Rheological performance and NMR structure investigation of ultrasound crumb rubber modified bitumen

摘要

Rutting and fatigue cracking are the major distresses for road pavement performances. In addition approximately 9 to 10 kg of rubber from tyres per inhabitant and year are currently discarded in the industrialized societies . Thus, the introduction of crumb rubber (CR) in the production of asphalt rubber (AR) mixes for road pavements should be considered as a sustainable technology to transform an unwanted residue into a new bituminous mixture highly resistant to fatigue and fracture. As an asphalt additive, the wasted rubber needs to be devulcanized (UCRM). In this work base bitumens interacted with neat crumb and ultrasound devulcanized crumb rubber to produce AR mixes. By means of nuclear magnetic resonance and Rheology dynamic experiments we investigated the influence of ultrasound treated crumb rubber modifier on the morpho-structure and rheological properties of bitumen binder. Ultrasounds cause the partial devulcanization of the CR resulting into enhanced mechanical properties in a wide range of temperatures.