PHOTOELASTIC DETERMINATION OF STRESSES IN A SIMULATED FILLET WELDED T-JOINT

Abstract

Fi l let welded T-joint Sri t and , without cracks l ike discontinuities are analysed using photoetasti.city method. Stress intensity factors for opening mode are determined for undercut at zipper toe, under cut at Lower toe, centreline crack and intrinsic flaw under various loading conditions, weld dimensions and flange flexibilities. Load angle was varied between 00 and 900 using Loading frame, specially fabricated for present study in each case. Three different equal weld leg sizes considered are 5mm, Smm and 1e mm. The flange flexibility values varied between 100mm to 60mm in step of 10mm. Experimental details are presented to determine mode I and mode ii stress intensity factors' values through coordinate measurements of the maximum radius and corresponding toad angle 8 of epogee point on a tsochromatic fringe Loop. The measured m experimental data were analysed using smith's approach. The analysis of photoelastic fringe patterns show that the upper toe and tower toe regions are the highly stressed locations. Further it is concluded that the undercut type of defects at Lower and upper toe regions are more severe and prone to crack initiation sites as compared to centre Line crack or intrinsic flaw. The experimental results are given in terms of unit stress intensity factors vs Load angle discussed to show that of mode I stress intensity factor values are appreciably influenced by flange flexibility, weld leg size as well as applied Load angle.