Experimental and numerical investigation on fracture behavior of CTS specimen under I-II mixed mode loading

Numerical Simulation of Mixed‐Mode Fatigue Crack Growth for Compact Tension Shear Specimen

“…Furthermore, for mixed-mode loading in the CTS geometries with loading angle α � 30°, the cracks are propagated to some extent differing to the original crack front direction. For these three geometries, the mixed-mode crack propagation angles (a/W � 0.3, 0.5, and 0.7) are about 5.5°, 8.5°, and 8.5°, respectively, which are almost in agreement with experimental angles of [39]. For the above three loading angles situations (α � 90°, α � 0°, and α � 30°), regardless of the length of the initial crack for the same load angle (α), the angles of the crack growth in each case are close to each other.…”

“…e influence of the first mode (K I ) decreases as α increases and vice versa for mode II. e crack direction angles of three geometries with different initial length of cracks (a/W � 0.3, 0.5, and 0.7) are 6°, 10°, and 12°, respectively, which are identical to the experimental angles tested by [39]. Furthermore, for mixed-mode loading in the CTS geometries with loading angle α � 30°, the cracks are propagated to some extent differing to the original crack front direction.…”

“…In addition, the paths of crack growth of load angles 30°, 45°, 60°, and 75°were validated with comparison to practical crack paths tested by [36] as shown in Figure 10 with good agreement. e predicted crack growth path has been compared to the experimental test performed by [39] with different crack lengths (a/w � 0.3, 0.5, and 0.7) and different load angles 0, 30, 60, and 90 as shown in Table 3.…”

“…For pure loading of mode II (α � 0°), the direction of the crack growth is controlled by the second mode of SIF (K II ) [39].…”

“…Experimental test [39] and the cracks all grow with different angles based on equation (2) as the values of K II are higher, whereas for complete mode I loading (α � 90°), crack paths are dominated by the first mode K I and the crack is going to grow straight. e influence of the first mode (K I ) decreases as α increases and vice versa for mode II.…”