EFFECT OF SUBWAY FOUNDATION PIT DEWATERING ON SUBGRADE SETTLEMENT OF COMPOSITE FOUNDATION

摘要

Additional settlements of the construction finished CFG composite foundation are caused by subway foundation pit dewatering.Based on the monitoring data of magnetic ring subsidence in deep layer,the settlement deformation law of composite foundation during dewatering was studied in this paper.Results showed that the influence depth of embankment filling and subway foundation pit dewatering was 45 meters underground,which was two times of pile length from the pile bottom.The CFG piles were under the state of positive friction during the embankment filling,and were under the state of negative friction during subway foundation pit dewatering period.The soil between CFG composite piles was significantly more influenced by subway foundation pit dewatering than the CFG piles.