Abstract：To study the influences on the earth pressure and ground settlement when the shield tunnel passes through the adjacent underground retaining structures, a self-designed test device is developed, and 15 model tests are carried out taking into account the ratios of tunnel depth to width, side limit width and excavation distance. In the tests, the stratum loss is simulated using the trapdoor settlement. The earth pressures of retaining structures are measured using 18 cantilever load gauges. The particle image velocimetry technique is used to measure the surface settlement. The variations of earth pressure and distribution of surface settlement during excavation under lateral confinement conditions are analyzed. The results show that the earth pressure at the bottom of retaining wall decreases sharply and then increases at a turning point with a certain height when the shield tunnel passes through the adjacent underground retaining structures. The smaller the ratio of depth to width of tunnel, the larger the decrement of the earth pressure at the bottom and the higher the turning point, and the larger the maximum displacement of surface settlement. The larger the ratio of tunnel depth to lateral limit width, the larger the reduction range of earth pressure, and the larger the maximum ground settlement. The greater the ratio of tunnel depth to distance, the greater the influences on earth pressure of retaining structures, and the greater the maximum ground settlement. Two correction coefficients, the maximum surface subsidence C1 and the correction coefficient of settlement trough C2, are introduced, and the Peck’s settlement prediction equation is modified. The predictions show good agreement with the measured values of model tests.
 JENCK O, DIAS D.3D-finite difference analysis of the interaction between concrete building and shallow tunnelling[J]. Géotechnique, 2004, 54(8): 519-528.  杨海鹏, 梁青槐. 隧道开挖对周围建筑物造成的损害及治理措施[J]. 华北科技学院学报, 2005(2): 29-34. (YANG Hai-peng, LIANG Qing-kui.Damage and treatment of adjacent buildings caused by tunnel excavation[J]. Journal of North China Institute of Science and Technology, 2005(2): 29-34. (in Chinese))  朱育才, 林志, 石波. 隧道扩建对地面建筑物的影响分析[J]. 重庆交通大学学报, 2011, 13(5): 938-942. (ZHU Yu-cai, LIN Zhi, SHI Bo.On influence of tunnel expansion on the ground buildings[J]. Journal of Chongqing Jiaotong University, 2011, 13(5): 938-942. (in Chinese))  刘松玉, 李洪江, 童立元, 等. 地下工程开挖卸荷既有桩基承载响应物理模拟及新进展[J]. 岩土工程学报, 2019, 41(7): 1329-1338. (LIU Song-yu, LI Hong-jiang, TONG Li-yuan, et al.Model tests and new progress of pile response due to underground excavations[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(7): 1329-1338. (in Chinese))  张冬梅, 黄宏伟, 王箭明. 盾构隧道施工对邻近深基坑开挖影响的三维有限元分析[J]. 现代隧道技术, 2001, 38(1): 26-30. (ZHANG Dong-mei, HUANG Hong-wei, WANG Jian-ming.Analysis of the influence of shield tummeling on adiacent deep exacvation[J]. Modern Tunnelling Technology, 2001, 38(1): 26-30. (in Chinese))  矫伟刚. 盾构推进对在建地铁风井或车站结构的影响研究[D]. 北京: 中国矿业大学, 2012. (QIAO Wei-gang.Reaserch on the Influence to the Structures of Ventilation Shafts or Mefro Satation by TBM Constuction[D]. Beijing: China University of Mining and Technology, 2012. (in Chinese))  PECK R B. Deep excavations and tunneling in soft ground[C]// Proceedings of the 7th International Conference of Soil Mechanics & Foundation Engineering, 1969, Mexico: 225-290.  ROWE R K, LO K Y, KACK G J.A method of estimating surface settlement above tunnels constructed in soft ground[J]. Canadian Geotechnical Journal, 2011, 20(1): 11-22.  ATTEWELL P B, WOODMAN J P.Predicting the dynamics of ground settlement and its derivatives caused by tunneling in soil[J]. Ground Engineering, 1982, 15(8): 13-20.  刘建航, 侯学渊. 盾构法隧道[M]. 北京: 中国铁道出版社, 1991. (LIU Jian-hang, HOU Xue-yuan.Tunnel Excavation With Shield Method[M]. Beijing: China Railway Publishing House, 1991. (in Chinese))  TERZAGHI K.Stress distribution in dry and in saturated sand above a yielding trap-door[C]// Proceedings of 1st ICSMFE. 1936: 35-39.  WHITE D J, TAKE W A, BOLTON M D.Soil deformation measurement using particle image velocimetry (PIV) and photogrammetry[J]. Géotechnique, 2003, 53(7): 619-631.  芮瑞, 张龙, 孙义, 等. 桩承式路堤土拱演化的二维钢棒相似土模型试验[J]. 中国公路学报, 2017, 30(10): 8-16. (RUI Rui, ZHANG Long, SUN Yi, et al.2D model tests of soil arching evolution in piled embankments using steel rod analogical soil[J]. China Journal of Highway and Transport, 2017, 30(10): 8-16. (in Chinese))  徐路畅, 芮瑞, 张龙, 等. 基于Trapdoor试验的双线隧道地表沉降预测公式探讨[J]. 岩土工程学报, 2017, 39(8): 1470-1476. (XU Lu-chang, RUI Rui, ZHANG Long, et al.Prediction formula for surface settlement in double-line tunnel based on trapdoor tests[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(8): 1470-1476. (in Chinese))  O’REILLY M P, NEW B M. Settlements above tunnels in the United Kingdom: their magnitude and prediction[C]// Proceedings of Tunnelling 82, 1982, London: 173-181.  JAKY J.The coefficient of earth pressure at rest[J]. Journal of the Society of Hungarian Architects and Engineers, 1944, 78(22): 355-358.  RUI R, ZHAI Y X, HAN J, et al. Deformations in trapdoor tests and piled embankments[J]. Geosynthetics International, 2019.https://doi.org/10.1680/ jgein.19.00014.  SPERL M.Experiments on corn pressure in silo cells-translation and comment of Janssen's paper from 1895[J]. Granular Matter, 2006, 8(2): 59-65.