STRENGTH CHARACTERISTICS OF SULPHUR-IMPREGNATED BITUMINOUS MIXES

Abstract

The immense demand and depleting sources of bitumen give us an ominous warning regarding its future cost and ready availability. The traffic on the road has increased manifold with regard to axle load as well as number of commercial vehicles. The high traffic intensity in terms of commercial vehicles, serious overloading of trucks and significant variations in daily and seasonal temperatures of the pavement have been responsible for early development of distress symptoms like ravelling, undulations, rutting, cracking, bleeding and shoving of bituminous surfacing. In an attempt to satisfy these pavement demands, work in the present dissertation has been done on bituminous wearing course. Sulphur has long been identified to have a beneficial effect on bituminous mixes and so bituminous mixes have been impregnated with sulphur to improve their various characteristics In the present study various tests have been conducted on sulphur-blended binders and sulphur-impregnated bituminous concrete mixes. The tests conducted on sulphur-blended binders are penetration test, softening point test, ductility test, viscosity test,. flash and fire point test, specific gravity test and stripping value test. The sulphur-impregnated bituminous concrete mixes were subjected to the tests like. Marshall stability test, Marshall Immersion test, iv uniaxial compression test, triaxial compression test, indirect tensile test and portable skid resistance test. The investigation proved that sulphur is a very suitable material for, both, modification of bitu-men as well as its extension. The sulphur/bitumen concrete mixes have been found to give better strength properties, reduced sensitivity to temperature variations, good durability, strong adhesion with aggregates and improved skid resistance characteristics. There is no environmental problem if temperatures of mixing and laying are well controlled. The economic analysis, done on various sulphur/bitumen concrete mixes, has proved that the use of sulphur in bituminous concrete is economically well justified.