PSI - Issue 28

N. Kazarinov et al./ Structural Integrity Procedia 00 (2020) 000–000

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Nikita Kazarinov et al. / Procedia Structural Integrity 28 (2020) 2168–2173

2172

Fig. 3. Dependence of the breaking pulse amplitude on fracture time: Modelling and experimental results from Ravi-Chandar and Knauss (1984)

All the used material data and parameters of the oscillator are listed in table 1.

Table 1. Material properties and the oscillator model parameters Parameter name and units

Young’s modulus, (Pa) Poisson’s ratio, Shera modulus, , (Pa) Density, , kg/m 3 Longitudinal wave velocity, ! , (m/s) Shear wave velocity, " , (m/s) Rayleigh wave velocity, # , (m/s) Ultimate stress intensity factor, $% (MPa √ ) Zone size, , m Oscillator mass, & kg Oscillator stiffness, & N/m Oscillator critical deformation, % , m

Value

3900e6

0.35

1444e6

1230 2057 1176 1081 0.48

0.0048 0.2833

1.844442561e9 0.1194029e-4

4. Conclusion

A relatively simple mass-spring model (linear oscillator) was considered in the work. Failure of the system according to critical spring stretch fracture condition was studied. Two types of dynamic loads were investigated: rectangular pulse load and linearly rising load. In the first case it was shown that the effect of fracture delay can be observed for certain combinations of the loading pulse