A Micromechanics Based Constitutive Model For Brittle Failure at High Strain Rates

Harsha S. Bhat, Ares J. Rosakis, & Charles G. Sammis

Published April 2012, SCEC Contribution #1598

The micromechanical damage mechanics formulated by Ashby and Sammis [1] and generalized by Desh- pande and Evans [2] has been extended to allow for a more generalized stress state and to incorporate an experimentally motivated new crack growth (dam- age evolution) law that is valid over a wide range of loading rates. This law is sensitive to both the crack tip stress field and its time derivative. Incorporating this feature produces additional strain-rate sensitivity in the constitutive response. The model is also exper- imentally verified by predicting the failure strength of Dionysus-Pentelicon marble over strain rates ranging from ∼ 10−6 to 103 s−1. Model parameters determined from quasi-static experiments were used to predict the failure strength at higher loading rates. Agreement with experimental results was excellent.

Citation
Bhat, H. S., Rosakis, A. J., & Sammis, C. G. (2012). A Micromechanics Based Constitutive Model For Brittle Failure at High Strain Rates. Journal of Applied Mechanics, 79(3). doi: 10.1115/1.4005897.