高地应力隧道聚能爆破裂纹扩展规律研究  

Research on Crack Propagation Law of Concentrated Energy Blasting in High Ground Stress Tunnel

作　　者：李旭东 LI Xudong(CRCC Harbour and Channel Engineering Bureau Group Co.Ltd.,Chongqing 400025,China)

机构地区：[1]中国铁建港航局集团有限公司,重庆400025

出　　处：《铁道建筑技术》2024年第10期27-31,共5页Railway Construction Technology

基　　金：中国铁建港航局集团有限公司科技研究开发计划项目(2019-A05)。

摘　　要：随岩体深度增加,高地应力环境对隧道及地下工程爆破施工影响随之增加。目前隧道爆破未能充分利用高地应力条件与炸药爆炸产生的能量,开展高地应力下隧道爆破裂纹扩展机理与能量高效利用调控方法对节省施工成本意义重大。理论研究隧道高地应力静态分布特征及应力动态演化规律,对高地应力下单孔及双孔聚能爆破进行数值模拟分析,发现主裂纹长度随应力值增加呈指数性衰减,随侧压系数增加呈线性增长;当最大主应力达40 MPa时,随聚能方向与最大主应力方向夹角增加,孔间裂隙贯通性逐渐变差。现场应用聚能管装置完成聚能爆破,通过爆破测振仪监测现场振速,对比常规钻爆法爆破中峰值振速评估聚能爆破效果,为后续工程应用提供参考。As the depth of the rock mass increases,the impact of the high ground stress environment on tunnel and underground engineering blasting construction is also increasing.However,the high ground stress conditions and the energy generated by blasting of explosives have not been fully utilized.Therefore,studying the mechanism of crack propagation in tunnel blasting under high ground stress and efficient energy utilization control methods is of great guiding significance for saving construction costs.This article theoretically studied the static distribution characteristics and dynamic evolution law of high ground stress in tunnels.Numerical simulation analysis was conducted on single hole and double hole concentrated energy blasting under high ground stress.It was found that the length of the main crack decays exponentially with the increase of stress value and increases linearly with the increase of lateral pressure coefficient.When the maximum principal stress reaches 40 MPa,as the angle between the direction of energy accumulation and the direction of maximum principal stress increases,the permeability of inter hole cracks gradually deteriorates.The energy gathering tube device is applied on site to complete energy gathering blasting.The on-site vibration velocity data is monitored through blasting vibration meter to evaluate the effect of energy gathering blasting by comparing the peak vibration velocity in conventional drilling and blasting methods,which provides reference for subsequent engineering applications.

关 键 词：隧道爆破 高地应力 聚能管 裂纹扩展 数值分析 

分 类 号：U455.6[建筑科学—桥梁与隧道工程]