Coefficient of consolidation for clays normally A. decreases with increase in liquid limit B. increases with increase in liquid limit C. first increases and then decreases with increase in liquid limit D. remains constant at all liquid limits

decreases with increase in liquid limit
increases with increase in liquid limit
first increases and then decreases with increase in liquid limit
remains constant at all liquid limits

The correct answer is A. decreases with increase in liquid limit.

The coefficient of consolidation is a measure of how quickly a soil consolidates, or compresses, under load. It is a function of the soil’s permeability and the effective stress. The effective stress is the difference between the total stress and the pore water pressure.

The liquid limit is a measure of the soil’s plasticity. It is the water content at which the soil changes from a solid to a liquid state. Clays with a high liquid limit are more plastic and have a lower coefficient of consolidation than clays with a low liquid limit.

This is because clays with a high liquid limit have a higher water content and a lower effective stress. The higher water content makes it more difficult for the soil to consolidate, and the lower effective stress means that the soil is not as strongly compacted.

As the liquid limit increases, the soil becomes more plastic and has a lower coefficient of consolidation. This means that it takes longer for the soil to consolidate under load.

The coefficient of consolidation is an important parameter in geotechnical engineering. It is used to calculate the settlement of foundations and other structures.