Reply to “Discussion of ‘Experimental investigation of shear strength of sands with inherent fabric anisotropy’ by Tong et al. (DOI 10.1007/s11440-014-0303-6)” by Gao (DOI 10.1007/s11440-015-0383-y)

Abstract

The authors read with interest the discussion of their paper by Dr. Zhiwei Gao. The discusser correctly points out that a general failure criterion without a priori knowledge of the failure plane can be used in general analysis, while a criterion addressing failure at a specific plane is more restricted. However, the latter criterion is more practical for problems where the failure plane is known, and its parameters can be directly determined by the direct shear test which is relatively easy to perform. It must be pointed out that our paper does not propose such a criterion explicitly, but it lays down the experimental evidence and foundation for such a possible proposition. Having said that, we pleasantly notice that the simulations of the model of the discusser agree with, in every aspect examined, our experimental data, both the ones obtained earlier by DEM [1] and the ones on real sand samples of the paper under discussion. It should be mentioned that the model used by the discusser is based on the recently developed Anisotropic Critical State Theory (ACST) by Li and Dafalias [2] that brings into the picture the role of fabric on the response of granular media, and enhances the classical Critical State Theory (CST) by one more condition on the critical state value of the fabric (in fact Y. F. Dafalias is a co-author of that paper that develops the model). There are a few additions to the brief presentation that may interest the soil modeling community. We hope the discusser may consider these in the future.