What is the maximum LL value for stabilizing material?

• A. The maximum LL applicable is 45
• B. The maximum LL applicable is 35
• C. The maximum LL applicable is 40
• D. The maximum LL applicable is 50

Answer: (C)

The key idea here is how plastic the soil is, as measured by the liquid limit (LL). LL tells you the water content at which a soil loses its plastic behavior and becomes liquid. Soils with higher LL are more clayey and plastic, which makes stabilization with common binders harder to achieve reliably.

For stabilizing material in typical practice, soils with LL up to about 40 respond well to standard stabilization methods, giving workable moisture ranges, good compaction, and durable improvements. When LL is higher than 40, the material is too plastic and prone to swelling and moisture sensitivity, making reliable stabilization more difficult and often requiring more complex or expensive approaches.

That’s why 40 is the maximum LL value for stabilizing material in this context. The other numbers either exceed that practical limit or are simply not the upper bound being asked for.