桁架式跨越通过高地震烈度区的抗震分析

Seismic analysis on the truss overhead crossing pipeline across high-intensity earthquake area

西气东输管道工程中卫黄河穿跨越工程设计采用多跨桁架式跨越方案,选择微机结构分析通用程序SAP84和空间杆系结构有限元分析程序GNSAP作为跨越工程的抗震分析软件,以振型分解反应谱法为主,时程分析方法做补充,讨论了地震时程分析法在高地震烈度区跨越结构中运用的可行性。提出了输气管道通过地震断裂带时,跨越结构吸收地震断裂带错动时的抗震措施。抗震分析结果表明:大型桁架跨越方式具有明确的受力简图、合理的刚度分布和优越的抗震性能,与抗震构造措施结合,可以确保输气管道的安全。

The multi-span truss overhead crossing design scheme was adopted in the Yellow River Crossing Project of Zhongwei Pipeline in West-to-East Gas Pipeline. SAP84 and GNSAP were chosen as the seismic analysis software in this crossing project. Response spectrum analysis method was taken as a main tool,and time-history analysis as an assistance to research the application of the latter in crossing structure to cross the high-intensity earthquake area. Regarding the gas pipeline,the seismic measures for overhead crossing structure to bear the earthquake fault zone diastrophism was proposed. Results from the seismic analysis indicated that the large-scale truss overhead crossing structure had a clear force diagram,reasonable stiffness distribution and stronger seismic performance,and if it was integrated into the seismic measures,the safe running of gas pipeline would be provided.