Equilibrium and Reactions

Abstract

Statics of structures deals with structures that are exposed to loads and develop reactions and internal forces that leave the structure stationary. The present book deals with buildings and civil engineering structures that are supported to prevent motion, as opposed to space structures, trains etc. where motion is an integral part of the behavior. A fundamental tool of statics is the concept of equilibrium. In order to remain stationary the total effect of the loads and the reactions provided by the supports must be in equilibrium. This applies to the full structure and also to its different parts. In this chapter the equilibrium conditions for the full structure are used to identify requirements for the supports and to determine the reactions provided by the supports. The concept of equilibrium is developed further in the following chapters to deal with hypothetical parts of the structure, and thereby obtain knowledge of the distribution of the forces inside the structure.