Abstract
An analysis is given for the response of an impact loaded beam with a contact stiffness at the load point. The full frequency range is calculated and this is used to calculate the correction factors for the stress intensity factor and for the energy release rate as functions of loading time. These depend on the ratio of the contact to beam stiffness, α, and both experimental and analytical schemes for finding α are described. The procedures for finding α are explored for one set of data on an epoxy resin in the speed range 0.2–28 ms−1. Good agreement is found for these various methods. K d shows a substantial increase at high speed while G d varies only slightly. The analysis scheme seems to work well overall.
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Williams, J., Tropsa, V., MacGillivray, H. et al. Dynamic correction factors for K and G in high rate, SENB, impact tests. International Journal of Fracture 107, 259–278 (2001). https://doi.org/10.1023/A:1007607203882
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DOI: https://doi.org/10.1023/A:1007607203882