摘要
针对目前裂隙岩体损伤破裂演化监测及量化预测研究的不足,开展了交叉裂隙岩体损伤破裂演化全程超声波监测试验,研究了裂隙岩体损伤破裂演化过程的超声波特性并进行了量化预测探讨。结果表明,波速可以较好地反映裂隙岩体的损伤破裂演化进程,首波波幅则可以综合反映裂隙岩体的变形损伤破裂演化全过程,将波速、首波波幅二者结合分析可以实现更准确的量化预测;加载初期衰减系数有正有负,加载中后期衰减系数明显增大,尤其在加载后期增大更为明显,其反映了裂隙岩体内部变形、损伤和破裂演化进程,可以通过对衰减系数的分析实现对裂隙岩体演化进程的量化预测;随着加载载荷的增加其波形由密变疏,波幅减小,波峰、波谷数量减少,在加载后期波形稀疏尤为明显,通过对监测波形的对比分析可以预测裂隙岩体演化进程;取加载初期波形中的任意波峰位置的时间点来截断监测期间的所有波形,分析该时间点所对应波幅的变化,同样可以达到通过首波波幅量化预测裂隙岩体演化进程的效果,并非一定是首波波幅;R_s,m_b,s,σ_1均可以作为量化指标用于裂隙岩体损伤破裂演化的预测,这些量化指标均对裂隙岩体的损伤破裂演化进程有很好的敏感性。
With the current lack of monitoring and quantitative forecast of damage fracture evolution of fractured rock mass, ultrasonic monitoring tests of the entire-process evolution of rock mass with cross-cracks were carried out, the ultrasonic characteristics of damage fracture evolution of fractured rock mass were researched, and quantitative prediction was discussed. The results have shown that the wave velocity can well reflect the damage fracture evolution of fractured rock mass, the first wave am- plitude can comprehensively reflect the whole evolution process of damage and fracture of fractured rock mass, so the analysis of the combination of wave velocity and the first wave amplitude can achieve a more accurate quantitative prediction; at the beginning stage of loading, the attenuation coefficients are both positive and negative, and at the mid-to-late stage, attenuation coefficients increase signifi- cantly, specially at the late stage, which reflects the evolution process of deformation, damage, andrupture of fractured rock mass： quantitative forecast of the evolution process of fractured rock mass can be achieved through the analysis of attenuation coefficients; the amplitude decreases and the number of the peaks and troughs reduce with the increase of the load, and at the later stage loading, waveform scarcity is particularly evident： the evolution process of fractured rock mass can be predicted through comparing the monitored waveform; the effect of quantitative prediction of the evolution process of fractured rock mass through first wave amplitude can also be achieved by taking the peak position at any time of the waveform at the beginning stage of loading to cut off all waveforms at the same time point during monitoring, and analyzing the changes of amplitude of the corresponding time point, so the first wave amplitude is not a must; Rs,mb,s,σ1can be used as quantitative indexes to predict the damage and rupture evolution of fractured rock mass, these quantitative indicators have good sensitivity to the progress of the damage and rupture evolution of fractured rock mass.
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2017年第2期378-383,共6页
Journal of Mining & Safety Engineering
基金
山东省自然科学基金项目(ZR2015EL016)
山东理工大学青年教师发展支持计划项目
山东理工大学一级学科重点支持计划项目
关键词
裂隙岩体
单轴压缩试验
超声波监测
破裂演化
量化预测
衰减系数
fractured rock mass
uniaxial compression test
ultrasonic monitoring
rupture evolution
quantized prediction
attenuation coefficient
