This paper on "Experimental/Numerical Evaluation of Mixed Mode Stress Intensity Factors for a Crack on a Beam Structure" was presented at the 5th International Conference on Reliability of Finite Element Methods for Engineering Applications - 10-12 May 1995, Amsterdam, The Netherlands.

Abstract

This paper describes an experimental and a numerical method for separating the mixed-mode stress intensity factors of a crack on a full scale load bearing composite beam structure. For experimental investigation, the distributions of the first order stress invariant (σ₁ + σ₂) around a crack tip subjected to the first and second mode loading conditions are measured by means of a full field SPATE system (Stress Pattern Analysis by Thermal Emission). To verify SPATE measurements, strain gauging techniques are also used to confirm the sum of principal stresses measured at points of interest. Results obtained by SPATE are then validated by finite element (FE) models with the use of closed-form methods. Finally, the advantages and disadvantages of applying the SPATE technique to the problem are discussed.