中文摘要：

目前针对盾构隧道掘进引起周围地层附加应力的研究较少，且既有成果一般均假定施工场地为均质土体。基于层状地基基本解，结合虚拟力法，建立了考虑分层效应的盾构隧道施工扰动地层附加应力的分析方法，重点研究了盾构施工正面附加推力、盾构与土体间掘进摩擦力引起的地层附加应力。结合上海典型分层地基工程实例，分析了盾构施工引起的附加应力分布规律，且与均质土体工况下的计算结果进行了对比研究，考察了地基分层效应对扰动地层应力场的影响。计算结果表明：盾构与土体间掘进摩擦力与正面附加推力引起的土体附加应力分布规律较为相似，靠近开挖面时附加应力衰减较快且影响范围一般较小，而远离开挖面时应力衰减明显变慢，在实际工程中要重视掘进摩擦力和正面附加推力造成的施工风险；此外，考虑分层效应与常规不考虑分层效应时的附加应力场有较大差别，在设计中应重视地基非均质性带来的影响。成果可为合理制定层状地基中盾构隧道施工对临近管道以及建筑物的保护措施提供一定的理论依据。

英文摘要：

The current researchers pay little attention to the additional stresses of disturbed soils caused by shield tunneling, and all the existing results are based on the assumption of homogenous soils. A theoretical approach, combined with the fictitious force method based on the basic solution for layered foundation, is proposed to analyze the additional stresses of disturbed soils induced by shield tunneling considering the layered effects. The additional stresses induced by the bulkhead additional pressure and the propulsion friction force between the shield machines and the surrounding soils are emphasized. A tunneling case in Shanghai for layered foundation is employed to analyze the distribution rules of the additional stresses caused by tunneling. Furthermore, the comparative researches with a case of homogenous soils are also conducted to study the effects of layered characteristics on disturbance stress field. The results show that the distribution rules of the additional stresses caused by the propulsion friction force are similar to those induced by the bulkhead additional pressure. The additional stresses attenuate quickly in the region close to excavation opening, and the influence sphere is generally small. The additional stresses attenuate slowly in the region away from excavation opening. The construction risk due to the friction force and bulkhead additionalpressure should be highlighted. In addition, there are great differences in the characteristics of the stress fields with and without considering the layered effects. Therefore, the influence of non-homogenous soils should not be ignored in the design. It mayprovide a certain basis for correct preparation of protective measures of adjacent pipelines and buildings induced by shield tunneling in layered soils.