文章编号：1004－5422(2021)03－0318－06                                               DOI:10.3969/j.issn.1004-5422.2021.03.016

不同地应力下应力波在节理岩体中传播试验

摘  要：在地应力作用下，应力波在节理岩体中的衰减规律是近些年在深埋地下工程中的热点问题.本研究设计了可同时模拟单条节理和多条节理的组合砂浆试块模型试验，自制地应力加载系统，其尺寸为180 cm×80 cm×25 cm.为避免炸药爆炸应力波与爆生气体难以分离的情况，提出一种电火花震源替代炸药震源激发应力波的方法，分析了应力波在地应力荷载下单条节理和多条平行节理中的传播衰减规律.试验结果表明，当电火花激发电压为2 500 V时，随着地应力从0.5 MPa增加到5.0 MPa，地应力对波传播有一定的抑制作用，应力波在节理岩体中有效波速随地应力的增加而增大，单条节理与多条节理岩体中透射系数都随地应力增加而减小.
关键词：地应力；应力波传播；电火花；节理岩体
中图分类号：TV45;P315.9        文献标识码：A

Experiment of Stress Wave Propagation in Jointed Rock under Different in Situ Stress

Abstract：In the construction of underground engineering in in situ stress areas,the attenuation law of stress wave in jointed rock mass under in situ stress been a hot issue in deep underground engineering in recent years.In the paper,a combined model consisting of multiple cement mortar blocks that can simulate a single joint and multiple joints at the same time was designed,and its dimension was length × width × height = 180 cm × 80 cm × 25 cm.To avoid the difficulty of separating the explosive stress wave from the explosive gas,a method of replacing the explosive-induced stress wave with the ZDF-3 spark source was proposed.The propagation and attenuation law of stress wave in single joint and multiple parallel joints under in situ load was mainly analyzed.The experimental results show that: (a) from 0.5 MPa to 5.0 MPa when the spark excitation voltage is 2500 V; (b) the effective velocity of the stress wave increases with the increase of the in situ stress; (c) the transmission coefficient in jointed rock mass with a single joint and multiple joints decreases with the increase of the in situ stress.