A miniature triaxial apparatus for investigating the micromechanics of granular soils with <i>in situ</i> X-ray micro-tomography scanning

doi:10.1007/s11709-019-0599-2

Front. Struct. Civ. Eng.

2020, Vol. 14

Issue (2) : 357-373 https://doi.org/10.1007/s11709-019-0599-2

RESEARCH ARTICLE

A miniature triaxial apparatus for investigating the micromechanics of granular soils with in situ X-ray micro-tomography scanning

Zhuang CHENG¹, Jianfeng WANG²(

), Matthew Richard COOP³, Guanlin YE⁴

¹. Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong 999077, China
². Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China
³. Department of Civil, Environmental and Geomatic Engineering, University College London, London WC1E 6BT, UK
⁴. Department of Civil Engineering, Shanghai Jiaotong University, Shanghai 200240, China

Download: PDF(5562 KB) HTML
Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks

Abstract

The development of a miniature triaxial apparatus is presented. In conjunction with an X-ray micro-tomography (termed as X-ray μCT hereafter) facility and advanced image processing techniques, this apparatus can be used for in situ investigation of the micro-scale mechanical behavior of granular soils under shear. The apparatus allows for triaxial testing of a miniature dry sample with a size of $8 mm × 16 mm$ (diameter $×$ height). In situ triaxial testing of a 0.4–0.8 mm Leighton Buzzard sand (LBS) under a constant confining pressure of 500 kPa is presented. The evolutions of local porosities (i.e., the porosities of regions associated with individual particles), particle kinematics (i.e., particle translation and particle rotation) of the sample during the shear are quantitatively studied using image processing and analysis techniques. Meanwhile, a novel method is presented to quantify the volumetric strain distribution of the sample based on the results of local porosities and particle tracking. It is found that the sample, with nearly homogenous initial local porosities, starts to exhibit obvious inhomogeneity of local porosities and localization of particle kinematics and volumetric strain around the peak of deviatoric stress. In the post-peak shear stage, large local porosities and volumetric dilation mainly occur in a localized band. The developed triaxial apparatus, in its combined use of X-ray μCT imaging techniques, is a powerful tool to investigate the micro-scale mechanical behavior of granular soils.

Keywords triaxial apparatus X-ray μCT in situ test micro-scale mechanical behavior granular soils

Corresponding Author(s): Jianfeng WANG

Just Accepted Date: 08 January 2020 Online First Date: 11 March 2020 Issue Date: 08 May 2020

Cite this article:

Zhuang CHENG,Jianfeng WANG,Matthew Richard COOP, et al. A miniature triaxial apparatus for investigating the micromechanics of granular soils with in situ X-ray micro-tomography scanning[J]. Front. Struct. Civ. Eng., 2020, 14(2): 357-373.

URL:

https://academic.hep.com.cn/fsce/EN/10.1007/s11709-019-0599-2
https://academic.hep.com.cn/fsce/EN/Y2020/V14/I2/357

Fig.1 Schematic of a typical parallel beam X-ray

μ

CT facility.

Fig.2 The triaxial system: (a) schematic of the triaxial system; (b) photograph of the triaxial apparatus.

Fig.3 A closer view of the axial loading device.

Fig.4 A schematic of the seal design of the apparatus.

Fig.5 Data acquisition and controlling system.

Fig.6 Photograph of the sample maker.

Fig.7 The process of making a sample. (a) A porous stone and a membrane; (b) sample maker; (c) fixing of the membrane; (d) filling of sand grains; (e) installation of a cushion plate; (f) removal of the sample maker.

Fig.8 The triaxial apparatus being used in conjunction with the synchrotron radiation facility: (a) a photograph; (b) a schematic of the connection between the apparatus and the synchrotron radiation facility.

Fig.9 Stress-strain curves of the LBS sample: (a) deviatoric stress vs. axial strain, (b) volumetric strain vs. axial strain.

Fig.10 Vertical slices of the sample at different scans. (a) 0%; (b) 0.98%; (c) 4.94%; (d) 10.40%; (e) 15.34%.

Fig.11 Illustration of the image processing of a 2D horizontal slice to determine sample porosity: (a) raw CT image; (b) filtered CT image; (c) binary image; (d) after 12 times of dilation of image (c); (e) after filling holes of image (d); (f) after 12 times of erosion of image (e).

Fig.12 Intensity histograms of the CT image before and after image filtering.

Fig.13 Illustration of the image processing of a 2D horizontal slice to determine local porosities: (a) a binary image of separated particles; (b) a binary image of an extracted particle; (c) distance transformation of image (a); (d) distance transformation of image (b); (e) extracted local void region; (f) the local void region superimposed on image (a).

Fig.14 Comparison between the volumetric strains of the sample as calculated by two methods.

Fig.15 A vertical slice of local porosity distributions of the sample at different axial strains.

Fig.16 Normalized frequency distributions of local porosity of the sample at different axial strains.

Fig.17 Particle displacement and rotation of the sample during the axial strain increments of: (a) 0~0.98%; (b) 0.98~4.94%; (c) 4.94~10.40%; (d) 10.40~15.34%.

Fig.18 Volumetric strain distributions of the sample during the axial strain increments of: (a) 0~0.98%; (b) 0.98~4.94%; (c) 4.94~10.40%; (d) 10.40~15.34%.

1	K L Lee, I Farhoomand. Compressibility and crushing of granular soil in anisotropic triaxial compression. Canadian Geotechnical Journal, 1967, 4(1): 68–86 https://doi.org/10.1139/t67-012
2	R J Fragaszy, M E Voss. Undrained compression behavior of sand. Journal of Geotechnical Engineering, 1986, 112(3): 334–347 https://doi.org/10.1061/(ASCE)0733-9410(1986)112:3(334)
3	M I Arshad, F S Tehrani, M Prezzi, R Salgado. Experimental study of cone penetration in silica sand using digital image correlation. Geotechnique, 2014, 64(7): 551–569 https://doi.org/10.1680/geot.13.P.179
4	J Wang, H Yan. DEM analysis of energy dissipation in crushable soils. Soil and Foundation, 2012, 52(4): 644–657 https://doi.org/10.1016/j.sandf.2012.07.006
5	J Wang, H Yan. On the role of particle breakage in the shear failure behavior of granular soils by DEM. International Journal for Numerical and Analytical Methods in Geomechanics, 2013, 37(8): 832–854 https://doi.org/10.1002/nag.1124
6	M R Coop, K K Sorensen, T Bodas Freitas, G Georgoutsos. Particle breakage during shearing of a carbonate sand. Geotechnique, 2004, 54(3): 157–163 https://doi.org/10.1680/geot.2004.54.3.157
7	I Cavarretta, M R Coop, C O’Sullivan. The influence of particle characteristics on the behaviour of coarse grained soils. Geotechnique, 2010, 60(6): 413–423 https://doi.org/10.1680/geot.2010.60.6.413
8	K Senetakis, M R Coop. Micro-mechanical experimental investigation of grain-to-grain sliding stiffness of quartz minerals. Experimental Mechanics, 2015, 55(6): 1187–1190 https://doi.org/10.1007/s11340-015-0006-4
9	P A Cundall, O D Strack. A discrete numerical model for granular assemblies. Geotechnique, 1979, 29(1): 47–65 https://doi.org/10.1680/geot.1979.29.1.47
10	K Iwashita, M Oda. Rolling resistance at contacts in simulation of shear band development by DEM. Journal of Engineering Mechanics, 1998, 124(3): 285–292 https://doi.org/10.1061/(ASCE)0733-9399(1998)124:3(285)
11	M J Jiang, H S Yu, D Harris. A novel discrete model for granular material incorporating rolling resistance. Computers and Geotechnics, 2005, 32(5): 340–357 https://doi.org/10.1016/j.compgeo.2005.05.001
12	B Zhou, R Huang, H Wang, J Wang. DEM investigation of particle anti-rotation effects on the micromechanical response of granular materials. Granular Matter, 2013, 15(3): 315–326 https://doi.org/10.1007/s10035-013-0409-9
13	T Matsushima, H Saomoto. Discrete element modeling for irregularly-shaped sand grains. In: Proc. NUMGE2002: Numerical Methods in Geotechnical Engineering, 2002, 239–246
14	M Price, V Murariu, G Morrison. Sphere clump generation and trajectory comparison for real particles. In: Proceedings of Discrete Element Modelling, 2007
15	J Ferellec, G McDowell. Modelling realistic shape and particle inertia in DEM. Geotechnique, 2010, 60(3): 227–232 https://doi.org/10.1680/geot.9.T.015
16	T T Ng. Fabric study of granular materials after compaction. Journal of Engineering Mechanics, 1999, 125(12): 1390–1394 https://doi.org/10.1061/(ASCE)0733-9399(1999)125:12(1390)
17	P W Cleary. The effect of particle shape on simple shear flows. Powder Technology, 2008, 179(3): 144–163 https://doi.org/10.1016/j.powtec.2007.06.018
18	M. Oda Initial fabrics and their relations to mechanical properties of granular material. Soils and Foundations, 1972, 12(1): 17–36
19	K Konagai, C Tamura, P Rangelow, T Matsushima. Laser-aided tomography: A tool for visualization of changes in the fabric of granular assemblage. Structural Engineering/Earthquake Engineering, 1992, 9(3): 193–201 (in Japanese)
20	R A Johns, J S Steude, L M Castanier, P V Roberts. Nondestructive measurements of fracture aperture in crystalline rock cores using X ray computed tomography. Journal of Geophysical Research. Solid Earth, 1993, 98(B2): 1889–1900 https://doi.org/10.1029/92JB02298
21	T Ohtani, T Nakano, Y Nakashima, H Muraoka. Three-dimensional shape analysis of miarolitic cavities and enclaves in the Kakkonda granite by X-ray computed tomography. Journal of Structural Geology, 2001, 23(11): 1741–1751 https://doi.org/10.1016/S0191-8141(01)00033-5
22	M Oda, T Takemura, M Takahashi. Microstructure in shear band observed by microfocus X-ray computed tomography. Geotechnique, 2004, 54(8): 539–542 https://doi.org/10.1680/geot.2004.54.8.539
23	J Fonseca, C O’Sullivan, M R Coop, P D Lee. Quantifying the evolution of soil fabric during shearing using directional parameters. Geotechnique, 2013, 63(6): 487–499 https://doi.org/10.1680/geot.12.P.003
24	J Fonseca, C O’Sullivan, M R Coop, P D Lee. Quantifying the evolution of soil fabric during shearing using scalar parameters. Geotechnique, 2013, 63(10): 818–829 https://doi.org/10.1680/geot.11.P.150
25	J Desrues, R Chambon, M Mokni, F Mazerolle. Void ratio evolution inside shear bands in triaxial sand specimens studied by computed tomography. Geotechnique, 1996, 46(3): 529–546 https://doi.org/10.1680/geot.1996.46.3.529
26	N Lenoir, M Bornert, J Desrues, P Bésuelle, G Viggiani. Volumetric digital image correlation applied to X-ray micro tomography images from triaxial compression tests on argillaceous rock. Strain, 2007, 43(3): 193–205 https://doi.org/10.1111/j.1475-1305.2007.00348.x
27	Y Watanabe, N Lenoir, J Otani, T. Nakai Displacement in sand under triaxial compression by tracking soil particles on X-ray CT data. Soils and foundations, 2012, 52(2): 312–320
28	T Matsushima, J Katagiri, K Uesugi, T Nakano, A Tsuchiyama. Micro X-ray CT at Spring-8 for granular mechanics. In: Soil Stress-Strain Behavior: Measurement, Modeling and Analysis: A Collection of Papers of the Geotechnical Symposium in Rome. 2006, 146: 225–234
29	J Otani, T Mukunoki, Y Obara. Characterization of failure in sand under triaxial compression using an industrial X-ray CT scanner. International Journal of Physical Modelling in Geotechnics, 2002, 2(1): 15–22 https://doi.org/10.1680/ijpmg.2002.020102
30	A Hasan, K Alshibli. Three dimensional fabric evolution of sheared sand. Granular Matter, 2012, 14(4): 469–482 https://doi.org/10.1007/s10035-012-0353-0
31	E Andò. Experimental investigation of microstructural changes in deforming granular media using X-ray tomography. Dissertation for the Doctoral Degree. Grenoble: The University of Grenoble, 2013
32	Y Higo, F Oka, T Sato, Y Matsushima, S Kimoto. Investigation of localized deformation in partially saturated sand under triaxial compression using microfocus X-ray CT with digital image correlation. Soil and Foundation, 2013, 53(2): 181–198 https://doi.org/10.1016/j.sandf.2013.02.001
33	Y Higo, F Oka, S Kimoto, T Sanagawa, Y. Matsushima Study of strain localization and microstructural changes in partially saturated sand during triaxial tests using microfocus X-ray CT. Soils and Foundations, 2011, 51(1): 95–111
34	K H Head. Manual of Soil Laboratory Testing. London: Pentech Press Ltd., 1982
35	B Indraratna, L S S Wijewardena, A S Balasubramaniam. Large-scale triaxial testing of greywacke rockfill. Geotechnique, 1993, 43(1): 37–51 https://doi.org/10.1680/geot.1993.43.1.37
36	J Wang, M Gutierrez. Discrete element simulations of direct shear specimen scale effects. Geotechnique, 2010, 60(5): 395–409 https://doi.org/10.1680/geot.2010.60.5.395
37	J Desrues, E Andò, F A Mevoli, L Debove, G Viggiani. How does strain localise in standard triaxial tests on sand: Revisiting the mechanism 20 years on. Mechanics Research Communications, 2018, 92: 142–146 https://doi.org/10.1016/j.mechrescom.2018.08.007
38	S A Hall, M Bornert, J Desrues, Y Pannier, N Lenoir, G Viggiani, P Bésuelle. Discrete and continuum analysis of localised deformation in sand using X-ray CT and volumetric digital image correlation. Geotechnique, 2010, 60(5): 315–322 https://doi.org/10.1680/geot.2010.60.5.315
39	E Andò, G Viggiani, S A Hall, J Desrues. Experimental micro-mechanics of granular media studied by X-ray tomography: Recent results and challenges. Géotechnique Letters, 2013, 3(3): 142–146 https://doi.org/10.1680/geolett.13.00036
40	I Vlahinić, R Kawamoto, E Andò, G Viggiani, J E Andrade. From computed tomography to mechanics of granular materials via level set bridge. Acta Geotechnica, 2017, 12(1): 85–95 https://doi.org/10.1007/s11440-016-0491-3
41	Z Cheng, J Wang. Experimental investigation of inter-particle contact evolution of sheared granular materials using X-ray micro-tomography. Soils and Foundations. 2018, 58(6): 1492–1510
42	B D Zhao, J F Wang, M R Coop, G Viggiani, M J Jiang. An investigation of single sand particle fracture using X-ray micro-tomography. Geotechnique, 2015, 65(8): 625–641 https://doi.org/10.1680/geot.4.P.157
43	W Y Wang, M R Coop. An investigation of breakage behaviour of single sand particles using a high-speed microscope camera. Geotechnique, 2016, 66(12): 984–998 https://doi.org/10.1680/jgeot.15.P.247
44	P Perona, J Malik. Scale-space and edge detection using anisotropic diffusion. IEEE Transactions on Pattern Analysis and Machine Intelligence, 1990, 12(7): 629–639 https://doi.org/10.1109/34.56205
45	D Bernard, O Guillon, N Combaret, E Plougonven. Constrained sintering of glass films: Microstructure evolution assessed through synchrotron computed microtomography. Acta Materialia, 2011, 59(16): 6228–6238 https://doi.org/10.1016/j.actamat.2011.06.022
46	R Al-Raoush, K A Alshibli. Distribution of local void ratio in porous media systems from 3D X-ray microtomography images. Physica A, 2006, 361(2): 441–456 https://doi.org/10.1016/j.physa.2005.05.043
47	Z Cheng. Investigation of the grain-scale mechanical behavior of granular soils under shear using X-ray micro-tomography. Dissertation for the Doctoral Degree. Hong Kong, China: City University of Hong Kong, China, 2018
48	S Beucher, C Lantuejoul. Use of watersheds in contour detection. In: Proceedings of the International Workshop on image Processing, Real-Time Edge and Motion Detection/Estimation. Rennes, 1979
49	R C Gonzalez, R E Woods. Digital Image Processing. Upper Saddle River, NJ: Pearson/Prentice Hall, 2010
50	Z Cheng, J Wang. A particle-tracking method for experimental investigation of kinematics of sand particles under triaxial compression. Powder Technology, 2018, 328: 436–451 https://doi.org/10.1016/j.powtec.2017.12.071
51	Z Cheng, J Wang. Quantification of the strain field of sands based on X-ray micro-tomography: A comparison between a grid-based method and a mesh-based method. Powder Technology, 2019, 344: 314–334 https://doi.org/10.1016/j.powtec.2018.12.048

[1]	Yuanqing ZHU , Zhenghan CHEN , . A new method of studying collapsibility of loess[J]. Front. Struct. Civ. Eng., 2009, 3(3): 305-311.

Viewed

Full text

Abstract

Cited

Shared

Discussed