IN-SITU STRESS MEASUREMENT BY OVERCORING AND HYDRAULIC FRACTURING OF PAHANG-SELANGOR RAW WATER TRANSFER PROJECT
DOI:
https://doi.org/10.11113/jt.v78.9636Keywords:
In-situ stress measurement, tunnel, overcoring, hydraulic fracturingAbstract
Estimation of in-situ stress orientation and magnitude is necessary for assessing the excavation risks for Pahang-Selangor Raw Water Transfer (PSRWT) tunnel project. However, the in-situ stress state of the rock generally differs according to area and depth. Therefore, the in-situ stress measurements test in the tunnel are determined in three (3) locations, which are at Adit 2, TBM 2, and Adit 3, in which the overburdens are 227, 1130, and 570 m, respectively. The stress relief method of overcoring technique and hydraulic fracturing by high stiffness system were applied for this project. The results demonstrate that the existence of high vertical stress was estimated in particular in the TBM 2. The maximum principal stress is determined nearly along the vertical direction. Meanwhile, the stress in the horizontal plane is relatively small, and the horizontal to vertical stress ratio is less than one (1). The direction of the horizontal stress obtained is N8E, N14W, and N41E. Results indicate that this method is suitable for estimating in-situ stresses in deep tunnels. The above data and their interpretations enhance the stress database for Peninsular MalaysiaReferences
Heidbach, O., Tingay, M., Barth, A., Reinecker, J., Kurfeß, D. and Müller, B., 2008. The World Stress Map database release 2008. www.world-stress-map.org/.
Kang, H., Zhang, X., Si, L., Wu, Y., & Gao, F. (2010). In-situ stress measurements and stress distribution characteristics in underground coal mines in China, 116, 333–345.
Martin, C. D., Kaiser, P. K., and Christiansson, R. 2003. Stress, instability and design of underground excavations. International Journal of Rock Mechanics & Mining Sciences, Vol.40, pp.1027–1047. Doi:10.1016/S1365-1609(03)00110-2.
Hudson, J. a., Cornet, F. H., and Christiansson, R. 2003. ISRM Suggested Methods for rock stress estimation-Part 1: Strategy for rock stress estimation. International Journal of Rock Mechanics and Mining Sciences. 40(7-8): 991–998.
Lehtonen, a., Cosgrove, J. W., Hudson, J. a., and Johansson, E. 2012. An examination of in-situ rock stress estimation using the Kaiser effect. Engineering Geology, 124, 24–37.
Thorsen, K. 2011. In-situ stress estimation using borehole failures — Even for inclined stress tensor. Journal of Petroleum Science and Engineering. 79(3-4): 86–100.
Sjöberg, J., Christiansson, R., and Hudson, J. a. 2003. ISRM Suggested Methods for rock stress estimation—Part 2: overcoring methods. International Journal of Rock Mechanics and Mining Sciences. 40 7-8: 999–1010.
Haimson, B. C., and Cornet, F. H. 2003. ISRM Suggested Methods for rock stress estimation-Part 3: hydraulic fracturing (HF) and/or hydraulic testing of pre-existing fractures (HTPF). International Journal of Rock Mechanics and Mining Sciences. 40(7-8): 1011–1020.
Obara, Y., and Sugawara, K. 2003. Updating the use of the CCBO cell in Japan : overcoring case studies. Rock Mechanics and Mining Sciences. 40: 1189–1203.
Stephansson, O., and Zang, A. 2012. ISRM Suggested Methods for Rock Stress Estimation-Part 5: Establishing a Model for the In-situ Stress at a Given Site. Rock Mechanics and Rock Engineering. 45(6): 955–969.
Ministry of Energy, Green Technology and Water, Malaysia (MEGTW) 2014. Completion Report for Lot 1-1 – Water Transfer Tunnel. Pahang-Selangor Raw Water Transfer Project. 12
Sheorey, P.R 1994. A Theory for In-situ Stresses in Isotropic and Transversely Isotropic Rock. International Journal of Rock Mechanics & Mining Sciences. 1: 23–34.
Hoek, E. and Brown, E.T. 1980. Underground Excavations in Rock. Institution of Mining and Metallurgy, London.
Hoek, E. 1999. Putting numbers to geology–an engineer’s viewpoint. Journal of Engineering Geology. 32(1): 1–19.
Brown, E. T., and Hoek, E. 1978. Technical Note Trends in Relationships between Measured In-Situ Stresses and Depth. International Journal of Rock Mechanics & Mining Sciences. 15: 211–215.
Downloads
Published
Issue
Section
License
Copyright of articles that appear in Jurnal Teknologi belongs exclusively to Penerbit Universiti Teknologi Malaysia (Penerbit UTM Press). This copyright covers the rights to reproduce the article, including reprints, electronic reproductions, or any other reproductions of similar nature.
