Based on the dynamic characteristics of "ground-environment-construction disturbance" and the statistical analysis of typical safety accidents in the construction of urban underground engineering, this paper points out that the essence of safety accidents in urban underground engineering is the instability and deformation caused by construction, and that controlling ground deformation is the key to safety accident prevention. Considering the structural characteristics of the urban complex stratum, it is suggested that the ground deformation under the influence of the engineering should be considered from three aspects:deformation of ground material, stability of mesoscopic structural layer, and environment inducement. More scientific predictions for complex ground deformation can be made from these three aspects. This paper puts forward the contents of security risk assessment on buildings (structures) and a working procedure for safety risk control of urban underground engineering construction, significantly promoting the control level of construction.

urban underground engineering  /  safety accidents  /  complex stratum  /  ground deformation  /  dynamic process control