ABSTRACT
Normally, before a structure is built, it is usually convenient and cheaper to design the structure using the theory of structural analysis. For large or unusual structures an additional safeguard of the structure is to determine the stresses in the structure to ensure that it will be safe. This chapter explains a number of different methods in experimental strain analysis, in particular those in electrical resistance strain gauges and photoelasticity. It shows to: understand the principle of operation of the Wheatstone bridge, understand some methods of water-proofing, understand Moire fringes, brittle lacquer techniques, appreciate semi-conductor and acoustical strain gauges. The chapter also shows to: understand foil gauge and foil gauge type of electrical resistance strain gauge, including advantages and disadvantages and gauge materials, appreciate different types of gauge adhesives, including cellulose acetates, epoxy resins, cyanoacrylates and Norton-Rockide. It then shows to: understand combined bending and axial strains.
