Permeability
1. For clay soils, soils with greater void ratios have ____ permeability.
2. Due to a change in temperature, the viscosity (μ) of the liquid is reduced by 40%. What is the change in the permeability of the soil?
3. A soil is considered 'impermeable' for most practical engineering purposes if its K (cm/sec) value is less than:
4. Coefficient of permeability is also called as which of the following?
5. Seepage velocity (vs) is related to discharge velocity (v) and porosity (n) by the formula:
6. In a stratified soil deposit, the equivalent permeability for flow parallel to the layers (kx) compared to flow perpendicular to the layers (kz) is generally:
7. A constant head permeability test on a medium soil sample having a cross sectional area (A) of 7585 mm² yielded the following data: Distance between stand-pipes (L) = 100 mm, Constant head difference (h) = 70.4 mm, Quantity of water collected (Q) = 500 * 10³ mm³, Time of collection (t) = 132 s. Determine the coefficient of permeability of the specimen.
8. In a falling head permeability test, a soil sample of 7585 mm² cross-section (A) and 210.2 mm length (L) was subjected to a flow of water from a stand-pipe having cross-sectional area (a) of 730 mm². The stand-pipe level changed from 1650 mm (h1) to 550 mm (h2) during a time interval (t) of 182 sec. Determine the coefficient of permeability.
9. If the coefficient of permeability (k) of a soil is 10⁻⁵ cm/s at 20°C, what would be the approximate permeability at 30°C? (Assume viscosity at 20°C = 1.0 mPa·s and at 30°C = 0.8 mPa·s)