埋深和坡度对浅埋隧道围岩稳定影响的敏感性分析

Sensitivity Analysis of the Effect of Depth and Slope Gradient on the Surrounding Rock Stability for Shallow-Buried Tunnels

埋深和坡度对围岩稳定影响的敏感性分析是浅埋隧道选线及施工方案确定的一项重要研究内容。文献[1]应用自行开发的程序分析了浅埋隧道不同偏压角及埋深下围岩的变形规律。在此研究基础上,文章提出了一种敏感性分析方法,研究隧道埋深和坡度对围岩稳定影响(地表沉降、拱顶沉降、围岩塑性区分布)的敏感性。研究结果表明:地表和拱顶沉降对隧道埋深比较敏感,对偏压角的敏感性相对较小;而围岩塑性区面积对偏压角的敏感度要大于隧道埋深。研究结果对浅埋隧道的设计和施工具有一定的指导价值。

The sensitivity analysis of the effects of buried depth and slope gradient on surrounding rock stability is very important for alignment selection and the determination of a construction scheme for a shallow-buried tunnel. The deformation rules of surrounding rock under different bias angles and buried depths have been analyzed in pre- vious work, and based on this, a sensitivity analysis is proposed to study the sensitivity of the effects of tunnel over- burden and slope gradient on the stability of surrounding rock （surface settlement, vault settlement and plastic zone distribution）. The results show the surface settlement and vault settlement are relatively sensitive to tunnel overbur- den but not so sensitive to the bias angle; as for the plastic zone area, it is more sensitive to the bias angle than the buried depth of tunnel.