| Title |
Quantitative Damage Assessment in KURT Granite by Acoustic Emission |
| Authors |
이경수(Lee, Kyung-Soo) ; 김진섭(Kim, Jin-Seop) ; 최희주(Choi, Hey-Joo) ; 이창수(Lee, Chang-Soo) |
| DOI |
https://doi.org/10.12652/Ksce.2012.32.6C.305 |
| Keywords |
미소파괴음;균열손상응력;원자력연구소 지하처분연구시설;손상도;모어-쿨롱의 파괴규준 acoustic emission;crack damage stress;KAERI underground research tunnel;damage degree;mohr-coulomb failure criterion |
| Abstract |
This paper presents the quantitative damage assessment of granite taken from KAERI Underground Research Tunnel using acoustic emission (AE). The results determined showed the crack initiation and crack damage stress occurred at 48%, 72% of uniaxial compressive strength (UCS) and until the applied stress level was reached the crack damage stress, the damage degree was 0.06. When the applied stress exceeded 80%, 90% of UCS, the damage degree were 0.34, 0.06 and which were similar to those obtained from axial deformation modulus. The simply regression analysis was used to interpret the relationship of the two damage assessment techniques and the two were highly correlated ($R^2$=0.90). Therefore, damage degree based on the AE energy and mohr-coulomb failure criterion were adopted to predict the mechanical properties. As results, the axial deformation modulus, rock strength, internal friction angle, and cohesion of KURT rock were reduced 6%, 12%, 7%, and 3% until the applied stress was 70% of UCS. But when the applied stress reached 90% of UCS, the results were more reduced 69%, 72%, 62%, and 24%, respectively. |