盾构隧道穿越饱和砂土层的流固耦合分析  

Fluid-structure interaction analysis of shield tunnels crossing saturated sand layers

作　　者：高子明 GAO Ziming(China Railway 21 First Group Rail Transit Engineering Co.,Ltd.,Jinan 250117,China)

机构地区：[1]中铁二十一局集团轨道交通工程有限公司,济南250117

出　　处：《低温建筑技术》2024年第11期131-136,共6页Low Temperature Architecture Technology

摘　　要：区间盾构穿越砂土层时,因其洞周土层含水量大,导致砂土层的渗透系数较大,极易发生突然涌水、涌砂事故。文中采用有限元方法,分析了饱和渗流作用下,双线盾构隧道贯通后土体及衬砌结构的受力特性。结果表明在左线隧道开挖贯通后,注浆层内水平方向的应力比未注浆区域大,发生挤压流动,带动拱底向上隆起;右线隧道上方地表沉降小于左线隧道;隧道周围土体强度和承载力水平均有所下降。实际施工过程中,应防止衬砌拱顶及拱底处向上的应力过大,应对隧道的不同拱腰处采取相应的加固、支护措施,增大洞口段的支护强度,保证结构的稳定性。During the crossing of sand layers by interval shield tunneling,high water content and significant permeability in the sand layers can lead to sudden water influx and sand eruption incidents.This study utilizes the finite element method to analyze the stress characteristics of the soil and lining structures after the completion of a dual-line shield tunnel under saturated seepage conditions.The results indicate that after the excavation of the left-line tunnel,the horizontal stress within the grouting layer is greater than in the non-grouted areas,causing extrusion flow and upward arching at the tunnel bottom.Ground settlement above the right-line tunnel is less than that above the left-line tunnel,and the strength and bearing capacity of the surrounding soil decrease.During actual construction,it is essential to prevent excessive upward stress on the lining crown and bottom.Appropriate reinforcement and support measures should be implemented at different arch waist locations to increase the support strength of the portal section,ensuring the stability of the structure.

关 键 词：盾构隧道 双线隧道 砂土层 流固耦合 力学特性 

分 类 号：TU441.4[建筑科学—岩土工程]