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The shield tunnel of Nanjing subway line 10 is with two-tracks and is constructed by large diameter slurry balance shield.The section of shield tunneling is in sandy strata of high water pressure.In order to ensure the smooth shield construction, the following methods are used for ground consolidation in the intermediate air shaft: tri-axial deep stirring pile method + high pressure jet grouting pile method + vertical freezing method.According to numerical simulation of ANSYS, when the time of active freezing reaches 7 days, most of the adjacent freezing pipes have been circle-crossing.When the freezing time reaches 30 days, the effective thickness of the freezing wall is 2.2 r.In order to ensure the effect of freezing, the layout of the freezing pipe should be slightly larger than the effective freezing range.This article simulates the whole process of shield tunneling by numerical simulation, including removal of the temporary wall, shield tunneling and so on.The calculation results indicate that the ground consolidation has achieved good results.