基于声发射技术的白云岩多级循环荷载损伤特性研究  

Study on the Damage Characteristics of Dolomite with Multi-Stage Cyclic Loading Based on Acoustic Emission Technique

作　　者：潘孝新 李勇 易武[1,2] 黄晓虎 何涛 PAN Xiaoxin;LI Yong;YI Wu;HUANG Xiaohu;HE Tao(National Field Observation and Research Station of Landslides in Three Gorges Reservoir Area of Yangtze River,China Three Gorges University,Yichang 443002,China;Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education(China Three Gorges University),Yichang 443002,China;Hydrogeology and Engineering Geology Institute of Hubei Geological Bureau,Jingzhou 434020,China)

机构地区：[1]三峡大学湖北长江三峡滑坡国家野外科学观测研究站,湖北宜昌443002 [2]三峡库区地质灾害教育部重点实验室(三峡大学),湖北宜昌443002 [3]湖北省地质局水文地质工程地质大队,湖北荆州434020

出　　处：《三峡大学学报(自然科学版)》2025年第2期33-40,共8页Journal of China Three Gorges University:Natural Sciences

基　　金：国家自然科学基金项目(U21A2031,42007237,42107489);三峡库区地质灾害教育部重点实验室开放基金项目(2020KDZ09)。

摘　　要：为研究多级循环荷载下岩石损伤演化规律及声学前兆响应特征,对白云岩试样开展不同加载波形的多级循环荷载单轴试验,以相同条件下的常规单轴试验作为对照组,对比分析多级循环荷载作用下白云岩试样的变形特征和强度变化机制,同时结合声发射技术分析多级循环荷载过程中白云岩的损伤破坏特征.结果表明:在达到峰值强度之前,多级循环荷载并未改变白云岩应力-应变曲线的基本形态,多级循环荷载作用下的应力-应变曲线的上升趋势与常规单轴加载时保持一致;与常规单轴试验相比,多级循环荷载会加重白云岩的损伤,增加其岩石内部微破裂事件的发生频率导致内部积聚的能量进一步增大,这种累积效应最终导致白云岩在破坏时释放出更大的能量;通过对比分析两种循环荷载试验下的Felicity比的下降速率以及岩样破坏时的Felicity值,结果表明正弦波多级循环荷载比三角波多级循环荷载对岩石的损伤破坏更为严重;在常规单轴试验中声发射振铃计数和能量表现出“频发期”可作为岩石即将失稳破坏的前兆预测信号.在正弦波多级循环荷载中声发射出现振铃计数和能量持续突增时可作为岩石破裂的前兆信息,可为工程岩体灾害的监测与预警提供参考.In order to study the evolution of rock damage and acoustic precursor response characteristics under multistage cyclic loading,multistage cyclic loading uniaxial tests with different loading waveforms were carried out on dolomite specimens,and conventional uniaxial tests under the same conditions were tested as a control group.The deformation characteristics and the mechanism of strength change of dolomite specimens under multistage cyclic loading were compared and analyzed,and the damage and destruction characteristics of dolomite in the process of multistage cyclic loading were also analyzed according to the acoustic emission technology.The results show that:the multi-stage cyclic loading did not change the basic shape of the stress-strain curve of dolomite before reaching the peak strength,and the increasing trend of the stress-strain curve under multi-stage cyclic loading is consistent with that of conventional uniaxial loading.Compared with the conventional uniaxial test,the multistage cyclic loading aggravates the damage of dolomite,increases the frequency of microfracture events within the rock and leads to a further increase in the energy accumulated within the rock,thus ultimately results in the release of more energy and a more severe fracture of the dolomite when it is damaged.By comparing and analyzing the decrease rate of Felicity ratio under two cyelic loading tests and the Felicity value when the rock sample is destroyed,the results show that the sine wave multi-stage cyclic loading is more serious than the triangular wave mult-stage cyclic loading.In uniaxial compression test,the acoustic emission ring counts and energies show a“frequent period”,which can be used as a precursor predictive signal for the impending destabilization of the rock.In the sine wave cyclic loading and unloading,the acoustic emission ringing counts and energy increase can be used as the precursor information of rock rupture,which can be used as a reference for the monitoring and early warning of the engineering rock dis

关 键 词：白云岩 多级循环荷载 损伤特性 声发射 Felicity比 

分 类 号：TU45[建筑科学—岩土工程]