The Research On Road Surface Of Shallow Buried Tunnel Blasting Vibration

Whatever field mountain shallow tunnel or subway must be special processing during design and construction.we need pay attention to it when tunnels pass directly underneath some important structure.So, It’s important to study the influence and disaster control to the structure of shallow tunnel Blasting seismic effect.The paper’s background is studying the Fairy cave tunnel。The tunnel, with the tunnel exit locats on mountain slope, goes through shallow-buried section, the321national road and Houses community.These two blasting methods of tunnel excavation were designed depend on the engineering geology condition and the requirements of Safety regulations for blasting practices.At the same time, I made dozens of Blasting vibration test which satisfied the requirements of Safety regulations for blasting practices.Considering the field test statistics, It can draw vibration frequency spectrum characteristics of various working conditions, and the attenuation law of vibration velocity depend on the elevation difference and tunnel hole.Although vibration velocity attenuation do not follow the previous related attenuation law, it changes by distance.Only considering the effect of tunnel excavation hole, if there is no tunnel hole where blasting seismic wave spreads, the velocity increases with the decrease of distance; if there is tunnel hole where blasting seismic wave spread, the velocity increases then decreases with the decrease of distance.Considering the effect of tunnel excavation hole and different elevation, if there is no tunnel hole where blasting seismic wave spreads, the velocity increases with the decrease of distance; if there is tunnel hole where blasting seismic wave spread, the relationship between the velocity and distance is applied to sine function.Safety regulations for blasting practices doesn’t includes road safety standards of blasting in the paper’s background. It can deduce the damaging velocity of road surface with blasting seismic wave in different raw angle. Ⅰ carried on the example analysis of C30concrete pavement, and got some conclusions:Transverse wave takes control to the pavement damage.It concludes that the limit velocity as Safe speed criterion the C30concrete pavement is the vs(τ) of0.1442m/s which doesn’t damage the pavement.