The Principle of Virtual Work

Abstract

The methods of structural analysis presented in the previous chapters have been based on relationships between internal actions and displacements of the elements of a structure, and on relationships between the external loads and the internal actions. The relationships have been based on two fundamental requirements in the analysis of static structural systems: firstly that the structure must be in equilibrium, and secondly that the deformation of the structure must be compatible and meet the boundary conditions. Equilibrium has been satisfied by applying the equations of statics, while compatibility has been based on the geometry of the elastic curve or the geometry of the deformed element. The resulting techniques have been general enough to cover a wide range of structural analysis problems for both statically determinate and statically indeterminate systems.