Fig. 4.3 (a) Potential energy of a spring-mass system; (b) loss in potential energy due to change in position.

P in the deflected equilibrium state is given by

We now define the total potential energy (TPE) of a system in its deflected equilibrium state as the sum of its internal or strain energy and the potential energy of the applied external forces. Hence, for the single member-force configuration of Fig. 4.1(a)

For a general system consisting of loads P\,P2 ,P„ producing corresponding displacements (i.e. displacements in the directions of the loads: see Section 4.10) A!, At, ..., A„ the potential energy of all the loads is r=l r= 1

and the total potential energy of the system is given by n

0 0

Post a comment