PSI - Issue 28

1978 Yuri Petrov/ Structural Integrity Procedia 00 (2019) 000–000 In (3) and (4) = ( 0 , + ) , 1⃗( , ) = ( 0 ( , ), + ( , )) is the displacement vector, and are Lame coefficients and denotes mass density. Yuri Petrov et al. / Procedia Structural Integrity 28 (2020) 1975–1980 4

Fig. 1. Simulation scheme.

The stress intensity factor values are calculated using formulas for a moving crack deduced in works by Nakamura et al. (1985) and Shih et al. (1986). A special postprocessing external software was developed for ANSYS. 4. Results In this work experiments from works by Ravi-Chandar and Knauss (1984a,b,c) were numerically simulated. In these experiments cracks propagated in Homalite-100 specimens due to pulse load applied to the faces of the initial crack. The crack tip position was registered using high-speed camera and the SIF value was measured using method of caustics. Thus, SIF-crack velocity dependencies could be investigated.

The following material properties were used in course of the conducted simulations:

Table 1. The used Homalite-100 Material properties Material parameter

Young’s modulus ( ) Poisson’s ratio Density ( ! ⁄ ) Ultimate stress " ( )

value 3900 0.35 1230

48 Ultimate stress intensity factor #" ( √ ) 0.48 Incubation time ( ) 1 or 9

The 9 µ s incubation time value was evaluated analytically in work by Petrov and Morozov (1994). Figures 2b and 2c present numerically obtained SIF-crack velocity dependencies obtained for two incubation time values and