The Chinese Journal of Nonferrous Metals
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|第14卷 第2期 总第83期 2017年2月|
(中南大学 土木工程学院，湖南 长沙 410075)
摘 要: 以广东汕湛高速公路水墩隧道为工程背景，采用现场实测和数值模拟计算方法，研究薄基岩顶板隧道在掏槽爆破荷载作用下掌子面附近围岩的振动特性。研究结果表明：在沿隧道纵向上，在掌子面后方约4 m范围内的隧道拱顶围岩振速处于较高水平，需加强支护并重点监测；在掌子面平面上，由于左高右低倾斜岩层界面的存在，使掌子面附近围岩右侧(基岩顶板较薄侧)振速整体上比左侧(基岩顶板较厚侧)大，右侧振速衰减速度整体上比左侧慢，掌子面右上方附近围岩为薄弱区域，应重点防护。
（School of Civil Engineering, Central South University, Changsha 410075, China）
Abstract:Taking the Shuidun tunnel on Guangdong Shan-Zhan Expressway as an example, the vibration characteristics of surrounding rock with thin roof bedrock layer under the blasting load were analyzed by means of field measurement and numerical simulation methods. The results show that: along the longitudinal direction of the tunnel, within a range of 4 m tunnel excavation area behind the tunnel face, the vibrating velocity of surrounding rock near the tunnel arch crown tend to the maximum, and these sections should be intensify observation and take certain reinforcing measures. In the plane of the tunnel face, the existence of rock interface that inclined to the right side has lead to the vibrating velocity in the right side (with thinner bedrock roof) bigger in general than that in the left side (with thicker bedrock roof), and the attenuation rate in the right slower in general than that in the left side. Moreover, the upper right side of the rock around the tunnel face is the weak area which should be given prevention.
Key words: tunnel; blasting; thin bedrock roof; numerical simulation; vibration characteristic