See normal strain and shear strain . In a material, strength refers to a level of stress at which there is a significant change in the state of the material, e.g., yielding or rupture. In a structure, strength refers to a level of level of loading which produces a significant change in the state of the structure, e.g., inelastic deformations, buckling, or collapse. A system of forces which is statically equivalent to a stress distribution over an area. The intensity of internal force acting at a point in an object.
Stress is measured in units of force per area.
See shear stress and normal stress . An idealization for analysis purposes of a real or conceived structure. A structural model includes boundaries limiting the scope of the analysis. Supports occur at these boundaries, representing things which hold the structure in place. A support contributes to keeping a structure in place by restraining one or more degrees of freedom .