Study On The Impact Of Urban Tunnel Blasting Excavation On The Vibration Of Adjacent Brick-concrete Buildings

In recent years,China's urban construction has developed vigorously,and many cities have serious traffic pressure.Therefore,in order to alleviate the pressure,vigorously develop urban rail transit construction.In the construction process of urban subway tunnels,compared with other construction methods,drilling and blasting construction has always been the most widely used method.The drilling and blasting method has good economic benefits,and at the same time,it will cause a certain degree of damage to the surface structures(structures),and even endanger the safety of the people and property of the ground residents.In order to study the impact of blasting excavation of urban tunnels on nearby buildings(structures),this paper relies on a subway project in XinJiang,through the use of theoretical analysis,numerical simulation,on-site monitoring and other methods to affect the building structure affected by blasting vibration,research and analysis of the changes in the dynamic response characteristic values(displacement,vibration speed,vibration acceleration,etc.)of structures under blasting vibration,the purpose is to summarize the dynamic response of tunnel blasting vibration to buildings(structures),analyze and judge the safety of buildings(structures),and to guide subsequent similar projects,which can be safely and orderly constructed.The following is the main research content and results of this article:(1)The mechanism of blasting vibration generation,the classification of blasting vibration waves and the influencing factors of blasting vibration intensity were elaborated,and the dynamic response of building structures under blasting vibration and the factors affecting the destruction of building structures were analyzed.(2)The blasting vibration characteristic value and time history analysis method are introduced in detail.Using MIDAS/GTS finite element software,the model soil,building structure,blasting and other parameters are selected and the boundary conditions and blasting load application method are determined.Simulation method.(3)Through the MIDAS/GTS finite element software,the time history dynamic analysis method is used to simulate the actual working conditions,the numerical simulation results are compared with the actual monitoring data,and the error between the numerical simulation and the actual working conditions is analyzed.Simulate and calculate the dynamic response of buildings under blasting construction under four working conditions,analyze and summarize the response rules of vibration displacement,vibration speed and vibration acceleration of buildings under four working conditions,and obtain various dynamic response indicators of building structure through analysis(Vibration speed,acceleration,displacement)all meet the relevant standards.(4)The method of optimizing blasting parameters and vibration damping measures are proposed,and the optimized blasting parameters and vibration damping measures are simulated and analyzed using MIDAS/GTS to guide the subsequent construction and provide references for other similar projects.