Study on gravelly soil as impermeable material of earth dam

The study on gravelly soil as impermeable material shows that the seepage coefficient of gravelly soil fully satisfies the requirements of earth dam when the contents of gravel(>5 mm) and fine grain (<0.074 mm) after compaction are limited within a critical value,and that their dry densities are fully influ enced by their parent rock properties and weathered degree In addition,an empirical formula for maximum dry density of gravelly soil is put forward.