| With the rapid development of traffic construction,the past single-hole two-lane tunnel or single-hole three-lane tunnel have been unable to meet people's production and living needs,and a large number of double-hole tunnels need to be built.Therefore,how to better reduce the impact of blasting vibration of surrounding rock of adjacent tunnel during tunnel blasting has become a research direction.By studying the influence of different factors on the surrounding rock blasting vibration of adjacent tunnels,it is of great practical significance to improve the design scheme and construction process to reduce the surrounding rock damage and improve construction safety.In order to study the influencing factors of the blasting vibration of the surrounding tunnel in the tunnel,in this paper,through the combination of on-site monitoring and numerical simulation,the effects of tunnel surrounding rock properties,adjacent tunnel clearance and vehicle liaison channel on the blasting vibration of adjacent tunnel surrounding rock are analyzed.The influence of the liaison channel on the blasting vibration of the surrounding rock of adjacent tunnels.The main work and results of this paper are as follows:1.Based on the analysis of on-site monitoring data,during the tunnel blasting construction,the blasting vibration wave between each segment will have a superposition effect,which has a great influence on the surrounding rock of the tunnel,and the influence on the surrounding rock of the adjacent tunnel is negligible,so the blasting vibration speed of the adjacent tunnel surrounding rock has a better reference significance for improving the blasting parameters.2.Based on the analysis of on-site monitoring data,during the construction of the tunnel blasting,the maximum blasting vibration velocity of the surrounding rock of preceding tunnel increases with the increase of the single-stage charge.Using the Sadowski formula to fit the maximum vibration velocity in the presence or absence of the vehicle liaison channel,the equation of the fitted curve is obtained (?).The field coefficient K=7.63 and the attenuation coefficient?=0.73 in the case of the adjacent tunnel without vehicle liaison channel;the field coefficient K=44.84 and the attenuation coefficient?=1.32 in the case of the adjacent tunnel with vehicle liaison channel.The vehicle liaison channel has increased the impact of the construction of the rear tunnel on the blasting vibration of the surrounding rock of the preceding tunnel.3.Based on the geometric model of the adjacent tunnel without vehicle liaison channel,the influence of tunnel surrounding rock properties and adjacent tunnel clearance blasting vibration velocity of the surrounding tunnel surrounding rock is analyzed.The results show that the most dangerous mass of the first tunnel is located at the arch of the blasting surface;the greater the elastic modulus of the surrounding rock of the tunnel,the smaller the impact of the blasting vibration on the surrounding rock of the adjacent tunnel;Using the Sadowski formula to fit the maximum vibration velocity in the presence or absence of the vehicle liaison channel,the equation of the fitted curve is obtained (?).The field coefficient K=8.73 and the attenuation coefficient?=0.83 in the case of the adjacent tunnel without vehicle liaison channel,the vibration range of the blasting of the tunnel in the trailing tunnel is 4 times the tunnel hole diameter.4.Based on the geometric model of the adjacent tunnel with vehicle liaison channel,the influence of the vehicle liaison channel blasting vibration velocity of the surrounding tunnel surrounding rock is analyzed.The results show that when the distance between the vehicle liaison channel and the back tunnel face is 5 times of the tunnel hole diameter,the influence of the vehicular vibration on the surrounding rock of adjacent preceding tunnel caused by the detonation of the back face of the rear tunnel is negligible;the vehicle liaison channel perpendicular to the tunneling direction The blasting vibration of surrounding rock of adjacent tunnel has the greatest influence. |
PDF Full Text Request