What is the primary factor that determines soil classification?
A Color
B Texture
C Moisture content
D Strength
Soil classification is primarily based on texture, which refers to the proportions of sand, silt, and clay in the soil. This determines how soil behaves in terms of drainage, compaction, and stability.
What does permeability of soil refer to?
A Ability to resist deformation
B Ability to retain water
C Ability to compact
D Ability to transmit water
Permeability is the ability of soil to transmit water or other fluids through its pores. It depends on the size and connectivity of soil particles. Sands typically have high permeability, while clays have low permeability.
The Atterberg limits are used to classify which type of soil?
A Clay
B Sand
C Silt
D Gravel
The Atterberg limits are used to determine the consistency of clay soils. They include the liquid limit, plastic limit, and shrinkage limit, which help classify soils based on their moisture content and behavior under different conditions.
Which test is commonly used to determine the shear strength of soil?
A Plate load test
B Proctor test
C Triaxial test
D CBR test
The triaxial test is widely used to determine the shear strength of soil. It involves applying stress to a soil sample in a controlled environment to measure its response and failure point, providing insights into its shear strength.
What does consolidation of soil refer to?
A Soil shrinkage under load
B Soil settling due to pressure
C Water flow through soil
D Soil compaction
Consolidation refers to the process by which soil gradually decreases in volume over time under the application of sustained load, typically caused by the expulsion of pore water. This is a critical factor in soil settlement analysis.
Which soil property is most important for determining bearing capacity?
A Cohesion
B Permeability
C Plasticity
D Shrinkage
Bearing capacity of soil refers to the maximum load per unit area the soil can support without failure. Cohesion, which is the attractive force between soil particles, plays a significant role in determining bearing capacity.
What is the purpose of the Standard Proctor Test?
A Determine soil classification
B Analyze consolidation rate
C Determine optimal moisture content for compaction
D Measure shear strength
The Standard Proctor Test is used to find the optimum moisture content at which a soil type can achieve maximum compaction. This ensures the soil achieves its highest density and strength when compacted.
What is the main cause of soil erosion?
A High soil permeability
B Water and wind action
C Soil shrinkage
D Low compaction
Soil erosion is primarily caused by water and wind that move soil particles from one location to another. Over time, erosion can degrade soil quality and lead to loss of fertile topsoil.
What is the role of geotextiles in soil mechanics?
A Enhance soil strength
B Prevent water flow
C Increase plasticity
D Drainage and filtration
Geotextiles are synthetic fabrics used in soil applications to provide drainage, filtration, and separation of soil layers. They help control erosion and improve the stability of soil structures.
In soil mechanics, what does effective stress mean?
A Stress caused by water pressure
B Stress from soil weight
C Total stress minus pore water pressure
D Stress from external load
Effective stress is the stress that contributes to soil strength and is calculated by subtracting the pore water pressure from the total stress. It governs the shear strength of soils, especially in saturated conditions.
What is the primary purpose of a plate load test?
A Assess bearing capacity of soil
B Measure soil compaction
C Determine soil permeability
D Test shear strength of soil
The plate load test is used to assess the bearing capacity of soil, especially for foundation design. It involves applying a load to a rigid plate placed on the soil surface and measuring the resulting settlement.
Which of the following affects soil compaction the most?
A Particle size
B Moisture content
C Soil color
D Soil temperature
Moisture content significantly affects soil compaction. When moisture is added to soil, it helps particles move closer together, increasing the soil’s density. Too much or too little moisture can reduce compaction efficiency.
Liquefaction in soils occurs mainly during what type of event?
A Flooding
B Heavy rainfall
C Soil freezing
D Earthquake
Liquefaction occurs when saturated soils lose their strength and behave like a liquid during an earthquake. The shaking causes pore water pressure to increase, reducing soil’s ability to support loads, leading to potential structural damage.
What is the main characteristic of swelling soils?
A They shrink when wet
B They become more compacted over time
C They expand when wet
D They are very stable
Swelling soils, especially those containing expansive clay minerals, increase in volume when they absorb water. This can cause significant issues for foundations and structures built on such soils, requiring special treatment.
What is the purpose of soil stabilization?
A Improve soil’s strength and durability
B Increase soil temperature
C Decrease soil permeability
D Remove moisture from soil
Soil stabilization refers to processes that improve the physical properties of soil, such as its strength and durability. Methods may include adding chemicals or using mechanical techniques to prevent erosion and enhance compaction.