In this study, the magnitude of lining pressure required for stability of an elliptical tunnel in cohesive-frictional soil has been determined by using lower bound limit theorem in conjunction with finite elements and linear programing optimization technique. A uniform normal pressure (σ_i) is applied on the tunnel periphery to support the tunnel by means of lining or anchorage system. The evaluated support pressure is presented in terms of normalized pressure as σ_i/c acting on the periphery of a tunnel embedded in undrained cohesive and cohesive-frictional soil for different combinations of H/B, D/B, γB/c and ϕ where H is cover depth of tunnel from ground surface, B and D are width and depth of tunnel, respectively, and c, ϕ and γ are cohesion, peak friction angle and unit weight of soil, respectively.

在这项研究中，通过使用下限极限定理，有限元和线性规划优化技术，确定了黏性摩擦土中椭圆形隧道的稳定性所需的衬砌压力大小。均匀常压（σ_我）施加在隧道周，以支持由衬里或锚固系统的装置的隧道。所评估的支撑压力被归一化的压力的方式来呈现σ_我/ ç作用于嵌入在不排水凝聚力和的不同组合凝聚力-摩擦土壤隧道的周H / B，d / B，γB/ C和φ，其中H是隧道从地表的覆盖深度，B和D分别是隧道的宽度和深度，c，ϕ和γ分别是内聚力，峰值摩擦角和土壤单位重量。