Issue 22

R. K. Bhagat et alii, Frattura ed Integrità Strutturale, 22 (2012) 5-11; DOI: 10.3221/IGF-ESIS.22.01 9 Figure 8 : Comparison of stress intensity factor K I for load σ = 1.125N/mm 2 , biaxial load factor = 1 and a/W= 0.06. Effect of crack inclination angle on KI for two non-parallel cracks When there are two parallel and symmetric cracks in a plate then K I for lower K I ( L) and upper K I ( U) crack decreases with the increase of crack inclination angle as shown in Fig. 9. Figure 9 : Effect of crack inclination angle α on K I for two non parallel crack; a/W = 0.08, k = 0.75, S = 1.5 and B = 24. Effect of crack inclination angle on K I for two parallel cracks When there are two parallel cracks in a plate then K I for lower and upper crack decrease with the increase in crack inclination angle, whereas upper crack has slightly more value than the lower crack as shown in Fig. 10. Fig. 10 shows that for lower and higher crack inclination angle, K I for lower and upper crack are approximately same because cracks are tends to parallel to either major or minor load axis, and are close mode I or mode II condition and hence there is negligible variation in the K I for lower and upper crack. Effect of crack inclination angle α on two non-parallel cracks When there is two parallel and symmetric crack in a plate K II for lower K II ( L) and upper K II ( U) crack the value of K II are approximately same for both the crack as shown in Fig. 11 and it increases up to α = 450 and then it starts decreasing hence, maximum value is observed at α = 450. Effect of crack inclination angle α on two parallel cracks When there are two parallel cracks in a plate then K II increases with the increase of crack inclination angle for upper and lower crack up to 450 and then it starts decreasing as shown in Fig. 12. Hence, maximum value is obtained at α = 450.