unconfined compression strength
Technical term used in soil mechanics and material testing; refers to the compressive strength of a material under unconfined conditions.
Unconfined compression strength is used to evaluate the strength of cohesive soils.
圧縮強度 is a more general term for compressive strength, while 一軸圧縮強さ specifically refers to unconfined compression strength.
Compound of 一軸 (uniaxial) + 圧縮 (compression) + 強さ (strength).