How does the presence of a high water table affect the bearing capacity of soil?
Practice Questions
Q1
How does the presence of a high water table affect the bearing capacity of soil?
Increases bearing capacity
Decreases bearing capacity
No effect
Depends on soil type
Questions & Step-by-Step Solutions
How does the presence of a high water table affect the bearing capacity of soil?
Step 1: Understand what a water table is. The water table is the level below which the ground is saturated with water.
Step 2: Know what bearing capacity means. Bearing capacity is the ability of soil to support the weight of structures built on it.
Step 3: Learn about effective stress. Effective stress is the stress that contributes to the strength of the soil, which is the total stress minus the pore water pressure.
Step 4: Recognize that a high water table means more water in the soil. This increases the pore water pressure.
Step 5: Realize that when pore water pressure increases, the effective stress decreases. This is because effective stress = total stress - pore water pressure.
Step 6: Understand that lower effective stress means the soil is weaker and can support less weight.
Step 7: Conclude that a high water table can reduce the bearing capacity of the soil, making it less able to support structures.
Effective Stress Principle – The effective stress in soil is the difference between the total stress and pore water pressure, which influences the soil's strength and bearing capacity.
Bearing Capacity – The maximum load per unit area that the soil can support without failure.
High Water Table Effects – A high water table increases pore water pressure, reducing effective stress and thus decreasing bearing capacity.
