ANALYTICAL INVESTIGATION ON PREDICTION OF FATIGUE CRACK GROWTH LIVES OF CRACKED NONHOMOGENEOUS MATERIALS

Abstract

Determination of the resistance of modern structural materials containing cracks to possible fatigue damages is important in evaluating the structures in terms of design and performance and to ensure a safe operation of the materials with cracks. Structures with damage/crack tolerance can be designed by prediction of crack growth lives of materials accurately and precisely. In this study, analytical investigations are performed to study the role of equivalent stress intensity factor range (Delta K-eq) equation in the modified Paris' law on prediction of the crack growth lives of cracked nonhomogeneous materials. The fatigue damage models are examined using the numerical and experimental data from literature reported for inclined cracked steel plates strengthened with carbon fiber reinforced polymer (CFRP) patch and two-phase composite material with slant interface. Results show that the Delta K-eq model plays a remarkable role on prediction of the crack growth lives.