Assessment of Strain Energy Storage and Rock Brittleness Indices of Rockburst Potential from Microfabric Characterizations
[1]
Zhao Zhiming, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, China.
[2]
Esamaldeen Ali, Department of Geology, Faculty of Petroleum and Minerals, Al Neelain University, Khartoum, Sudan.
[3]
Wu Guang, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, China.
[4]
Wang Xihua, School of Resources and Environment, Southwest Petroleum University, Chengdu, China.
Rockburst is one of the most crucial problems for the feasibility studies of underground excavation such as tunnel projects. However, direct standard methods for measuring rock burst potential indices such as Strain energy storage index (WET) and criterion of rock brittleness (B) are nearly difficult and need high sophisticated equipment. Therefore, in this study, an attempt was made to indirectly calculated as a function of microfabric characteristics such as quartz percentage and grain size by using simple regression statistical model. A dataset established by utilizing the relevant laboratory tests and petrographic image analysis on the rock samples assembled from pen Yin La and Ming Jiong tunnel along the La Ri railway, China. The results exhibit that the statistical WET and B models revealed responses with moderate to strong correlation coefficient, which proves higher potential of microfabrics analysis for predicting rock burst indices compared to traditional experimental measurements. Both rockburst indices increase with increasing percentage of quarts and grain size. It has been further been noted that in a certain tectonic setup, similar rock types with little different mineralogical composition and texture parameters might have different tendency to rock burst. This indicates that rock bursting potential is a petrographic characteristic dependent.
Rockburst, Rock Brittleness, Microfabric, Strain Energy Storage Index, Tunnel
[1]
Cook NGW. The basic mechanics of rockbursts, J. South African Inst. Mining and Metallurgy, 66 (1966) 56-70.
[2]
Wang JA, Park HD. Comprehensive prediction of rockburst based on analysis of strain energy in rocks: Tunn. Undergr. Space Technol. 16 (2001) 49–57.
[3]
Pan JN, Meng ZP. Genesis of rock bursts in collieries and its controlling factors under deep mining condition. In: Wang, Yajun, Huang, Ping, Li, Shengcai (Eds.), Proceedings of the 2004 International Symposium on Safety Science and Technology. Science Press, Beijing/New York, (2004) 302–308.
[4]
Tang LZ, Wang WX. New rock burst proneness index: Chin. J. Rock Mech. Eng. 21 (2002) 874–878 (in Chinese).
[5]
Li ZH, Dou LM, LuCP.et al., Study on fault induced rock bursts: J China Univ Min Technol. 18 (2008) 0321–0326
[6]
He M, Miao J, LiD, WangC. Experimental study on rockburst processes of granite specimen at great depth: Chinese Journal of Rock Mechanics and Engineering. 26 (2007) 865–876 (in Chinese).
[7]
Kwasniewski M, SzutkowskiI, Wang JA. Study of ability of coal from seam 510 for storing elastic energy in the aspect of assessment of hazard in Porabka-Klimontow Colliery: Sci. Rept. Silesian Technical University.1994.
[8]
Qiao CS, Tian ZY. Study of the possibility of rockburst in Dong-gua-shan Copper Mine: Chinese J. Rock Mech. Eng. Žexp. 17 (1998) 917-921.
[9]
Wang YH, LiWD, LiQG. Fuzzy estimation method of rockburst prediction: Chinese J. Rock Mech. Eng.17 (1998) 493-501. (in Chinese)
[10]
Helibronner R. Automatic grain boundary detection and grain size analysis using polarization micrographs or orientation images, Journal of Structural Geology, 22 (2000)969– 981.
[11]
Prikryl R. Some microstructural aspects of strength variation in rocks, Int. J. Rock Mech, Min. Sci. 38 (2001) 671-682.
[12]
Prikryl R. Assessment of rock geomechanical quality by quantitative rock fabric coefficients: limitations and possible source of misinterpretations, Engineering Geology, 87 (2006) 149–162.
[13]
Åkesson U, Lindqvist JE, Göransson, M., Stigh,J. Relationship between texture and mechanical properties of granites, central Sweden, by use of image-analyzing technique, Bulletin of Engineering Geology and the Environment, 60 (2001) 277–284.
[14]
Akensson U, Stingh J, Lindqvist JE, Goransson, M. The influence of foliation on fragility of granitic rocks, image analysis and quantitative microscopy, Engineering Geology, 68 (2003) 275–288.
[15]
Raisanen M. Relationship between texture and mechanical properties of hybrid rocks from the Jaala-litti complex, Southeastern Finland, Engineering Geology, 74 (2004)197–211.
[16]
French WJ, Kermani S, Mole CF. Petrographic evaluation of aggregate parameters, Proceedings of the 8th Euroseminar on Microscopy Applied to Building Materials. Athe`nesdepartement de geologie, Athens, (2001) 557–564.
[17]
MengZ,PanJ,Correlation between petrographic failure duration in clastic rocks, Engineering Geology, 89 (2007) 258–265.
[18]
Rigopoulos I, Tsikouras B, Pomonis P, Hatzipanagiotou K. The influence of alteration on the engineering properties of dolerites: the examples from the Pindos and Vourinos ophiolites (northern Greece), International Journal of Rock Mechanics and Mining Science, 47 (2010) 69–80.
[19]
Gupta V, Sharma R. Relationship between textural, petrophysical and mechanical properties of quartzites, a case study from northwestern Himalaya: Engineering Geology, 135 (2012)1–9.
[20]
Yesiloglu-Gultekin N, Sezer EA, Gokceoglu C, Bahyan H. An application of adaptive neuro fuzzy inference system for estimating the uniaxial compressive strength of certain granitic rocks from their mineral contents, Expert Systems with Applications, Vol. 40 (2013) 921–928.
[21]
Seo YS, Jeong GC, Kim JS, Ichikawa Y. Microscopic observation and contact stress analysis of granite under compression, Engineering Geology, 63 (2002) 259–275.
[22]
Heap MJ, Faulkner DR, Meredith PG. Vinciguerra, S. Elastic moduli evolution and accompanying stress changes with increasing crack damage: implications for stress changes around fault zones and volcanoes during deformation, Geophysical Journal International, 183 (2010) 225–236.
[23]
ASTM, Standard practice for preparing rock core specimens and determining dimension and shape tolerances, American Society for Testing and Materials, D4543.(1995)
[24]
ASTM, Standard test method for unconfined compressive strength of intact rock core specimens, American Society for Testing and Materials, D2938.(1995)
[25]
ASTM, Standard test method for splitting tensile strength of intact rock core specimens, American Society for Testing and Materials, D3967.(1995)
[26]
Åkesson U. Microstructures in granites and marbles in relation to their durability as construction materials: Ph.D. dissertation, The University of Gothenburg, Sweden, 2004
[27]
Lindqvist JE, Åkesson U, Malaga K. Microstructure and functional properties of rock materials, Materials Characterization, 58 (2007) 1183–1188.
