Performance of chem-crete bitumen in hot climates

Abstract

When bituminous materials are subjected to high road temperatures and traffic stresses they deform and rut easily. Wide temperature ranges are encountered in the tropical countries and the current conventional binders have failed to provide satisfactory performance. Considerable research has been done on binder additives in an effort to improve the rheological properties of the current conventional binders. Few of these have so far been widely accepted. They are either too expensive for ordinary road construction jobs or require special handling equipments and techniques.

Chem-crete bitumen has recently been introduced into the market and is reported to function satisfactorily under high road temperatures and is capable of upgrading stability of deficient aggregates such that they can be used in road construction. A laboratory study on asphaltic concrete and sand asphalt mixes was carried out in order to investigate the effects Chem-crete had on stability, tensile strength, and temperature susceptibility of conventional mixes. The results obtained indicated that Chem-crete does improve stability, compressive and tensile strengths of conventional mixes, improves substantially stability of deficient aggregates but makes the conventional binder more temperature susceptible.