CAJ | 학술논문

超声波波速作为一种无损检测手段，对岩石、岩体工程的损伤和破裂过程预测有一定的意义。从声波波速的角度出发，测试无受力和受力状态下干燥、饱水裂隙片岩的纵波波速，研究饱水天然裂隙片岩的波速特性及在压缩全过程中波速随应变的变化规律，探讨超声波特性与岩石损伤和失稳、破坏间的关系。研究结果表明：在未受力条件下，饱水试件比干燥试件的波速有明显的增加，平行裂隙波速V?饱水前后的增量在0.928%～15.357%范围内，垂直裂隙波速V⊥饱水前后的增量在20.042%～113.362%范围内，饱水前后波速的变化呈现出一定的分散性；垂直裂隙的波速V⊥比平行裂隙上的波速V?受水的影响明显，垂直裂隙方向上的岩石饱水波速较天然波速增加均在2倍以上，而平行裂隙上饱水岩石的波速变化小，岩石各向异性弱化。在压缩过程中，干燥和饱水裂隙片岩垂直裂隙方向波速V⊥在压密及线弹性阶段均表现出非线性的特性，在应力峰值点，岩石超声波波速急剧降低，岩石裂隙扩展明显。相比于垂直裂隙方向声波的变化，平行裂隙方向的波速V?只有在峰值应力处，波速有个跌落，但饱水状态下V?表现出一定波动性。
초성파파속작위일충무손검측수단，대암석、암체공정적손상화파렬과정예측유일정적의의。종성파파속적각도출발，측시무수력화수력상태하간조、포수렬극편암적종파파속，연구포수천연렬극편암적파속특성급재압축전과정중파속수응변적변화규률，탐토초성파특성여암석손상화실은、파배간적관계。연구결과표명：재미수력조건하，포수시건비간조시건적파속유명현적증가，평행렬극파속V?포수전후적증량재0.928%～15.357%범위내，수직렬극파속V⊥포수전후적증량재20.042%～113.362%범위내，포수전후파속적변화정현출일정적분산성；수직렬극적파속V⊥비평행렬극상적파속V?수수적영향명현，수직렬극방향상적암석포수파속교천연파속증가균재2배이상，이평행렬극상포수암석적파속변화소，암석각향이성약화。재압축과정중，간조화포수렬극편암수직렬극방향파속V⊥재압밀급선탄성계단균표현출비선성적특성，재응력봉치점，암석초성파파속급극강저，암석렬극확전명현。상비우수직렬극방향성파적변화，평행렬극방향적파속V?지유재봉치응력처，파속유개질락，단포수상태하V?표현출일정파동성。
In this study,the longitudinal wave velocities of schist specimens with saturated and dry fractures under loading and unloading conditions were measured,so that the variations and characteristics of wave velocity of saturated schist with fractures in the whole process of compression were obtained and relationship between wave velocity with the rock damage and failure were established. The wave velocities of the saturated specimen without loading were found to be significantly higher than those of dry specimen. The wave velocities V? parallel to cracks increased from 0.928%to 15.357%upon saturation,and the wave velocities V⊥ perpendicular to cracks increased from 20.042% to 113.362% upon saturation. The wave velocities V⊥ perpendicular to cracks were affected more evidently than those parallel to cracks. Under compression , the acoustic wave velocities perpendicular to cracks V⊥for both the schist specimens with the dry and saturated fractures were nonlinear in the elastic stage or the compression process and dropped drastically at the point of peak stress indicating the cracks were developed. While for dry specimens,the wave velocities V? parallel to cracks were reduced suddenly only at <br> the peak point. For the saturated specimens,the wave velocities V? parallel to cracks undulated.