Issue 48

V. M. G. Gomes et alii, Frattura ed Integrità Strutturale, 48 (2019) 304-317; DOI: 10.3221/IGF-ESIS.48.30 315 failure. However, if the edge distance, e 2 , is lower than the end distance, e 1 , the failure occurs mainly on the net cross- section, or if the edge distance is greater, the failure occurs by shear. Tab. 7 shows the ratios obtained from geometry data of specimens, verifying an average of e 1 / D hole and e 2 sup / D hole of 1.93 and 2.22, respectively. For these ratios, specimens made of S355MC steel grade showed failure by shear and the S350GD exhibited failure by splitting and shear (Fig. 8 A and B above) even for a ratio e 1 / D hole lower than 2.5, so it is possible that for e 1 / D hole values of 1.93 would be very close to the lower bound of the bearing resistance. As regards to multiple bolted connections, the failure occurs on net cross- section for e 2 inf / D hole equal to e 2 sup / D hole and lower than 2.5, p 2 / D hole equal to 2.80 and p 1 / D hole equal to 2.79. Taking into consideration that the crack began between two holes it is possible that the ratio p 2 / D hole will be very important for this type of failure. Figure 7 : Experimental vs. numerical load-displacement curves for specimens made of S350GD and with zinc coating plus painting; preload level applied 70% Fu or 560 MPa. Figure 8 : Experimental vs. numerical (equivalent plastic strain fields at ultimate loads) failure modes: above, 1+1 bolted joints; below, 4+4 bolted joints (A-S355MC, B- S350GD).