Behavior of sand-rubber particle mixtures: experimental observations and numerical simulations

• Published in: International journal for numerical and analytical methods in geomechanics Vol. 38; no. 16; pp. 1651 - 1663
• Main Authors: Lee, Changho, Shin, Hosung, Lee, Jong-Sub
• Format: Journal Article
• Language: English
• Published: Chichester Blackwell Publishing Ltd 01.11.2014; Wiley; Wiley Subscription Services, Inc
• Subjects: Anisotropy; Applied sciences; Buildings. Public works; compressibility; Computer simulation; Contact angle; DEM; Exact sciences and technology; Geotechnics; Inclusions; Mathematical models; Rubber; Sand; sand-rubber mixture; shear modulus; Soil investigations. Testing; Strain; strain level; strength; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; transition; Compressibility; Sand; Shear modulus; Stress strain relation; sand-rubber mixture; Property of soil; Discrete element method; K; Experimental study; DEM; Mixture; transition; strain level; Soil test; Behavior; Rubber; Strength
• ISSN: 0363-9061; 1096-9853
• DOI: 10.1002/nag.2264

SUMMARY A series of laboratory experiments and numerical simulations are conducted to explore the characteristics of mixtures composed of sand and rubber particles of the same median diameter. The mixtures are prepared with different volumetric sand fractions (sf = Vsand/Vtotal). The experiment focuses on assessing the strain level on the characteristics of the mixture with the volume fraction of each component. Numerical simulations using the discrete element method are performed to obtain insight into the microscale behavior and internal mechanism of the mixtures. The experimental results show that the behavior of the mixtures is dependent on the relative sand and rubber particles composition with variation in the strain levels. The numerical simulation reveals the effect of the soft rubber particle inclusion in the mixture on the micromechanical parameters. In low sand fraction mixtures, a high shear stress along the contact is mobilized, and the stress state is driven to a more anisotropic condition because of the relatively high particle friction angle of the rubber. The rubber particles play different roles with the strain level in the mixture, including increasing the coordination number and controlling plasticity of the mixture in a small strain, preventing buckling of the force chain in an intermediate strain, and leading to contractive behavior in a large strain. Copyright © 2014 John Wiley & Sons, Ltd.