Analysis of Strain

Abstract

The forces that act on a solid (in our case elastic) body produce deformation of the body. In fluids they produce flow. One of the basic problems in continuum mechanics is to describe, quantitatively, the deformation that the body experiences. This is achieved by introduction of measures of deformations. Measures of deformation are based on geometrical quantities that describe deformation of the body. By assumption the body that we treat is a continuum. This implies that the changes in the body are continuous so that a small neighborhood of a given point in an undeformed state remains the neighborhood of the same point in the deformed state too. In other words, no finite (however small) part of the body could be deformed so that its volume becomes equal to zero.