摘要
地下工程围岩体处于三维地应力环境中,地应力通过改变岩体孔隙压密、裂隙萌生与扩展程度等,影响岩石的物理力学特性,进而导致不同超声波参数发生不同程度的改变。为了研究不同岩石超声波参数对三维地应力的敏感性及其传播衰减特性,利用三维静应力岩石超声波测试试验系统,对红砂岩进行不同三维地应力工况下的超声波传播试验。选取超声波首波波形进行分析,研究岩石超声波速、首波幅值和首波能量随三维静应力的变化关系,构建岩石声学参数的演化经验模型;分析不同岩石超声波参数对三维地应力的敏感性,探索超声波衰减机制。结果表明:(1)相同围压工况下,随着轴向静应力的增加,岩石超声波纵波波速先快速增加后缓慢变化,整体呈指数函数形式变化;红砂岩首波幅值先增大后减小,二者呈现高斯函数关系;首波能量整体上呈现先增加后减小的趋势。(2)相同轴向静应力工况下,岩石超声波速、首波幅值及首波能量随围压增大均呈上升趋势,围压有助于岩石超声波的传播。(3)不同声学参数对岩石内部损伤演化的敏感程度不同,相对于超声波速,首波幅值和首波能量对初始孔隙压密和损伤演化均具有较强的敏感性,更适合表征围岩体的损伤演化性能。
Rock masses in underground engineering are subjected to three-dimensional in-situ stress,which influences their physical and mechanical properties by controlling pore compaction,crack initiation,and propagation.These processes result in varying degrees of change in different ultrasonic parameters.To investigate the sensitivity of various ultrasonic parameters to three-dimensional in-situ stress and their attenuation characteristics,ultrasonic wave propagation tests were conducted on red sandstone using a three-dimensional static stress ultrasonic testing system.By analyzing the selected head waveforms,the variations of ultrasonic wave velocity,head wave amplitude and head wave energy with the three-dimensional static stress were investigated.Empirical models of rock ultrasonic parameters were developed.The sensitivity of each parameter to the three-dimensional in-situ stress was assessed,and the attenuation mechanism was explored.The results indicate that under constant confining pressure,ultrasonic wave velocity increases rapidly with increasing axial static stress and then stabilizes,following an exponential relationship.The head wave amplitude of red sandstone initially increases and then decreases,exhibiting a Gaussian distribution.Similarly,head wave energy shows an overall trend of first increasing and then decreasing.Under constant axial static stress,ultrasonic wave velocity,head wave amplitude,and head wave energy all increase with rising confining pressure,indicating that confining pressure enhances ultrasonic wave propagation.Different acoustic parameters exhibit varying sensitivities to rock damage evolution.Compared to ultrasonic velocity,head wave amplitude and head wave energy are more sensitive to both initial pore compaction and damage evolution,making them more suitable for characterizing the damage evolution of engineering rock masses.
作者
金解放
熊慧颖
肖莜丰
彭孝旺
JIN Jie-fang;XIONG Hui-ying;XIAO You-feng;PENG Xiao-wang(School of Civil and Surveying Engineering,Jiangxi University of Science and Technology,Ganzhou,Jiangxi 341000,China)
出处
《岩土力学》
北大核心
2025年第S1期183-194,共12页
Rock and Soil Mechanics
基金
国家自然科学基金(No.52174112)
江西省自然科学基金(No.20232ACB204015)
江西省研究生创新专项资金(No.YC2023-B218)
关键词
三维地应力
岩石超声波
传播衰减
首波分析
参数敏感性
three-dimensional in-situ stress
rock ultrasonic wave
propagation attenuation
head wave analysis
parameters sensitivity
