盾构隧道同步注浆对管片上浮的影响分析

为分析广州地铁18号线沙西站—石榴岗站区间隧道同步注浆对盾尾管片上浮与受力的影响,建立考虑围岩随机裂隙分布的流固耦合数值模型。基于牛顿流体与宾厄姆流体推导管片壁后注浆压力分布解析解,通过将数值模拟获得的注浆压力与解析解对比,验证数值模型的适用性,并分析同步注浆作用下围岩和隧道结构的变形及应力特征。结果表明:所建的数值模型能较好地模拟同步注浆压力的分布;注浆对地层的初始位移场影响较大,导致整个隧道周围地层均表现为隆起;管片内外轮廓线的Mises应力与压应力差异较大,且分布形式正好相反。

Influence of Synchronous Grouting on Segment Floating in Shield Tunnel

In order to analyze the influence of synchronous grouting on the uplift and stress field of shield tail segments,a fluid-solid coupling numerical model considering the distribution of random fracture was established.Based on Newtonian fluid and Bingham fluid,the analytical solution of grouting pressure distribution behind segments was derived.The applicability of the numerical model was verified by comparing the grouting pressure obtained by numerical simulation with the analytical solution.The results show that:the numerical model can better simulate the distribution of synchronous grouting pressure.Grouting has a great influence on the initial displacement of the stratum,resulting in the uplift of the whole stratum around the tunnel.The Mises stress and compressive stress of the inner and outer contour of the segment are quite different,and the distribution form is just the opposite.