【摘要】 为得到地震作用下无衬砌隧洞的力学规律,将有限元强度折减法和具有拉和剪破坏分析功能的大型有限差分程序FLAC相结合,并将其引入到隧洞的稳定性分析中。在黄土无衬砌隧洞静力分析基础上,提出地震作用下动力有限元静态分析以及完全动力2种稳定性分析方法,在分析时同时考虑隧洞的拉破坏与剪破坏,从而得出黄土隧洞在动力情况下首先是隧洞顶部出现局部拉破坏然后是侧边整体破坏的破坏机制,同时也验证有限元强度折减法不仅能够用于隧洞静力分析而且能够用于隧洞动力稳定分析,从而为无衬砌黄土人居洞室的抗震设计提供理论依据,也可作为有衬砌黄土隧道的地震反应分析的基础。更多还原

【Abstract】 In order to obtain the regularity of mechanics for an unlined tunnel during earthquake,strength reduction finite element method and a large finite-difference program FLAC with tensile and shear failure analyses are combined and introduced into the tunnel stability analysis.Based on static analysis of loess unlined tunnels,a seismic dynamic finite element static analysis and a complete dynamic stability analysis methods are proposed. The analysis takes into account the tunnel tensile and shear failure to get the failure mechanism of loess tunnel with outside drive.Partial tensile failure is taken place at the top and then the general demolition is took place at the broadside of the tunnel.And it is found that the strength reduction finite element method can be used not only to tunnel static analysis but also to tunnel dynamic stability analysis.This analysis can provide a theoretical basis for seismic design of unlined cavern loess habitat,and it can be used as a foundation for seismic response analysis of loess tunnel with lining.更多还原