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Abstract Taking construction section with center cross diagram(CRD) method in Zhongming tunnel of Nanjing—Anqing passenger dedicated line for example，deformation of surrounding rock and control effect of shallow tunnel with weak interlayer were analyzed by comparing with site measurement in different construction conditions，and the quantitative indices of surrounding rock deformation are established. The results show that deformation of surrounding rock could been controlled effectively during excavation by CRD method，and it could been reduced by employing advanced conduit grouting in surrounding rock of vault；Surrounding rock ranges affected by excavating are 3.0-3.5 times of the tunnel diameter in longitudinal section and about 4.0 times in cross-section，showing spatial effect obviously. The laws of surrounding rock deformation remained basically the same in numerical simulation and site measurement and it was more similar to curve of Panet，and the advance core pre-convergence deformation of excavation face is about 45% of total deformation. The limit value of surface and vault subsidence are 40 and 80 mm respectively，and the limit value of rate and relative subsidence are 5 mm per day and 0.64% in vault.
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Received: 26 May 2013
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2014, Vol. 33 
