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http://dx.doi.org/10.12989/gae.2015.8.2.237

Analytical solutions for crack initiation on floor-strata interface during mining  

Zhao, Chongbin (Computational Geosciences Research Centre, Central South University)
Publication Information
Geomechanics and Engineering / v.8, no.2, 2015 , pp. 237-255 More about this Journal
Abstract
From the related engineering principles, analytical solutions for horizontal crack initiation and propagation on a coal panel floor-underlying strata interface due to coal panel excavation are derived in this paper. Two important concepts, namely the critical panel width of horizontal crack initiation on the panel floor-underlying strata interface and the critical panel width of vertical fracture (crack) initiation in the panel floor, have been presented. The resulting analytical solution indicates that: (1) the first criterion can be used to express the condition under which horizontal plane cracks (on the panel floor-underlying strata interface or in the panel floor because of delamination) due to the mining induced vertical stress will initiate and propagate; (2) the second criterion can be used to express the condition under which vertical plane cracks (in the panel floor) due to the mining induced horizontal stress will initiate and propagate; (3) this orthogonal set of horizontal and vertical plane cracks, once formed, will provide the necessary weak network for the flow of gas to inrush into the panel. Two characteristic equations are given to quantitatively estimate both the critical panel width of vertical fracture initiation in the panel floor and the critical panel width of horizontal crack initiation on the interface between the panel floor and its underlying strata. The significance of this study is to provide not only some theoretical bases for understanding the fundamental mechanism of a longwall floor gas inrush problem but also a benchmark solution for verifying any numerical methods that are used to deal with this kind of gas inrush problem.
Keywords
crack initiation; analytical solution; panel floor fracture; critical panel width;
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1 Ali, A.Y. and Bradshaw, S.M. (2010), "Bonded-particle modelling of microwave-induced damage in ore particles", Min. Eng., 23(10), 780-790.   DOI
2 Bunger, A.P., Menand, T., Cruden, A., Zhang, X. and Halls, H. (2013), "Analytical predictions for a natural spacing within dyke swarms", Earth Planet. Sci. Lett., 375, 270-279.   DOI
3 Exadaktylos, G. (2012), "A study of the transient fluid flow around a semi-infinite crack", Int. J. Solid. Struct., 49(23-24), 3323-3334.   DOI
4 Faccanoni, G. and Mangeney, A. (2013), "Exact solution for granular flows", Int. J. Numer. Anal. Method. Geomech., 37(10), 1408-1433.   DOI
5 Hudson, J.A., Brown, E.T., Fairhurst, C. and Hoek, E. (1993), Comprehensive Rock Engineering: Principles, Practice and Projects, Volume 1-5, Pergamon Press, New York, NY, USA.
6 Karim, M.R., Krabbenhoft, K. and Lyamin, A.V. (2013), "Permeability determination of porous media using large-scale finite elements and iterative solver", Int. J. Numer. Anal. Method. Geomech., 38(10), 991-1012.   DOI
7 Noack, K. (1995), "Control of high gas emissions in underground coal mines", Int. J. Coal Geol., 35(1-4), 57-82.   DOI
8 Stark, R.F. and Booker, J.R. (1997), "Surface displacements of a non-homogeneous elastic half-space subjected to uniform surface tractions. Part I: Loading on arbitrarily shaped areas", Int. J. Numer. Anal. Method. Geomech., 21(6), 361-378.   DOI
9 Wang, J.G., Kabir A., Liu, J.S. and Chen, Z.W. (2012), "Effects of non-Darcy flow on the performance of coal seam gas wells", Int. J. Coal Geol., 93, 62-74.   DOI
10 Wang, J.G., Liu, J.S. and Kabir, A. (2013), "Combined effects of directional compaction, non-Darcy flow and anisotropic swelling on coal seam gas extraction", Int. J. Coal Geol., 109-110, 1-14.   DOI
11 Xia, M. and Zhou, K.P. (2010), "Particle simulation of failure process of brittle rock under triaxial compression", Int. J. Min. Metal. Mater., 17(5), 507-513.   DOI
12 Ye, Z., Chen, D. and Wang, J.G. (2014), "Evaluation of non-Darcy effect in coalbed methane production", Fuel, 121, 1-10.   DOI
13 Zhao, C. and Valliappan, S. (1995), "Finite element modelling of methane gas migration in coal seams", Comput. Struct., 55(4), 625-629.   DOI
14 Zhao, C., Hebblewhite, B.K. and Galvin, J.M. (2000), "Analytical solutions for mining induced horizontal stress in floors of coal mining panels", Comput. Method. Appl. Mech. Eng., 184(1), 125-142.   DOI
15 Zhao, C., Hobbs, B.E. and Ord, A. (2008), Convective and Advective Heat Transfer in Geological Systems, Springer, Berlin, Germany.
16 Zhang, X., Jeffrey, R.G., Bunger, A.P. and Thiercelin, M. (2011), "Initiation and growth of a hydraulic fracture from a circular wellbore", Int. J. Rock Mech. Min. Sci., 48(6), 984-995.   DOI