文档介绍：第 30 卷第 6 期岩石力学与工程学报 Vol. 30 No. 6
2011 年 6 月 Chinese Journal of Rock Mechanics and Engineering June,2011

三维动静组合加载下岩石力学特性试验初探

宫凤强 1,2,李夕兵 1,2,刘希灵 1,2
(1. 中南大学资源与安全工程学院,湖南长沙 410083;2. 中南大学深部金属矿产资源开发与灾害控制湖南省重点实验室,湖南长沙 410083)

摘要:基于对深部岩石承受高地应力并在动力开挖扰动下发生破坏这一问题的科学认识,利用改造的三维霍普金
森动静组合加载试验装置,开展三维动静组合加载下砂岩力学特性试验的初步研究。选取 3 个围压水平(0,5,和
10 MPa)和 3 个典型轴压水平(60,80 和 100 MPa),开展不同应变率下的三维组合加载试验。研究结果表明,当围
压一定,轴压比在 ~ 范围内变化时,砂岩的抗压强度都会随着轴压的增大而逐步减小。当轴压一定,围
压为 5 MPa 时砂岩的抗压强度跟无围压情况下差别不大。但是当围压增大到 10 MPa,砂岩的抗压强度会有较大提
高。本文的研究结果也证明了冲击过程中轴压对砂岩内部的裂纹起催生作用,弱化微元体的承载能力,导致割线
模量降低;围压则可以抑制裂纹的萌生和扩展,强化了微元体的承载能力,使得割线模量会增加。研究结果还表
明,在本文轴压比范围内,当围压一定时,砂岩单位体积释放能会随着轴压的增大而降低,当常规静载轴压比为
~ 时,转化为吸能状态。在三维动静组合加载下,砂岩会呈现出“单锥”压剪破裂形式。
关键词:岩石力学;深部岩石;三维动静组合加载;霍普金森压杆;抗压强度;动态强度
中图分类号:TU 458 文献标识码:A 文章编号:1000–6915(2011)06–1179–12

PRELIMINARY EXPERIMENTAL STUDY OF CHARACTERISTICS OF
ROCK SUBJECTED TO 3D COUPLED STATIC AND DYNAMIC LOADS

, , ,
GONG Fengqiang1 2,LI Xibing1 2,LIU Xiling1 2
(1. School of Resources and Safety Engineering,Central South University,Changsha,Hunan 410083,China;2. Hunan Key
Laboratory of Resources Exploitation and Hazard Control for Deep Metal Mines,Central South University,
Changsha,Hunan 410083,China)

Abstract:Based on the scientific understanding of deep rock under high crustal stress and dynamic excavating
perturbation,the dynamic failure characteristics of sandstone subjected to three-dimensional(3D) coupled static
and dynamic loads are experimentally studied preliminarily with a modified 3D split Hopkinson pressure
bar(SHPB) apparatus. Three levels of confining pressures(0,5 and 10 MPa) and three typical levels of axial
compressions(60,80 and 100 MPa),are designed;and the 3D coupled loads tests are carried out under different
strain rates. The results show that,when the confining pressure is constant,the pressive strength will
decrease when the ratio of pressive stress to pressive ultimate capaci