Abstract: This case study presents a sudden ground collapse at Baishazhou Boulevard in Wuhan city and its emergency remediation. The conventional approaches of underground drainage pipe construction techniques and their induced engineering hazards are also discussed. It is concluded that the SoilMixingWall (SMW) method has an advantage for the open excavation support in the emergency remediation. The SMW construction parameters in the silty soils fed back from the construction observation are also summarized in the paper.

Key words: Underground drainage pipelines, Engineering hazards, road subsidence, Soil-mixing-wall (SMW) method, Remediation measures