Abstract—The mechanical properties of granular materials such as loading and deformation resistance are closely related to the microstructure of the material. A FEM simulation work on random diameter size particle system along with the loading process of vertical compression and the transverse shear are carried out in this paper. The contact force chain and the load bearing skeleton in particle system are observed under the compressed and shear load while the results of numerical simulation is verified by a photo-elastic test. The results from numerical simulation and photo-elastic test shows that the force chains grows up gradually until a stable load bearing skeleton formed in loading process. With the load of threshold value reached or bearing direction changed, the load bearing skeleton would go to instability and collapsed rapidly. The results also show stress fluctuation in granular material on macro-scale. The load bearing skeleton in particle system has obvious directivity and if the bearing direction is changed it will quickly lead to the skeleton failure. The fabric tensor is considered to express a bulk stress on granular material. This paper also studies the stability of load bearing skeleton with different friction between particles. 
 

Index Terms—granular material, micro-structure, load bearing direction, force chain, orthotropic

Cite: Mohammad Alam, Zhengguo Gao, and Zhichang Li, "Study on the Microstructure and Load Bearing Properties of Granular Material," International Journal of Structural and Civil Engineering Research, Vol. 5, No. 3, pp. 196-200, August 2016. doi: 10.18178/ijscer.5.3.196-200