On the Shrimali and Lopez-Pamies theory on viscoelastic fracture mechanics

dear collegues

I have been attracted recently by a theory from Shrimali and Lopez-Pamies which is based on experimental evidence obtained from Suo's group in Harvard in 2012 in a (rather limited, unfortunately) set of experiments on rubber. The theory assumes that the stretch to nucleating a crack is constant and independent no stretch rate. The theory is then build on that, to predict the increase of fracture energy with rate.

However, limiting the case to the very standard case of linear materials, I obtain from the classical Schapery cohesive model that the stretch at nucleation is FAR from rate independent and can vary by a factor of 30-100 for typical rubbers! This seems also to agree well with some other experiments including some done here in Bari and some from Creton in Paris.... However, I have found that other predictions like in steady state tearing tests and peeling tests could be reasonable, so the matter is complicated.

Is anyone working on this area?

Regards, Prof. Michele Ciavarella

Comparison with Schaperyhttps://www.researchgate.net/publication/374144999

Trouser tests:https://www.researchgate.net/publication/374081443