The control of micro deformation of adjacent buildings during the construction of deep foundation pits in weak strata is one of the challenges in the geotechnical field. Taking the construction project of subway deep foundation pit of adjacent buildings in soft ground in Hangzhou as an example, this paper introduced the micro deformation control technologies such as the reinforcement technology of underground continuous wall trough wall, sleeve valve pipe grouting reinforcement technology, servo steel support system, and the reinforcement and excavation technology of underground middle wall, and analyzed the deformation characteristics and the effect of micro deformation control technology in the construction of deep foundation pit of adjacent buildings in soft ground. The results indicate that the sleeve valve pipe grouting reinforcement technology reduces the impact of construction on the surrounding building group and suppresses its deformation; the deformation of the enclosure structure and surrounding deformation can be suppressed through slot wall reinforcement technology, and the quality of the enclosure structure has been improved; the servo steel support system effectively suppresses the deformation of the enclosure structure and reduces the impact of construction on the surrounding area; cross wall and block excavation technology suppresses building deformation and weakens the impact of spatiotemporal effects. In the end, the surrounding buildings of the deep foundation pit basically achieved the goal of "micro deformation”.

urban rail transit  /  soft ground  /  building clusters  /  subway deep foundation pit  /  micro deformation  /  control technology