Supistusvoima

Supistusvoima is a physical quantity describing the axial force that tends to compress, shorten, or squeeze a body along the direction of the force. In engineering and mechanics, it denotes the compressive loading that a member experiences when subjected to external forces. The term is often used in Finnish technical literature and is commonly paired with venytysvoima (tensile force), which describes axial pulling rather than pushing.

When a force F acts on a component with cross-sectional area A, the resulting compressive stress is F divided by A (sigma = F/A). This stress is measured in pascals (Pa) and its magnitude, relative to the material’s capacity, determines whether the member will deform permanently, buckle, or fail. Materials have a compressive strength (puristuslujuus), the maximum compressive stress they can withstand before failure, and design practice seeks to keep service-level compressive stresses well below this limit using safety factors.

Applications of supistusvoima are widespread in structural and mechanical engineering. Columns, foundations, and other axial members are designed to carry imposed compressive loads, with attention to stability under buckling for slender elements. In components such as plates and cores, compressive loads interact with material properties, geometry, and boundary conditions to influence overall performance.

Measurement of supistusvoima is typically performed with compression tests in which a specimen is loaded axially in a universal testing machine until yield or failure. The results, including ultimate compressive strength and modulus of elasticity under compression, inform material selection and structural design across industries.