Generation of 3D random meso-structure of soil-rock mixture and its meso-structural mechanics based on numerical tests

Abstract

The mesoscopic failure mechanism and the macro-mechanical characteristics of soil-rock mixture (S-RM) under external load are largely controlled by S-RM’s meso-structural features. The objective of this work is to improve the three-dimensional technology for the generation of the random meso-structural models of S-RM, for randomly generating irregular rock blocks in S-RM with different shapes, sizes, and distributions according to the characteristics of the rock blocks’ size distribution. Based on the new improved technology, a software system named as R-SRM^3D for generation and visualization of S-RM is developed. Using R-SRM^3D, a three-dimensional meso-structural model of S-RM is generated and used to study the meso-mechanical behavior through a series of true-triaxial numerical tests. From the numerical tests, the following conclusions are obtained. The meso-stress field of S-RM is influenced by the distribution of the internal rock blocks, and the macro-mechanical characteristics of S-RM are anisotropic in 3D; the intermediate principal stress and the soil-rock interface properties have significant influence on the macro strength of S-RM.

Keywords

soil-rock mixture (S-RM) / three dimensional meso-structure / meso-structural mechanics (M-SM) / true-triaxial numerical test / random simulation

References

[1] ArasanS, HasilogluA S, AkbulutS. Shape properties of natural and crushed aggregate using image analysis [J]. International Journal of Civil & Structural Engineering, 2010, 1(2): 221-233

[2] ArasanS, YeneraE, HattatogluF, HinisliogluaS, AkbulutaS. Correlation between shape of aggregate and mechanical properties of asphalt concrete: digital image processing approach [J]. Road Materials and Pavement Design, 2011, 12(2): 239-262

[3] XuW-j, YueZ-q, HuR-lin. Study on the meso-structure and meso-mechanical characteristics of the soil-rock mixture using digital image processing based finite element method [J]. International Journal of Rock Mechanics and Mining Sciences, 2008, 45(5): 749-762

[4] MasadE, MuhunthanB, ShashidharN, HarmanT. Internal structure characterization of asphalt concrete using image analysis [J]. Journal of Computing in Civil Engineering, 1999, 13(2): 88-95

[5] XuW-j, HuR-l, WangY-ping. PFC2D model for mesostructure of inhomogeneous geomaterial based on digital image processing [J]. Journal of China Coal Society, 2007, 32(4): 358-362

[6] ColiN, BerryP, BoldiniD. In situ non-conventional shear tests for the mechanical characterisation of a bimrock (BimTest) [J]. International Journal of Rock Mechanics and Mining Science, 2011, 48(1): 95-102

[7] ColiN, BerryP, BoldiniD, BrunoD. The contribution of geostatistics to the characterisation of some bimrock properties [J]. Engineering Geology, 2012, 137/138: 53-63

[8] XuW X, ChenH S. Microstructural characterization of fresh cement paste via random packing of ellipsoidal cement particles. Materials Characterization, 2012, 66: 16-23

[9] LiY P, HuangG H. Dual-interval fuzzy stochastic programming method for long-term planning of municipal solid waste management [J]. Journal of Computing in Civil Engineering, 2010, 24(2): 188-202

[10] Merrien-SoukatchoffV, KoriniT, ThoravalA. Use of an integrated discrete fracture network code for stochastic stability analysis of fractured rock massed [J]. Rock Mechanics and Rock Engineering, 2012, 45(2): 159-181

[11] XuX-j, ZhangX-ning. Crack detection of reinforced concrete bridge using video image [J]. Journal of Central South University, 2013, 20(9): 2605-2613

[12] WangZ M, KwanA K H, ChanC H. Mesoscopic study of concrete I: Generation of random aggregate structure and finite element mesh [J]. Computers and Structure, 1999, 70(5): 533-544

[13] XuW-x, ChenH-s, LvZhong. A 2d elliptical model of random packing for aggregates in concrete [J]. Journal of Wuhan University of Technology: Mater Sci Ed, 2010, 25(4): 717-720

[14] YouX-huaStochastic structural model of the earth-rock aggregate and its application [D], 2001, Beijing, Northern Jiaotong University

[15] XuW-j, HuR-l, YueZ-qi. Development of random meso-structure generating system of soil-rock mixture and study of its meso-structural mechanics based on numerical test [J]. Chinese Journal of Rock Mechanics and Engineering, 2009, 28(8): 1652-1665

[16] DuC-b, SunL-guo. Numerical simulation of concrete aggregates with arbitrary shapes and its application [J]. Journal of Hydraulic Engineering, 2006, 37(6): 662-667

[17] ChenJ, PanT-y, HuangX-ming. Numerical investigation into the stiffness anisotropy of asphalt concrete from a microstructural perspective [J]. Construction and Building Materials, 2011, 25(7): 3059-3065

[18] LiuY, YouZ-ping. Visualization and simulation of asphalt concrete with randomly generated three-dimensional models [J]. Journal of Computing in Civil Engineering, 2009, 23: 340-347