赵俞成 艾兵兵 刘东 宋强 冯伟 艾志伟

摘要：為研究隧道施工顺序对隧道开挖的影响，采用三维有限元分析方法模拟某垂直穿越隧道的开挖过程.基于砂土的亚塑性本构模型并考虑土体的小应变刚度，分析施工顺序对垂直交叉隧道的影响，研究对既有隧道附近土体的应力传递机制.研究结果表明：与无既有隧道工况相比，既有隧道的存在使得最大沉降量降低14%；新建隧道在既有隧道上方时，地表沉降较大，但影响范围小，当掌子面接近既有隧道中心线时，既有隧道的应力由拱顶传递至拱肩；当掌子面距离既有隧道中心线后方3D和前方6D之间时，应力释放对既有隧道的影响显著；新建隧道在既有隧道下方时，既有隧道产生的变形和弯矩更大；在垂直交叉隧道施工中，应充分考虑施工顺序对地表沉降、既有隧道的影响.

关键词：隧道开挖；垂直交叉隧道；地表沉降；隧道变形；应力传递机制；数值分析

中图分类号：TU43文献标志码：A

基金项目：国家自然科学基金资助项目（51779221，51939010），National Natural Science Foundation of China（51779221，51939010）；浙江省重点研发计划项目（2018C03031），Key Research and Development Program of Zhejiang Province（2018C03031）

Three-dimensional Finite Element Study of Tunnel Advancing to Adjacent Perpendicularly Crossing Tunnel

ZHAO Yucheng1，AI Bingbing2，LIU Dong2，SONG Qiang2，FENG Wei3，AI Zhiwei3

（1. Research Center of Coastal and Urban Geotechnical Engineering，Zhejiang University，Hangzhou 310058，China；2. Project Department of Hangzhou Metro，China Railway NO.2 Engineering Group Co Ltd，Hangzhou 310058，China；3. Hangzhou Metro Group Co Ltd，Hangzhou 310058，China）

Abstract：In this study，a three-dimensional finite element analysis method was used to simulate tunnel excava-tion nearby a perpendicularly crossing existing tunnel，in order to investigate the effects of construction sequences on cross-cutting tunnels. The hypoplastic constitutive model of sand and soil is adopted and the soil small-strain stiffness is considered in the numerical analysis，so as to study the effect of construction sequences on cross-cutting tunnels as well as the stress transfer mechanism of the soil near the existing tunnel. The results show that the existence of the ex-isting tunnel reduces the maximum settlement by 14% when compared with the condition without the existing tunnel； when the new tunnel is above the existing tunnel，the settlement is larger，but the impact range is smaller. When the tunnel face approaches the centerline of the existing tunnel，the stress of the existing tunnel is transferred from the vault to the abutment；when the tunnel face is between 3D behind and 6D in front of the centerline of the existing tun-nel，the effect of stress relief on the existing tunnel is significant； when the new tunnel is under the existing tunnel，the deformation and bending moment of the existing tunnel are greater. In the construction of vertical cross tunnels，the impact of the construction sequence on the ground settlement and the existing tunnel should be considered comprehen-sively.

Key words：tunneling excavation；perpendicularly crossing tunnels；ground surface settlement；tunnel deforma-tion；stress transfer mechanics；numerical analysis

近几十年来，研究土体-隧道相互作用的方法多种多样，包括现场监测、模型试验、经验/分析方法和数值模拟[1-5]，然而，大多数研究集中在平行隧道和背驮式隧道，对垂直交叉隧道研究较少.此外，大多数研究使用简单的弹性-理想塑性本构模型对隧道相互作用进行数值分析[6-9]，没有考虑由于应力增加导致土体剪切模量的改变以及刚度的变化.基于……