕遇地震作用下的响应.结果显示,此类交叉桁架结构具有很好的抗震性能.

With the steel roof structure of Xining stadium as the research object,the modal analysis was done with ANSYS, an finite element software, and the effects of the ratio of rise to span and constraint forms of the natural vibration properties of this structure was studied. The results show that the impact of the depth-span ratio on the first order inherent frequency is obvious, the constraint forms of the main truss structure have a major effect on the natural vibration characteristics. The distribution of the natural frequency of vibration of the structure is very dense,the distribution of stiffness and mass is well distributed and the high-order vibration mode must be considered for the seismic design. In addition,the structural response under the action of rare earthquakes is analyzed by the time history analysis method and the results show that this truss structure has good seismic behavior.