Abstract
In this paper, mesoscopic structural changes and the associated strain localization behaviors were investigated quantitatively using X-ray computerized tomography (CT) and ultrasonic measurement techniques. While the effects of rock blocks on the macroscopic mechanical of block-in-matrix soil (bimsoil) have been widely studied, the physical mesoscale mechanisms governing the bimsoil deformation are still poorly understood. Triaxial compression experiment was conducted on bimsoil sample with rock proportion of 30% (mass ratio). The mesostructural changes were quantitatively studied using macroscopic stress-strain description and mesoscopic CT image identification. Under triaxial compression, the stress-strain curve of bimsoil presents strain hardening behavior, and the interactions between rock block and soil matrix result in the strain localization and mesostructural changes. In addition, the damage evolution behaviors of bimsoil are different from soil and rock, and spatial kinematic of rock blocks results in not only the fluctuation of CT value, ultrasonic pulse velocity (UPV), and transmitted ratio (TR) but also the crack geometry characteristics (e.g., length, area, width, and fractal dimension). What is more, contaction and separation between soil matrix and rock block occur repeatedly during sample deformation, and the fractal dimension of the crack distribution becomes larger. Through a series of mesostructural change analysis, the mesomechanisms of bimsoil under triaxial deformation have been first discussed.
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References
Afifipour M, Moarefvand P (2014) Failure patterns of geomaterials with block-in-matrix texture: experimental and numerical evaluation. Arab J Geosci 7:2781–2792
Coli N, Berry P, Boldini D (2011) In situ non-conventional shear tests for the mechanical characterisation of a bimrock. Int J Rock Mech Min Sci 48(1):95–102
Donaghe RT, Torrey VH (1994) Proposed new standard test method for laboratory compaction testing of soil-rock mixtures using standard effort. Geotech Test J 17(3):387–392
Fang XW, Chen ZH, Shen CN, Zhang W (2002) Meso testing research on structure damage evolution of natural Q2 loess. J Hydraul Eng 39(8):940–946
Ge XR, Ren JX, Pu YB, Ma W, Yuan LZ (1999) A real-time CT triaxial testing study of meso-damage evolution law of coal. Chin J Rock Mech Eng 18(5):497–502
Ge XR, Ren JX, Ping XB, Ma W, Zhu YL (2000) Mesoscopic damage propagation of rock using real-time CT test. Sci China (Ser E) 30(2):104–111
Higo Y, Oka F, Kimoto S, Matsushima Y (2011) Study of strain localization and microstructural changes in partially saturated sand during triaxial tests using microfocus X-ray CT. Soils Found 51(1):95–111
Higo Y, Oka F, Sato T (2013) Investigation of localized deformation in partially saturated sand under triaxial compression using microfocus X-ray CT with digital image correlation. Soils Found 53(2):181–198
Huang ZH, Zhu LJ, Pu YB, Zhou XH (2004) CT analysis of dynamic change of mechanical properties of red clay under triaxial stress. Rock Soil Mech 25(8):1215–1219
Jiang XG, Cui P, Ge YG (2015) Effects of fines on the strength characteristics of mixtures. Eng Geol 198:78–86
Kim FH, Penumadu D, Gregor J, Kardjilov N, Manke I (2012) High-resolution neutron and X-ray imaging of granular materials. J Geotech Geoenviron 139(5):715–723
Kodaka T, Higo Y, Takyu T (2001) Deformation and failure characteristics of rectangular clay specimens under three-dimensional condition. In: Proceedings of the 15th international conference on soil mechanics and geotechnical engineering, August 27–31, Istanbul, Turkey, 1, pp 167–170
Lindquist ES (1994) The strength and deformation properties of melange. Ph.D. thesis, Department of Civil Engineering, University of California, Berkeley
Medley EW (2001) Orderly characterization of chaotic Franciscan melanges. Eng Geol 4:20–33
Medley E, Lindquist ES (1995) The engineering significance of the scale-independence of some Franciscan Melanges in California, USA. In: Daemen JK, Schultz RA (eds) Proceedings of the 35th US rock mechanics symposium. Balkema, Rotterdam, pp 907–914
Michalowski RL, Shi L (2003) Deformation patterns of reinforced foundation sand at failure. J Geotech Geoenviron 29(6):439–449
Muir Wood D (2002) Some observations of volumetric instabilities in soils. Int J Solids Struct 39:3429–3449
MWRPRC (Ministry of Water Resources of the People’s Republic of China) (1999) GB/T 50123–1999: Standard for soil test method. MWRPRC, Beijing
Otani J, Mukunoki T, Obara Y (2000) Characterization of failure in sand under triaxial compression using an industrial X-ray CT scanner. Soils Found 40(2):111–118
Rahardjo H, Indrawan I, Leong EC, Yong W (2008) Effects of coarse-grained material on hydraulic properties and shear strength of top soil. Eng Geol 101:165–173
Roscoe KH (1970) The influence of strains in soil mechanics. Ge’otechnique 20(2):129–170
Vardoulakis I, Graf B (1982) Imperfection sensitivity of the biaxial test on dry sand. In: Vermeer PA, Luger HJ (eds) Proceedings of the IUTAM conference on deformation and failure of granular materials, Delft. Balkema, Rotterdam, pp 485–492
Vardoulakis I, Sulem J (1995) Bifurcation analysis in geomechanics. Blackie Academic & Professional, Glasgow
Wang Y, Li X, Zhang B, Wu YF (2014) Meso-damage cracking characteristics analysis for rock and soil aggregate with CT test. Sci China Technol Sci 57:1361–1371
Wang Y, Li X, Wu YF, Lin C (2015a) Experimental study on meso-damage cracking characteristics of RSA by CT test. Environ Earth Sci 73(9):5545–5558
Wang Y, Li X, Wu YF (2015b) Damage evolution analysis of SRM under compression using X-ray tomography and numerical simulation. Eur J Environ Civ Eng 19:400–417
Wang Y, Li X, Zheng B, Zhang B, Wang JB (2015c) Real-time ultrasonic experiments and mechanical properties of soil and rock mixture during triaxial deformation. Géotechnique Lett 5:281–286
Wang Y, Li X, Hu RL (2015d) Experimental study of the ultrasonic and mechanical properties of SRM under compressive loading. Environ Earth Sci 74(1):5023–5037
Wang Y, Li X, Zheng B, He JM, Li S (2016a) Macro–meso failure mechanism of soil–rock mixture at medium strain rates. Géotechnique Lett (6). https://doi.org/10.1680/jgele.15.00118
Wang Y, Li X, Zheng B, Mao TQ, Hu RL (2016b) Investigation of the effect of soil matrix on flow characteristics for soil and rock mixture. Géotechnique Lett 6(3):226–233
Xu WJ, Wang SJ, Zhang HY, Zhang ZL (2016) Discrete element modelling of a soil-rock mixture used in an embankment dam. Int J Rock Mech Min Sci 86:141–156
Yang GS, Xie DY, Zhang CQ (1998) Quantitative analysis of CT distribution law of rock damage. Chin J Rock Mech Eng 17(3):279–285
Acknowledgements
The authors would like to thank the editors and the anonymous reviewers for their helpful and constructive comments.
Funding
This work was supported by the Fundamental Research Funds for the Central Universities (2302017FRF-TP-17-027A1), the National Key Technologies Research and Development Program (2017YFC0804103, 2017YFC0804609), the National Natural Science Foundation of China (Grant Nos. 41502294, 51574014), and the National Key Basic Research Program of China (973 Program) (No. 2015CB060200).
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Wang, Y., Li, C.H. Investigation of mesostructural changes in bimsoil during triaxial deformation: an insight using X-ray computed tomography and ultrasonic measurement. Arab J Geosci 11, 629 (2018). https://doi.org/10.1007/s12517-018-3989-1
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DOI: https://doi.org/10.1007/s12517-018-3989-1