Abstract: In order to obtain force chains of the granular matter in 3D quantitatively, numerical simulations of discrete element method are conducted on a compressed and sheared system consisting of 7200 particles. Its found that the number of force chains decrease in an exponential form, whose exponent is the length of the chains. Meanwhile the constants used to fit the exponential law can be explained in the view of probability. Although the number of the chains varies greatly during the simulations, the exponential law is unchanged with a correlation coefficient greater than 0.99. The results are in line with experimental data. Furthermore, the method of extracting force chains can not only analyze chains’ breaking and recombining, but also be extended to displacement chains and shear chains as well.

Key words: granular matter, force chain, exponential law