ABSTRACT
This chapter investigates the constraint reactions in an elastic system affected by displacements in the places of other removed constraints and by exertion of loads upon the system. It includes theoretical provisions, namely, the generalized superposition principle and Rayleigh theorems, being set out for a plane system of elastic bodies bound by connections of the first type. The chapter considers the states caused by displacement at any connection of the first type. The rigid compound nodes with one coherent connection are used, in particular, in the construction of influence lines for internal forces by the kinematic method. The reaction induced by unit displacement in the direction of the removed constraint is referred to as a unit reaction.
