applied fracture mechanics

Interacting Cracks Analysis Using Finite Element Method 375values. In strong interaction region 0 b/ a 1.0 , the values of KI , in,Dincreased rapidly forhigher crack-to-width ratio a/ W 0.5,0.45 and before grew slowly as the value of a/Wdecreases to a/ W 0.25 . Meanwhile, the values of KII , in,Ddeclined significantly at highercrack-to-width ratio a/ W 0.5,0.45 and before decreased slightly as the value of a/Wdecreases to a/ W 0.25 . For both crack interaction phase, the value of KI , in,Dis alwaysmuch higher than KII , in,D. In weak interaction region 1.5 b/ a 3.0 , it can be seen that thevalues of KI , in,Dincreased slightly before growing slowly and then maintaining at the samelevel to steady state at b/ a 3.0 . At the same region, the value of KII , in,Ddeclinedmoderately before decreased slightly and remain stable at the level of b/ a 3.0 . It meansthat mode II SIF is less influenced by damage shielding effect than mode I SIF. It alsodefined that the crack opening is more affected by damage shielding effect than the cracksliding. This has been clearly indicated in Fig. 7 (a)-(f) and Fig. 8(a)-(d).Figure 8. Variation of KI, in,D and KII , in,D for ( a/ W 0.05 0.2)