The Technology Research Of Control Blasting Shock Absorption For The Urban Shallow Tunnel Wear Under The Existing Buildings

Chongqing is located in the western mountains, the rock of it is hard, the tunnel of Chongqing can use the traditional mining method, the shield method and the TBM method. If use the traditional mining method to construct tunnel in the main urban areas, despite the higher construction efficiency, but that will bring great influence to the adjacent buildings and the surrounding people’s daily life, which is not conducive to the building of a harmonious society. Therefore, in the premise of reducing the city tunnel during the construction of the impact on the surrounding residents daily life as more as possible, to carry out the study of city tunnel construction method can effectively reduce the construction cost, shorten the construction period, and has broad application prospects and better promotion value.In this paper, taking Wulukou station of Chongqing Metro Line 6 based on the project to develop the method research, the application of large span and shallow buried tunnel blasting safety control station, based on the blasting vibration monitoring and numerical simulation analysis method to the station in the surrounding rock under blasting excavation and the dynamic response analysis of blasting vibration of adjacent buildings.Through the field monitoring results and the numerical simulation results compared to study and put forward the analysis and evaluation of the damping effect, put forward reasonable blasting parameters of the project. In this paper, the main research contents and results are as follows:① Based on the large span shallow buried tunnel blasting safety control technology research, parameter method proposed tunnel blasting method under the complex city environment condition based on the blasting effect and blasting vibration evaluation techniques include the monitoring of blasting vibration and numerical simulation technology, put forward the control measure of the blasting shock absorption technology for the large span and shallow buried subway station.②In the structural dynamic calculation analysis and research, combined with the new method the Wulukou station and the actual construction process, analysis the calculation model of the selected blasting parameters and determination of blasting load, then selecte the simulation condition of numerical analysis, the numerical simulation method under the project in this paper.③The results of numerical simulation, the dynamic response rule of the blasting excavation of surrounding rock displacement variation characteristics and surface particle; through the simulation analysis of different excavation step, the dynamic responses of the buildings on the ground under the condition of different excavation step; compare and analysis the site of monitoring results and the numerical simulation results, put forward the method of blasting parameter optimization.④ Analysis and evaluate the shallow depth excavation blasting seismic effect in the construction process of the subway station, according to the monitoring results of blasting parameter optimization lasting vibration, the reasonable blasting parameters and optimization,which can guide the engineering practice and provide a reference for other similar engineering.