Since the Istradefylline release rate for the notched beam is related to dC/da :equation(14)GI=F22w×dCdaand KI for plane strain is related to GI :(15)KI=GI×E1−ν2
Combining Eqs. (13), (14), (16), (17) and (18), KI for the notched cantilever beam can be obtained:equation(16)KI=61−ν2FLwt1.521−a/t3+1−t/L1−a/t20.5
The numerical comparison of this equation with the semi-empirical Eq. (5) for different L/t ratio is shown in Fig. 4. It is clear that the newly derived analytical equation generates very similar KI value as the semi empirical equation. Also it is clear from Fig. 4, the ratio of L/t, (i.e., the loading distance relative to the beam thickness) does not have much influence on KI.
Fig. 4. Numerical comparison of newly derived analytical equation (Eq. (16)) with the semi empirical equation (Eq. (5)).Figure optionsDownload full-size imageDownload as PowerPoint slide
Based on evolutionary tree same LLBV assumption, similar solutions for 3-point and 4-point bending were also derived:equation(17)KI=381−ν2FLwt1.521−a/t3+1−t/L1−a/t20.5for 3-point bend andequation(18)KI=381−ν2FS1−S2wt1.53−a/t1−a/t1.50.5for 4-point bend.