新型散装粮食半地下平房仓的自振特性及地震响应分析

Natural vibration characteristics and seismic response analysis of a new type of semi-underground horizontal warehouse to storage bulk grain

结合某粮食现代物流中心半地下平房仓实际工程,采用有限元法对柱支撑拉杆、钢支撑加固拉杆和吊杆连接拉杆三种不同拉杆形式的新型半地下平房仓进行了数值模拟分析研究。分析结果表明:柱支撑拉杆形式结构整体性能差,产生局部振动,采用钢支撑加固拉杆后拉杆体系刚度增加,整体性能得到改善,但柱支撑形式过多占用储粮空间,而吊杆连接拉杆的整体性较好,结构刚度比较合理,满足抗震计算精度要求。对吊杆连接拉杆的新型拉杆体系的半地下平方仓的动力特性进一步分析,发现结构主要振型符合以水平方向运动为主的规律。将振型分解反应谱法的分析结果与规范计算方法的结果进行对比分析,发现结构的整体位移及应力分布规律一致。该新型粮仓结构在7度多遇地震作用下,满仓时规范计算结果大于反应谱分析的结果,但两种方法得到的结构整体抗震性能良好,且按照规范结果进行抗震设计时结构会更加安全。

Based on the semi-underground horizontal warehouse of a modern grain logistics center,the finite element method is used to simulate and analyze three new semi-underground tension bar systems that structure forms respectively are column bracing rod,steel bracing tie bar and hanging rod connecting rod.Analysis results show that the integrity of the pull rod strengthened by column support is poor for resulting in local vibration.The formal stiffness of the pull rod strengthened with steel support is increased and the integrity is improved,but the support column is not conducive to grain storage.While the stiffness of the structure is reasonable,the integrity of the connecting rod is good and is up to the mustard of accuracy to seismic calculation.The dynamic characteristics of the semi-underground square silo of the new pull rod system connected with the suspender are further analyzed.It is found that the main vibration modes of the structure accord with the law of horizontal movement.By comparing the analytical results of modal decomposition response spectrum with those of the standard calculation method,it is found that the global displacement and stress distribution of the structure are consistent.Under the action of seven degree earthquake,the calculated results of the code are larger than those of the response spectrum analysis,but the overall seismic performance of the structure obtained by the two methods is good,and the structure will be safer when the seismic design is carried out according to the code results.