摘要
针对硬岩爆破开挖工程,基于岩石爆破损伤理论和应力波理论,得到与纵波波速相关的硬岩破裂判据,给出了工程中确定爆破破裂范围的方法.在硬岩隧洞开挖后的横断面布置垂直断面轮廓线的声波孔,利用超声波仪器在声波孔内开展纵波波速测试,由测试得到声波孔内各测点的纵波波速,当爆破后的纵波波速相对爆破前的数值下降超过15%时,可判断该部位处于爆破破裂区内,从而得到洞壁的爆破破裂深度.研究结果表明,隧道围岩的爆破破裂深度为0.6~1.0m,大约为隧洞横断面半径的9.4%~15.7%.爆破破裂范围不大,在安全允许范围内.
Aiming at the blasting excavation of hard rock, the criterion to determine rock fracture relating to the longitudinal wave velocity and the method to determine the blasting fracture in the blasting excavation were proposed based on rock blasting damage mechanics and stress wave theory. Using ultrasonic Instrumentation, acoustic velocity tests were conducted to obtain the longitudinal wave velocity in the holes drilled in the surrounding rock of the cross section of hard-rock tunnel. If the longitudinal wave velocity of the test points obtained after blasting declines more than 15% against that obtained in the same points before blasting, these test points are judged in the blasting fracture zone, and thereby the fracture depth surrounding the tunnel can be measured. The results show that, the fracture depth surrounding the tunnel is 0.6~1.0m, 9.4%~15.7% of the length of the tunnel radius. The blasting fracture zone is not lager that it is under control.
作者
张逵
ZHANG Kui(Hunan Communications Survey, Design & Consultation CO.,LTD, Changsha 410075, China)
出处
《湖南理工学院学报（自然科学版）》
CAS
2019年第2期61-66,共6页
Journal of Hunan Institute of Science and Technology(Natural Sciences)
关键词
岩石力学
损伤
爆破
钻孔声波波速试验
破裂
rock mechanics
damage
blasting
acoustic velocity test conducted in the drilled hole
fracture
