Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Which of the following soil is highly permeable?
gravel
sand
clay
silt
gravel
Gravel is highly permeable because it consists of coarse-grained particles with large interconnected voids. These large pore spaces allow water to flow through the soil matrix with minimal resistance compared to finer soils like silt or clay.
Gravel is highly permeable because it consists of coarse-grained particles with large interconnected voids. These large pore spaces allow water to flow through the soil matrix with minimal resistance compared to finer soils like silt or clay.
k=CтЛЕD102тАЛ тАФ Hazen's formula relating permeability to particle size (D10тАЛ)
v=kтЛЕi тАФ Darcy's Law representing discharge velocity
According to Darcy's Law, the coefficient of permeability (k) is directly proportional to the square of the grain size (D2) and inversely proportional to the viscosity of the fluid. In gravel, the average grain size is significantly larger than in other soil types, leading to a much higher value of k and allowing rapid drainage.
Gravel has the highest permeability among common soil types.
Permeability is highly dependent on the effective size (D10тАЛ) of soil particles.
Clay has the lowest permeability due to its very fine particles and high surface area.
Void ratio and particle shape also influence the flow characteristics.
Excellent drainage characteristics
High structural stability under drained conditions
Prone to erosion due to high flow velocity
Difficult to retain in place without filter materials
Base courses for road construction
Drainage blankets and filters
Sub-surface drainage systems
| Feature | Permeable | Impermeable |
|---|---|---|
Soil Type | Gravel | Clay |
The permeability of gravel is typically >1.0┬аcm/s.
Option B (Sand) is permeable but less than gravel; Option C (Clay) is practically impermeable; Option D (Silt) has low permeability.
A is correct тАФ Gravel is highly permeable due to its coarse-grained structure and large interconnected void spaces.
Always remember that permeability follows the order: Gravel > Sand > Silt > Clay, which is inversely proportional to the specific surface area of the soil particles.