The Impact Of Near-distance Blasting On Adjacent Buildings

In recent years,drilling and blasting construction technology has been widely used in the engineering field and has achieved good economic and social benefits.However,this technology has also had a lot of negative effects while contributing to the development of the national economy.The blasting excavation caused by the blasting and blasting construction technology has caused the vibration effect of the adjacent buildings to have not been well controlled.Therefore,to explore the impact of blasting vibrations on neighboring buildings,and to take effective measures to ensure that the construction is carried out quickly and safely,minimizing the damage caused by blasting vibrations.This article relies on the construction of Dalunshan Tunnel at Baiyun Avenue(Tongnan Road-Tongandong Road Section)of Xiamen City,the material parameters of numerical simulation are determined by consulting the design information and blasting construction scheme,the influence of blasting on the adjacent building structure is studied and the corresponding measures to reduce the influence are put forward.The main content of this article is as follows:(1)According to the construction drawings of Baiyun Road(tongnan highway and tongan east highway section),the distance between the buildings with different structure types in the explosion zone is determined,and according to the allowable vibration velocity of the blasting safety regulations,the maximum segment charge of buildings of different structural types at the corresponding distance from the blasting site is calculated.(2)The blasting vibration monitoring is carried out for the slope of the pre-blasting of the exit subgrade section of the Dalun mountain tunnel and the adjacent water tank,four monitoring points were assigned to the safety monitoring,two of them are arranged on the slope of the earth and stone,the other two measuring points are arranged at the end of the sink,and one is arranged in the middle part of the sink.Through the field monitoring,it was found that the vibration velocity of the structure was not exceeded when the blasting was calculated.(3)Using the LS-DYNA module of ANSYS of large general finite element software,the whole finite element model of rock-structure was established,the model analysis of the four-layer reinforced concrete frame structure is carried out,and the natural frequency and vibration pattern of the structure are obtained.The whole finite element model of explosive source-rock-building is established,the influence of the detonation distance and the depth of the explosive buried depth on the measuring point velocity of the building is analyzed.(4)From the Angle of controlling blasting energy transfer,two engineering measures for reducing blasting vibration are proposed,respectively,the excavation damping ditch and the use of millisecond delay blasting technology.using the method of single hole blasting vibration loading to established the whole finite element model of explosive source-structure,study the influence of the excavation damping ditch in different position,and the effects of different depth and width of danping ditch on blasting vibration were analyzed.using the method of double hole blasting vibration loading to established the whole finite element model of explosive source-structure,study the effect of millisecond delay blasting and the analysis of the differential interval of 0ms/m,3ms/m,Sms/m and 7ms/m of the four type,the blasting vibration wave and the change of the peak data,and get the optimal millisecond delay interval is 5ms/m,used to guide the engineering practice.