多层采空区影响下隧道内力变化的数值研究

摘要:

针对具体工程案例，建立了隧道下穿两层、上覆一层的采空区的数值模型，得到了隧道开挖后隧道变形、衬砌结构内力及地层变化的规律，探究了多层采空区对隧道的叠加效应。主要发现有：隧道上、下的采空区对隧道变形的影响规律不同；多层采空区的存在大大增加支护结构的截面偏心距，从而降低结构的承载能力；有无采空区时隧道周围的地层变形特征差异显著。

Abstract:

According to the specific engineering case, the numerical model of the goaf with two layers under the tunnel and one layer above is established. The laws of the deformation of the tunnel, the internal force of the lining structure and the change of the stratum after the tunnel excavation are obtained, and the superposition effect of the multi-layer goaf on the tunnel is explored. The main findings are as follows: the influence of goafs above and below the tunnel on the deformation of the tunnel is different; the existence of multi-layer goafs greatly increases the section eccentricity of the support structure, so as to reduce the bearing capacity of the structure; when there is no goaf, the deformation characteristics of the strata around the tunnel are significantly different.