초음파 주사 검층 방법을 이용한 암반 강도 평가에 관한 연구 = A study on the estimation of in-situ rock strength using the data of the borehole acoustic scanner

다국어 초록 (Multilingual Abstract)

Borehole acoustic scanner is the useful method to collect the information of rock discontinuity(orientation, spacing, persistence, roughness, rock strength). The acoustic beams(1.4MHz) generated by a single transducer are sent toward the borehole wall and scan the wall in a tight helix as the tool moves along the borehole. We can find the physical properties of the rock by analysis of the reflected signals from the wall that include the information of amplitude and travel time. The value of amplitude relates to rock properties directly. The reason os why amplitude is changed by the reflection coefficient or impedance(density x seismic velocity) of a medium(water) and rock. Rock strength is calculated by using amplitude & travel time of borehole acoustic scanner. The result of rock strength in borehole acoustic scanner is following:
Ln(σ_c) = 0.000396996XA +2.54
0℃ is compressive strength(kg/㎠) and A is amplitude.

목차 (Table of Contents)

• 목차
• List of Illustrations = ii
• Abstract = iv
• 1. 서론 = 1
• 2. 이론 = 4
• 3. 실험 = 11
• 3.1 시료 및 시험편 제작 = 11
• 3.2 실험 과정 = 12
• 4. 실험 결과 및 고찰 = 14
• 4.1 압축강도 실험 = 14
• 4.2 초음파 주사 검층 실험 = 21
• 4.3 결과 및 고찰 = 30
• 5. 결론 = 35
• 참고문헌 = 36
• 부록 = 38
• 1. 전체 시료 = 39
• 2. Error 시험편 또는 Error 시료 = 40
• 3. 파괴된 시험편 = 42
• 감사의 글 = 46