| Widely graded gravel soils have many advantages such as low cost, low compressibility, low permeability, and high shearing strength etc. To date, widely graded gravel soils have been used in the anti-seepage control of embankment, dam, landfill and channel. Even some researches have been carried out, the knowledge for the compaction and permeability of widely graded gravel soil and its design codes are still incomplete.To tap the anti-seepage potential of widely graded gravel and build the design codes, laboratory tests are first carried out in this research which including sieving tests, compaction tests and permeability tests for gravel soils with various fine contents. Further, the anti-seepage performance of gravel soils is assessed using Finite Element Method (FEM). The following findings have been achieved:(1) The grading of wide grading gravel soil is suggested to be measured by wet sieving method because the dry sieving method has great errors;(2) A prediction model of optimum moisture content for gravel soil is gained and verified by tests;(3) Grading control standard for permeability of gravel soil is obtained:(4) Permeability coefficients of cemented and bentonite gravelly soils is measured and the recommended values of cement and bentonite doping is given out;(5) Based on the results of numerical simulation, the gravelly soil layer can be used for landfill liner is demonstrated, and the concrete scheme is given.The findings obtained in this study can be used to guide the anti-seepage practices in geotechnical engineering. |
