The Research Of The Tunnel Excavation Blasting Vibration Impact On The Surface Buildings

With the rapid expansion of China's transport network,when encountered the mountains constructed tunnel,when encountered the rivers constructed bridge,greatly improving the speed of traffic,saving the running time and for China's rapid economic development has laid a good foundation.In recent years,China has accelerated the construction of infrastructure,such as the construction of high-speed railway,urban subway,etc.,it is inevitably to tunnel excavation.Blasting technology has been widely used in the field of tunnel excavation,it has been applied to China's economic construction in various fields,and become one of the important construction methods.The method has brought great economic benefits,but also produced certain harm,so it gets more and more attentions.In this paper,the excavation of a railway tunnel in south central of Shanxi is taken as the research object,based on the combination of numerical simulation and field measurement,the influence of tunnel blasting excavation on surface buildings is studied in detail.It is necessary not only to ensure the safety of buildings,but also to ensure the normal use of high precision instruments stored in buildings.The main contents and conclusions as follows:(1)Combined with the actual engineering of a railway tunnel in south central of Shanxi,the excavation information is extracted according to the actual construction data,the blasting scheme is analyzed and the relevant blasting parameters are collected.Then collated and analyzed the measured results of the field,and obtained the change rule of the measured vibration velocity of each building.(2)According to the actual working conditions and the actual parameters to established three-dimensional numerical calculation model,and simulated the impact of tunnel blasting vibration on surface buildings,extracted and analyzed the simulation results.The variation law of the vibration velocity of each point of the building is analyzed.(3)Comparison of numerical simulation and field test data results,verify theaccuracy of numerical simulation model.Then make a safe decision on the building,and ultimately get the tunnel blasting construction will not cause damage to the building,the same will not affect the normal use of high precision instruments within the building.(4)Summarized and analyzed the blasting vibration control measures,and emphatically studied the variation law of vibration velocity of buildings in different sections,apart from this,this paper also studied the damping effect of different distance,different depth,different width,different length damping ditch.