Influence Of Utility Tunnel Jacking Construction On Surface And Structure Deformation And Performance Test Of Drag Reduction Mud

With the rapid growth of China's national economy,the development and utilization of urban underground space in many municipal projects has become the focus of attention.Compared with the traditional foundation pit excavation construction method,pipe jacking construction technology as a kind of The typical non-excavation technology is more and more applied because of its unique advantages.However,the pipe jacking construction will affect the surrounding soil more or less.If the soil is too deformed,it will affect If the surrounding buildings(structures)are not given high priority,they may even endanger people's property and life safety.Therefore,studying the impact of pipe jacking construction on the surrounding environment and controlling the damage caused by pipe jacking construction to adjacent buildings(structures)is still an important issue in the future pipe jacking construction process.Based on the comprehensive pipe gallery project of Heping Road,Heping Road,Qingshan District,Wuhan,this paper analyzes the surrounding soil caused by pipe jacking construction through the ratio test of indoor drag reduction mud,the actual measurement analysis of deformation of pipe jacking construction and finite element numerical simulation.And the deformation mechanism of the structure,the calculation method of the surface deformation and the performance optimization of the drag reduction mud have been comprehensively studied.The main research contents and results include:1.Optimization experiment of drag reduction mud ratio.In this paper,the raw materials of the drag reduction mud and the molecular structure of related materials were studied.The effects of various raw materials on the performance of the drag reduction mud were designed and tested,and a better performance of drag reduction mud was proposed.The ratio of each raw material in the ratio is 8% of bentonite,0.1% of CMC,0.3% of soda ash,0.05% of PAM,0.1% of potassium humate,and 91.45% of water.2.The actual measurement of the surrounding soil and structure deformation caused by utility tunnel jacking construction is carried out.The main contents of the site survey include surface settlement,pipeline settlement,horizontal deformation monitoring of deep soil,building settlement and bridge pier deformation.The vertical and horizontal surface settlement above the axis of the jacking pipe caused by utility tunnel jacking construction and the deep displacement of the soil were analyzed.3.The three-dimensional finite element numerical simulation of the deformation of surrounding soil and structures caused by utility tunnel jacking construction was carried out by MIDAS/GTS software.The distribution law of vertical and horizontal surface settlement above the axis of the jacking pipe is studied,and the simulated ground deformation is compared with the monitoring data.It is found that the simulated calculated value is in good agreement with the actual monitored value.In addition,the contribution of the width and thickness of the MJS jet grouting pile to the influence of the utility tunnel jacking construction on the pier is analyzed.