DEVICES FOR THE EXPERIMENTAL-DETERMINATION OF INDIVIDUAL STRESSES FROM THERMOELASTIC DATA

Three forms of bonded 'gauge' are described which can be used for the determination of separate stresses on the surface of a stressed body f rom thermoelastic data only, without recourse to supplementary experim ental or computational techniques. The dimensions of the gauge, the ga uge material and the form of bonding between the gauge and the stresse d body are such that the thermoelastic signal from the gauge, in conju nction with that from the adjacent surface of the stressed body, allow s the determination of the surface stresses in the stressed body in tw o orthogonal directions (e.g. parallel and normal to the 'length' dire ction of the gauge). The use of these gauges for the determination of the magnitudes and directions of the principal strains and stresses on the surface of the stressed body is also described.