Structural Madness

A course in structural engineering starts from a particular type of structural analysis called determinate structural analysis. Here you study anything regarding determinate structures, whether it may be a simply supported beam, a 3 hinged arch, a truss. Everything is determinate and that means number of unknowns is equal to the number of equations. That is great, you see the unknowns, form the equations and figure out the value of the unknowns. As simple as that. But this isn't everything about structural engineering. When you design a building or a bridge, there is more to it than just a determinate structure.  Let us take a simply supported beam and a fixed ended beam.In case of a simply supported beam, you apply the load and the amount of the load carried by the beam is equal to the strain energy stored in the beam. Let us assume a beam with a load capacity of 100 kN. When you load the beam, then it will be deflected by a certain amount (x). So the work done by the load