Type A soil is characterized by what maximum unconfined compression strength?

Type A soil is defined by its unconfined compressive strength, which is a key indicator of its stability and load-bearing capacity. The classification of soils according to their engineering properties is vital in civil engineering and geotechnical engineering, especially when determining suitability for construction projects.

Type A soils, commonly classified as cohesive soils like clay, typically have an unconfined compressive strength of at least 1.5 tons per square foot. This level of strength signifies that the soil is relatively stable and can support significant loads without failure under unconfined conditions. This characteristic makes Type A soil suitable for various engineering applications, including foundation work and earth retaining structures.

The other options reflect lower compressive strength values that do not meet the criteria for Type A soil. Understanding this classification helps engineers assess the conditions of the soil on a construction site, ensuring the design and safety of structures that will be built above it.