Research on the monitoring early warning system for the foundation pit construction passing through the original subway elevated pile foundation on the basis of information exchange

The research background is the foundation pit excavation of the new metro station which passes through the existing metro elevated pile foundation. By using the finite element analysis method, the numerical simulation of the excavation of the foundation pit is carried out. The supporting structure in the excavation of the foundation pit and the safety of the original subway Viaduct Pile close to the foundation pit are studied. Through the research, the calculation results of the force and displacement deformation of the supporting structure and the original Metro Viaduct Pile in the process of foundation pit excavation are obtained. After comparing the above calculation results with the monitoring values, the reasonable optimization scheme for the support structure is obtained. In addition, through the method of building database, the information of structure attribute between the finite element model and BIM model is exchanged. On this basis, the visual programming method dynamo is introduced, the command flow and some custom nodes are compiled, and the mutual flow of monitoring information and early warning information between the finite element model and BIM model is completed. This realizes the safety control method of subway construction based on BIM Technology, which integrates engineering information, monitoring and early warning.