What is indicated by the symbol 'MH' in soil classification?

• A. Clay with low plasticity
• B. Plastic silts
• C. Liquid limit below 50
• D. Organic silt-clay of low plasticity

Answer: (B)

The symbol 'MH' in soil classification refers to plastic silts, specifically those that exhibit high plasticity characteristics. This classification is part of the Unified Soil Classification System (USCS), which categorizes soils based on their physical and engineering properties.

Plastic silts, designated as 'MH,' generally have a significant amount of silt-sized particles and can retain moisture, exhibiting plastic behavior when wet. This distinction is important for engineers and geotechnical professionals, as the presence of plasticity in a soil can significantly influence its behavior under load, its compaction characteristics, and its interaction with water. Understanding these properties is crucial for effective soil management and construction practices, as it helps predict how the soil will perform over time and under varying conditions.