The Nanjing subway section between Zhujiang Road station and Gulou station passes through many ground buildings and dense underground pipes in soft-flowing mucky silty clay ground. The stratum is of high compressibility

low intensity

easy creeping

and no self-stability. The synthetical measure is adopted in this project

such as large pipe shed and small tremie as advance support and deep hole grouting at the work face

bench excavation and steel surpport

steel mesh and shotcrete support. In order to realize scientific decision and safety construction

calculation simulation is carried out according to the actual working condition to predict the surface subsidence. At the same time

subsidence monitoring is done during construction. The safety and smoothness of the tunnel construction is assured and the buildings are sound without any destruction.