Graded Filter

Filter, Graded

 

a device in headworks that consists of several layers of unconsolidated material with increasingly coarse particles in each layer. The material may be sand, gravel, rubble, or pebbles; the coarseness of the particles increases toward the seepage line. Graded filters are used mainly in earth dams and other hydraulic-engineering installations erected on soft foundations. Such filters prevent seepage from washing fine soil particles from the body and base of the installation.

Mentioned in ?
References in periodicals archive ?
Once dosed, effluent passes through 6 inches of rock and 2 feet of graded filter sand before being collected by three 1,200 gallon pump tanks connected to form one 3,600-gallon pump chamber.
nttps ash pond strengthening of bund by providing sand filter, graded filters, rock toe and gravel cover on down stream side of the earthen bund from rock toe to the berm at el(+) 40m from ch.