中文摘要：

研究目的：超大直径盾构下穿建筑沉降敏感区对地层扰动大，极易诱发地面沉降，导致流砂、管涌，给开挖面稳定性、运营安全、立体化施工带来较大挑战，而现有的研究成果主要针对浅埋小直径盾构，且考虑的地层损失定义各不相同，如何利用地层损失研究盾构施工地层损失与地面沉降的关系亟待开展。本文以某超大直径盾构在复杂环境下下穿建筑沉降敏感区工程为例，计算常规地层损失率、极端地层损失率下，隧道二维、三维地面沉降相应的地层损失率和相应地层损失率对应的地面沉降，探讨盾构施工与地层损失、地面沉降的关系。研究结论：通过研究得出：（1）盾构施工时，在5％的地层损失率范围，每增加0．1％的地层损失率，相应的地表最大沉降约增加3～4mm；（2）平均盾尾地层损失率每增加0．5％，最终盾构沉降增加约8mm；（3）盾首部分的地层损失与盾尾部分的地层损失共同影响总的地面沉降；（4）提出发展一套基于“地面沉降指标的地层损失控制率”的盾构控制方法；（5）本文可对深入开展盾构施工诱发的地面沉降、防治地质灾害，保证隧道工程合理设计、安全施工提供参考。

英文摘要：

Research purposes： A large area of soil is disturbed duringshield under - passed the building - sensitive region, but it isvery easilyindueed byground settlement, lead toquicksand, and piping, brings a big challenge to the facestability, operation security, and three -dimensional construction. The current research ofground settlementmainly concentrates on the small shield, and consideringdifferent definition aboutstrata loss. How to use thestrata loss to research the relationship of strata loss and ground settlement during shield construction is still one of the most sophisticated problems needed to be solved urgently. This paper, taking a super - large - diameter shield under - passed the building - sensitive region in a complex environmentas an example, the corresponding strata loss of ground settlement of 2D and 3D, and its corresponding ground settlement are calculated under the condition of strata loss from conventional to extreme. The relationship among shield construction, strata loss and ground settlement are discussed. Research conclusions： （ 1 ） The maximum ground settlement for every increased O. 1% of strata loss was increased 3 -4 mm under the condition of strata loss 5~. （2）The final settlement for every increased 0.5% of average strata loss of shield tail was increased 8 ram. { 3 ） By the common influence of strata loss of shield head and shield tail, the total final settlement was formed. （4）It is proposed that development of a set of methods for shield control by using ground settlementin dicators of strata loss control rate. （5） This paper provides the valuable reference to the study on the ground settlement, disaster prevention, tunnel design, and construction.