Research On Construction Blasting Vibration Effects And Testing Technology Of Mountain-adjacent Tunnel

Abstract:It is the mountain-adjacent tunnel excavation by blasting which can have affect on the stability of side slope as well as the people or structure’s safety around it. On this condition, how can both reduce the harm of blasting vibration and ensure construction progress, has become an important issue that must be solved by the current tunneling territories. This article, which relies on the background of Si-feng mountain tunnel and researches construction blasting vibration effects and blasting vibration testing technology of the mountain-adjacent tunnel by using three methods, including numerical simulation, theoretical analyses and field tests, has achieved the following results:1. Based on numerical simulation, peak particle vibration velocity has been calculated from the surface of space distribution and time history, and the surface particle vibration velocity distribution from the perspective of space and time respectively is revealed.2. There comes a study near the tunnel blasting vibration effects by using numerical simulation methods; it determines the degree of damage in slope rock mass by using vibration speed thresholds criteria, which relies on the correlation between particle vibration velocity and the damage degree of rock mass; it can analyze the affect of blasting vibration on the house by the safety regulations for blasting and it can also explore the reflections of people in different locations on blasting vibration.3. It can be summed up that there are laws for particle vibration velocity in different positions of the tunnel and surface, and it proved the amplification effect of particle vibration velocity in slope elevation and compared the prediction effects of peak vibration velocity by the formula method and BP neural network.4. According to the phenomenon of hollow effect of vibration in tunneling blasting, it put forward the significant coefficient of hollow effect which is a quantitative index that used for the characterization of hollow effect degree of distinctiveness; it also revealed the law that hollow effect variation of the vertical and horizontal along the tunnel as well as the influence law of hollow effect affected by maximum of dosage in single segment, the area of tunnel section and the shape of tunnel section.5. Combined with the vibration velocity distribution, a reasonable blasting vibration test plan of Si-feng mountain tunnel was made.