动载荷下岩石起裂与裂纹扩展的声发射特性研究

项目名称： 动载荷下岩石起裂与裂纹扩展的声发射特性研究

项目编号： No.51204206

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 冶金与矿业学科

项目作者： 刘希灵

作者单位： 中南大学

项目金额： 25万元

中文摘要： 本项目紧密围绕动载荷下岩石的声发射特性，基于SHPB系统开展冲击试验研究，旨在探讨中、高应变率冲击压缩荷载下岩石起裂和裂纹扩展的声发射特性及规律。项目以冲击动力学和断裂动力学理论、LS-DYNA动力分析软件、小波理论、分形理论等多种理论和分析方法为手段，找出岩石破裂产生的信号和应力波在岩石中传播时产生信号的特征，并对这两种信号进行分离；基于信号分离的研究，选取两种信号合理的参数以适当的方式结合形成评价冲击荷载对岩石破碎程度的指标；利用静压实验机和杆径分别为22mm、36mm、50mm、75mm的SHPB系统，对不同岩样进行加载速率由低到高的声发射实验，揭示岩石声发射活动随加载速率变化的规律。本项目的探讨不仅完善了岩石在不同加载速率下的声发射实验研究，为频繁动载荷作用环境下的声发射监测提供理论依据，而且为深入认识动载荷下岩石裂纹扩展及破坏机理提供研究基础。

中文关键词： 声发射；岩石动力学；霍普金森压杆；动态破裂机理；

英文摘要： The researches of this project focus on acoustic emission characteristics of rock under dynamic loading. The experimental study will be conducted on SHPB system in order to discuss acoustic emission characteristics and laws of rock crack initiation and propagation under impact compression loads with midum and high strain rates. Impact dynamics and fracture dynamics, LS-DYNA dynamic analysis software, wavelet theory, fractal theory was chosed to identify the characteristics of signals produced by fracturing and stress wave propagating in rock, and then to separate those two signals; based on the signal separation research, the reasonable parameters of those two signals can be selected to properly form an evaluation index for fragmentation degree of rock under impact loading; static loading machine and SHPB systems with 22mm, 36mm, 50mm, 75mm bar diameter which can achieve different strain rates from low to high, will be used to conduct rock acoustic emission experiments to find out the laws between rock acoustic emission activities and loading rates. The researches of this project can not only complete acoustic emission experimental study under diferent loading rates which could provide theoretical foundation for acoustic emission monitoring in the environment with frequent dynamic loads, but also provide researc

英文关键词： acoustic emission；rock dynamics；SHPB；dynamic fracturing mechanism；