隧道施工中围岩与支护结构的黏弹性分析

本文结合某高速公路隧道设计与施工，利用黏弹性理论，对隧道围岩与支护结构时间相依应力与位移进行了研究。首先，将隧道开挖后围岩受力分析视为具有初始应力、在洞周位移作用下的边值问题，导出了隧道时间相依的围岩与支护结构应力与位移，结果表明，其应力和位移与隧道围岩和支护结构间相互作用相关。然后，利用变形协调条件，导出了隧道围岩与支护结构间的相互作用，结果表明，围岩、初期支护与二次衬砌之间的相互作用不仅与围岩和衬砌的材料性质、结构尺寸相关，而且与施做初衬和二衬的时间相关。最后，结合具体隧道设计与施工，利用本文时间相依应力，对围岩应力释放与支护施做时机、载荷分配与支护结构受力分析进行了探讨，给出了不同荷载分担比下二次衬砌的受力与变形，为隧道施工与设计提供参考。

Viscoelastic analysis of the stress and displacement in tunnel surrounding rock and support during the process of tunnel construction

In this paper, combined with the design and construction of a tunnel, and using viscoelasticity, time-dependence stress and displacement in tunnel surrounding rock and support have been studied. Firstly, to stress analysis of the surrounding rock and support as a boundary value problem with the initial stress under the action of the displacement in the tunnel surrounding rock after tunnel excavation, the time-dependence stress and displacement in tunnel surrounding rock and support have been derived, these depend on the interaction between tunnel surrounding rock and support. Then, the interaction between tunnel surrounding and support has been derived by compatibility of deformation, the interaction is not only dependence on material property and size of tunnel surrounding and support, but also the time of making supports. Finally, combined with the design and construction of a special tunnel, and using the time-dependence stress in this paper, the stress release of the tunnel surrounding rock and load distribution ratio and the stress in support have been calculated, and the displacement and stress in the second lining under different load distribution ratio have been given. These can be provided a reference for the construction and design of the tunnel.