基于概率统计的不同支护参数下白马隧道预留变形量研究

Study on Reserved Deformation in Baima Tunnel Based on Probability Statistics under Different Support Parameters

受地应力水平和围岩工程性质的影响,隧道的稳定往往跟隧道极限位移密切相关,但由于极限位移现场不易测定,为了方便起见,多采用预留变形量替代极限位移。隧道施工预留变形量的合理选取,可以避免预留变形量过小导致的隧道变形侵限和过大造成的施工成本方面的浪费。文章选取在建九绵高速白马隧道为研究对象,选取两种典型的支护参数,运用概率统计的方法对这两种支护参数下的预留变形量进行研究,并得出了这两种支护参数下的预留变形量建议值,以期为类似工程提供参考。

Due to the effect of the ground stress level and the engineering properties of surrounding rock,the stability of a tunnel is often closely related to its ultimate displacement.However,because the ultimate displacement can be uneasily measured on the site,it is more convenient to replace the ultimate displacement with the reserved deformation.Reasonable selection of reserved deformation in tunnel construction is helpful to avoid the deformation invading in the tunnel caused by too small reserved deformation and the waste of construction cost caused by too large reserved deformation.With the Baima Tunnel of Jiuzhaigou-Mianyang Expressway under construction as the research object in this paper,two typical support parameters were selected and the method of probability statistics was used to study the reserved deformation under these two support parameters to obtain the recommended values of the reserved deformation under these two support parameters in order to provide references for similar projects.