Engineering properties of the compressibility and crushing characteristics of transitional soils mixed with silicate and carbonate sands

Abstract Transitional soils mixed with terrestrial silicate and marine carbonate deposits are commonly found in coastal regions, which have special geological and geotechnical characteristics. This study examines the engineering properties of the compressibility and crushing characteristics of this type of transitional silicate‑carbonate soils. Scanning Electron Micrograph, X-ray fluorescence and laboratory tests were first conducted to identify the physical and mechanical properties of the pure silicate and carbonate soil samples adopted in this study. A total of 54 one dimensional compression tests were carried out for soil samples mixed with varying portion of silicate and carbonate sands by applying increasing loading level, where particle size distribution was obtained post each test to quantify particle breakage. The soil deformation is found to comprise two components that are caused by inter-particle rearrangement and particle breakage. The test results show that particle breakage tends to play a dominant role on the deformation with increasing content of carbonate sand and load level. The series of laboratory tests and the associated interpretations in this paper are expected to provide an improved understanding of the compressibility and crushing characteristics of transitional sediments mixed with silicate and carbonate sands. An equation was proposed to establish the relationship between particle breakage and crushing work, which provides a predictive assessment of particle breakage for transitional soils accounting for varying portion of silicate and carbonate sands.