Rheological behavior of high modulus asphalt binder and its indication for fracture performances

High modulus asphalt concrete (HMAC) has been used as a high-quality road construction material to tackle permanent deformation of asphalt mixtures primarily due to its exceedingly high modulus. However, rheological behavior, especially non-linear rheological behavior, and fracture behavior of high modulus asphalt binder (HMAB) are not well studied yet. In this study, linear and non-linear rheological tests, and fracture energy density tests were conducted on three HMABs, one base asphalt binder and one styrene-butadienestyrene (SBS) modified asphalt binder. The results show that HMABs have significantly higher rutting resistance, even after experiencing non-linear viscoelastic deformation. However, low cracking resistance was observed for HMAB due to its low ductility and low stress dissipation at its crack tip. Therefore, cracking resistance of HMACs should be a concern if they're subjected to tensile loading in application.

Automated summary

The study demonstrates that, while high modulus asphalt concrete (HMAC) has significantly higher rutting resistance, its low cracking resistance due to low ductility and stress dissipation at the crack tip should be a concern when subjected to tensile loading in application.