Shen, X.; Zhang, M.; Zhang, J., and Yan, H., 2015. Development on measuring device of seepage coefficient for super-size coarse-grained soil.

Lots of super-size coarse-grained soil was distributed along the central line of the Water Diversion Project from South to North in China, the diameter of soil grain exceeded the measuring range of existing devices for seepage coefficient of coarse-grained soil. Special measuring device is developed, canister diameter of measurement is increased; accelerated exhaust method is carried out; grading increasing method of seepage gradient is used, and corresponding method of test is carried out. The test shows that the adaptable range of character diameter value (d₈₅) of soil grain is from 60 mm to 100 mm, and accelerated exhaust method overcomes some problems which are bigger in diameter of specimen, lower in penetrability of materials, more difficult in saturation of specimen and so on, and grading increasing method of seepage gradient decreases destruction of specimen. The technique can be used in penetrability test and detection of project quality for super-size coarse-grained soil.