Consistency Limits – Behavior Beyond the Shrinkage Limit If a fine-grained soil is dried further after reaching its shrinkage limit, what volumetric behavior will it exhibit?

Introduction / Context:
Atterberg limits define the boundaries between consistency states of fine-grained soils. The shrinkage limit marks the moisture content at which further drying does not cause additional volume decrease. Understanding this behavior is essential for predicting volumetric stability of clays and silts in drying environments.

Given Data / Assumptions:

• Soil: fine-grained (plastic) soil.
• Condition: water content has reached the shrinkage limit.
• Process: further drying beyond this limit.

Concept / Approach:

Between the liquid and plastic limits, soil transitions from viscous to plastic behavior. From plastic to semi-solid, the soil stiffens and shrinks as water is expelled. At the shrinkage limit, the soil attains a structure in which voids cannot collapse further without breaking the soil skeleton; the volume becomes essentially constant even if more water is removed.

Step-by-Step Solution:

Verification / Alternative check:

Shrinkage limit tests typically plot volume versus water content showing a linear reduction up to the limit, followed by a flat plateau beyond the limit, confirming no additional shrinkage.

Why Other Options Are Wrong:

• Large/moderate/low volume change: These imply continued shrinkage, which contradicts the very definition of the shrinkage limit.

Common Pitfalls:

Confusing shrinkage limit with plastic limit; assuming microcracking always causes measurable bulk volume change (it usually does not after the shrinkage limit is reached).

Final Answer:

No volume change