隧道表面爆破地震波的产生机制及传播特征  

Generation mechanism and propagation characteristics of blasting seismic waves on tunnel surface

作　　者：蒙贤忠 周传波[1] 蒋楠[1] 张玉琦 张震 吴迪 MENG Xianzhong;ZHOU Chuanbo;JIANG Nan;ZHANG Yuqi;ZHANG Zhen;WU Di(Faculty of Engineering,China University of Geosciences,Wuhan 430074,Hubei,China;State Key Laboratory of Precision Blasting,Jianghan University,Wuhan 430056,Hubei,China;Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,Hubei,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]江汉大学精细爆破国家重点实验室,湖北武汉430056 [3]中国科学院武汉岩土力学研究所,湖北武汉430071

出　　处：《爆炸与冲击》2024年第2期175-192,共18页Explosion and Shock Waves

基　　金：国家自然科学基金(41972286,42102329)。

摘　　要：为了研究隧道表面爆破地震波的产生机制及传播规律,提出了隧道表面爆破振动平面应变理论模型,得到了隧道表面爆破振动场积分形式解;以龙南隧道爆破工程为背景,建立了有限元数值模型,通过现场测试验证了数值模拟与理论解答的准确性;提出了基于高分辨率Radon变换的隧道爆破地震波波场分离方法,结合理论解析与数值模拟得到了P波、S波、R波的传播特征,最后综合理论结果与波场分离结果提出了隧道爆破地震波作用分区。结果表明:隧道爆破产生P波、S波,R波在自由面迅速发育,3类波呈现指数衰减特征,S波衰减快于P波快于R波。随着爆心距的增大,垂直方向主要成分由S波转变为R波,水平方向主要成分由S波转变为P波,P波转变为R波。Ⅳ级围岩工况下,隧道爆破地震波作用分区为:隧道轴向距掌子面0~6.44 m为爆破近区,主导波型为水平S波;6.44~21.23 m为爆破中区,主导波型为水平P波;21.23 m外为爆破远区,主导波型为垂直R波。爆破分区分界点与单段最大药量呈线性关系,可通过爆破药量得到隧道爆破分区位置,用于隧道安全稳定性分析。In tunnel blasting and excavation engineering,blasting vibration is the main harmful effect affecting safety and stability.In order to investigate the generation mechanism and propagation patterns of seismic waves resulting from blasting in tunnel contexts,a theoretical model based on plane strain conditions is developed to depict the tunnel surface vibration caused by blasting.Then,a solution in integral form is derived to describe the surface vibration field generated from tunnel blasting.Utilizing the Longnan tunnel blasting project as a contextual backdrop,a finite element numerical model is established to recreate the conditions.This allows for the validation of both the numerical simulations and theoretical solutions through onsite tests.To elucidate the propagation characteristics of distinct types of seismic waves resulting from blasting,a method adopting a high-resolution Radon transform approach is devised to separate the tunnel blasting seismic wave field.By combining theoretical analysis with numerical simulation,the propagation characteristics of P-waves,S-waves,and R-waves are ascertained.Further,by synthesizing theoretical results and wave field separation results,the seismic wave action partition of tunnel blasting is proposed.The results show that tunnel blasting excites P-waves and S-waves,while R-waves surge swiftly upon encountering the free surface.The triad of wave categories displays exponential attenuation tendencies,with S-waves demonstrating a swifter decay rate than P-waves,and P-waves outpacing R-waves in this regard.In terms of directional dominance,the main component in the vertical direction changes from S-wave to R-wave,and the main component in the horizontal direction changes from S-wave to P-wave,and then P-wave changes to R-wave.A detailed spatial analysis further elucidates this scenario.Under the working conditions of gradeⅣsurrounding rock,the seismic wave action zone of tunnel blasting is as follows:the area of 0-6.44 m away from the tunnel axis to the tunnel face is rega

关 键 词：爆破地震波 隧道爆破 产生机制 传播特征 理论解析 

分 类 号：O382[理学—流体力学]