Stresses and deformation in soils
This chapter covers total and effective stresses in a soil element and also a review of Continuum Mechanics. It presents a summary of continuum mechanics with emphasis on Soil Mechanics applications. Only the main concepts and important equations, but no formulae deduction, are presented. The ultimate purpose of this study is to find out the state of stress (and deformation) of any point in a soil mass. This implies that the normal and shear stresses (and deformation), relative to any plane that intercepts the chosen point, are known. It is seen, however, that provided we know the stresses relative to three orthogonal planes, the state of stress can be found out. In many practical applications a three dimensional problem can be simplified to two dimensions only. This can lead to an important simplification in the mathematical treatment of engineering problems. A frequent case, when dealing with stresses and deformations, is the plane strain case.