Question

1.17 Permeability of geotextiles refers to liquid moving through the voids created by the fibers and yarns that make up the fabric. This permeability is called “Darcian permeability."

Answer 1

Solution is attached in the image posted below.

Various terms has been identified with formula itself.

All the factor which makes permeability to vary have been mentioned.

can Doucy's lawi- there is a lineas It suggest that Relationship between velocity of flow and hydraulic Gradient. va v=ki where V = velocity of flow Toischarge velocity] î = hydraulic Chradien. for laminar flow the discharge from. an cuea per unit time is equal to propotional to hychaulic Gradient q a q= Discharge Per unit time = Cross sectional Сиea ob Дост Mass ů = hyonaulic Gradient A K = coefficient of Permeability (c) fac-or abbech пе қvouse , ohел е Kis coefficient of permeability as stated above А q=ki [q=kia

0 Grain size K= C [Dio)? Dio effective dia of grair below which 10 percent particle falls. o Pore fluid & there properties:- of unit weight of fluid in pores is greater then it will have highes Permeability whereas if viscosity increases ob pore fluid then pameat bility cleaeases ③ Temperatue: viscosity cleaease with temperatue of fluid nence increase in temperature increases Permeability. void Ratio: with incement in void Ratio permeability increaser. © Stratification ob sil! of soil is in layer and water is to be passes through it permeabi- wty is max for flow perpendicular to bed whereas minimum when flow is Parallel to bed 6 Entrapped air and organic impurity Reduces permeability Adsorbed water: Reduces pore Space in twin Reduces permeability

greater & Degree of batwalioni fully satmated coil has permeability @ shape of particles permeability is imvesely Чо ѕресi bic Блшосе popot