Risk Analysis and Evaluation Model Based on Internal Support Structure in Deep Foundation Pit Engineering

The study addresses the pervasive occurrence of safety incidents in deep foundation pit engineering and the suboptimal efficacy of prevailing risk analysis and evaluation methods. It proposes a risk analysis and evaluation model that leverages an internal support structure based on the engineering of a large tipping machine room and a quilted underground operation station. The study establishes the risk analysis and evaluation indexes through the control of pit deformation and internal force, and proposes a higher spline interpolation function method to calculate the bending moment of enclosure wall. Indoor simulation revealed that when six supports were removed from the pit, the risk level of the supporting structure was as high as 0.74, with a risk level of 4. The validation of the project example indicated that the overall risk level of the project was 0.46, corresponding to a risk level of 3. The risk level of the local area was 0.32-0.62, and the risk level of area 3 was 4. Combined with the finite element simulation, it showed that the gap between the risk analysis and evaluation method proposed in the study and the simulation results was only 5.25 mm. The outcomes reveal that load loading has a serious effect on the horizontal displacement of diaphragm walls. The risk analysis and evaluation model based on internal support structure proposed in the study has reliable application value in the construction monitoring of deep foundation pit engineering and has positive significance in improving the efficiency of engineering construction monitoring.