An overdeterministic approach for measuringK I using strain gages

An overdeterministic method for determining the opening-mode stress-intensity factor,K _I , from many measurements of the radial strain,∈ _rr , is described. The method was verified with an experimental study of a compact-tension specimen where strains along the 0, 45 and 90-degree lines were measured using strip gages with ten strain sensors per strip gage. The results indicated errors in the range of one to three percent with three or four parameter models of the strain field in the region near the crack tip. Paper was presented at the 1986 SEM Spring Conference on Experimental Mechanics which was held in New Orleans, LA on June 8–13.