【摘要】 结合福州国际机场高速公路鹤上三车道小净距隧道工程实践,对小净距隧道中间岩柱在爆破荷载作用下的振动响应进行相关监测,分析振动波在不同级别围岩、不同监测位置的传播及分布规律。研究结果表明:隧道中间岩柱边墙部位振动速度大于拱脚部位,且随着围岩质量提高,振动速度差别逐渐减小;最大振动速度出现在迎爆侧边墙测点的径向方向,可将其作为爆破振动的控制速度;当隧道净距为6 m左右(约0.35B)时,爆破振动对中间岩柱的影响范围为爆破面前后10～20 m,且随围岩质量提高,影响范围相应减小;爆破面前方中间岩柱受爆破振动影响要大于爆破面后方岩体,施工中宜加强该部位监测;同时,宜严格控制爆破总药量和单段最大药量,且分段爆破时,爆破段差应不小于100 ms。该研究结论可为类似条件下小净距隧道的爆破控制和现场监测提供借鉴与参考。更多还原

【Abstract】 According to the construction of Heshang three-lane tunnels with small clear space in Fuzhou international airport highway,the monitoring of blasting vibration was carried out.Based on measured data,the propagation and distribution characteristics of vibration waves in the rock mass were analyzed.Some conclusions have been drawn.Vibration speed at tunnel wall is greater than that at the foot of the wall;and the better the rock mass quality is,the less differences the vibration speeds at the two places are.The maximum vibration speed occurs at the radial direction of tunnel wall facing the blasting side,which can be regarded as the controlling vibration speed.When the clear distance of two tunnels is 6 m(about 0.35B),the disturbance range of blasting vibration to inter-space rock is 10–20 m apart from the blasting working face.The better the quality of rock mass is,the less the disturbance range is.And the blasting has more influences on the rock in front of the blasting face than that behind of the blasting face.In addition,the total explosive volume should be strictly controlled and decreased,as well as the single segment,and the blasting segments interval time should be greater than 100 ms.The experience and conclusions presented can be referred in the blasting controlling and site monitoring of similar tunnels.更多还原