考虑支承刚度对大跨空间网格结构的动力影响

Dynamical Effect on Large-span Space Lattice Structures Considered Supporting Stiffness Degree

对于支承在周边混凝土框架或柱子上的大跨空间网格结构进行地震反应分析时,常把此类体系的网架和网壳结构与支承分开考虑。应用时程分析法,考虑多维多点输入,比较了上部结构与下部支承共同作用的动力分析与不考虑下部支承作用的动力分析。计算结果表明,在结构自振频率、杆件内力方面,考虑整体分析时得到的结果有很大不同。对大跨空间网格结构进行多维多点地震分析、设计时应采用整体分析方法。

When analyzing the seismic response of large-span space lattice structures supported by concrete frame or pillar in circumference, this kind of lattice structures and their supports are usually considered separately. The dynamical analysis with the action of the upside structure and the below supports together is compared with the dynamical analysis without the action of supports based upon＇the time-history method under muIti-demension and multi-surpport excitations. It is pointed out that the results obtained when considering the whole action are different in the aspects of the self-vibration frequency of structure and the inner force of the bars. So the whole analysis should be adopted when studying the large-span space lattice structures.