弦支穹顶结构在地震作用下的动力稳定性研究

本文使用Ansys计算软件,采用时程响应方法,研究了地震荷载作用下结构参数、均布荷载及索的引入对弦支穹顶动力稳定结构影响.计算过程中,采用逐步增大地震荷载幅值的方法,把位移响应突然增大时的地震荷载幅值作为结构的稳定临界荷载.计算结果表明,结构稳定临界荷载随着跨度的增大而线性降低,结构的稳定性提高;跨度取固定值时,在某一矢高下,结构有着最佳的动力稳定性能,超过或者低于此矢高值结构稳定性均下降;随着均布荷载增大,结构稳定临界荷载降低,稳定性能减弱;当外荷载增大到一定程度时,结构稳定性的降低幅度反而减小;索的引入大大改善了结构在地震荷载作用下的动力稳定性能,从而使得弦支穹顶结构动力稳定性能大于相应单层网壳的动力稳定性.

Analysis on the dynamic stability of suspen-dome

In the paper analysis on dynamic stability of suspen-domes is carried out with the structure parameters such as span and rise with the program Ansys and Time-History method.During the analysis,the seismic excitation amplitude is supposed the dynamic stability critical excitation when the structure displacement sudden increases.The results show that the stability increase linearly when the span increases and also increases linearly when the rise increases at the beginning,while it decreases linearly when the rise exceed a certain numerical value.And it also demonstrates that the stability declines when loads increase.But it narrowly decline when the loads increase to a certain value.And the suspen-dome is showed to have superiority to single-layer in stability due to the rings adopted.