One Million Red Ribbons

If in a structural analysis a structure material satisfy Hooke’s law, i.e. its behavior is linear, and we cannot disregard the effects of second-order (assume small deformations), then we would be facing a case of linear calculation, where all movements vary proportionally to the applied forces. The superposition principle says that displacement due to multiple loads acting simultaneously is equal to the sum of the displacements due to the action of each charge separately. The principle of superposition is applicable only in the case of linear calculation. The linearity allows that we can apply the superposition principle both stresses and deformations, internal forces and displacements due to different actions acting separately. The principle of superposition is not applicable if the material behavior is nonlinear, or if the structure (although the material obeys Hooke’s law) does not behave linearly due to geometry changes caused by the applied loads. It should be recalled that the structural analysis is to verify the resistance of a structure in the action of external loads.The superposition principle is useful in determining the most unfavorable of each bar condition since the interaction between different parts of the structure makes it difficult to know the exact load that produces the critical condition in the calculation. My blog: engineer of roads original author and source of the article.