中文摘要：

基于上海M8线等双圆隧道工程实例,开展双圆盾构衬砌结构-软土层相互作用规律的模型试验研究。通过系列正交试验考察软土层与双圆盾构衬砌相互作用的参数效应,观测此软土层作用下双圆盾构衬砌的结构内力响应。对比发现：间隔1环或2环（1.2-2.4m）布设中立柱,可保证衬砌变形量控制在3mm要求范围,并与M8线工程全环布设的实效吻合。内力传递的折减系数为0.61-0.97。利用粒子成像测速技术PIV2C软件与试验拍摄系统对比现场实测数据,给出地层沉降及颗粒运移规律的跨尺度对比分析,结果表明：地层沉降曲线的影响规律从地表至衬砌顶部表现为“U型-V型-W型”变化,塌落区面积比约为0.85,粒子成像测速技术PIV可较好揭示双圆盾构软土层马鞍槽及塌落拱形成的瞬态运移规律。

英文摘要：

Based on the DOT （Double-O-Tube） shield tunnel projects such as Shanghai M8 line, the model test study of the interaction between the lining structure and soft soil layer of the DOT shield tunnel was carried out. Through the series of orthogonal experiments,the parameters effect of the interaction between the soft soil and the DOT shield lining was investigated to observe the structural internal force response of the DOT shield lining under the action of the soft soil layer .By comparison, it is found that the vertical column in the interval between Ring1 and Ring2 （1.2-2.4 m） can ensure the control of the deformation of the lining to stay in the 3 mm range of the specifications required, and the test results were consistent with the actual deformation results of the whole ring layout of the M8 lining.The reduction coefficient of internal force transmission was from 0.61 to 0.97. Cross-scale comparative analysis of stratum sedimentation and particle migration law was given by u- sing particle image velocimetry PIV2C software and test camera system to compare the field measured data. The results showed that the influence law of the stratum settlement curve from the surface to the lining of the top performance was shown as the ＂U-V-W type＂ change. With the collapse area ratio of 0.85, the technique of PIV can better reveal DOT shield soft soil saddle groove and transient migration law of forming an arch collapse in the DOT tunnel construction process.