Recent progress on crushing-strength-energy dissipation of coarse granular soil and biocementation at contacts

Abstract

Coarse granular soil is widely used in infrastructures, such as hydropower dams, road and railways beds and airport high-fill slopes, which have high requirements of strength and deformation. Coarse granular soil has larger particle size and more scattered particle strength than other granular geomaterials. The particles of coarse granular soil are easy to break when subjected to external loading. Biocementaion, as a new promising green technology, has a potential to improve mechanical properties and alleviate particle breakage of coarse granular soil. This review introduce relevant theoretical analysis methods of particle strength of coarse granular soils first, including Weibull distribution, size effect, fractal dimension, avalanche dynamics, etc. Then, laboratory testing technique to investigate the particle strength and deformation characteristics is also introduced, e.g., single-particle crushing test, one-dimensional compression test, acoustic emission monitoring system and biocementation technology, etc. Finally, results of single-particle crushing test and one-dimensional compression test of coarse granular soil are summarized and analyzed to examine the effects of material properties, external environmental factors, particle size, and biocementation conditions on particle strength, Weibull modulus, compressibility, crushing amount, acoustic emission energy and energy dissipation, etc. This work will deepen the understanding of the particle strength and deformation characteristics of coarse granular soil and promote the application of coarse granular soil in practical engineering.