Performance Evaluation of Bituminous Mixes with Modified Binders using Roller Compactor cum Rut Analyzer (RCRA)

Abstract

Abstract: In India majority of roads are being constructed by flexible pavements. But the performance of the pavement largely depends on quality and type of materials used, construction methodology adopted, temperature, climatic conditions etc. Because of these variations in these parameters, pavements undergo distress/ failure. The different types of failure in flexible pavement are Rutting, Shovelling, Edge breaks, Cracks, Slippage etc. Rutting is a common phenomenon which occurs in flexible pavement surface due to overloading of vehicles and repeated application of wheel load. Rutting is defined as channelized depression in the pavement surface along wheel path due to heavy repetitive traffic load. Design of bituminous paving mixes greatly effects the performance of pavements. In the present laboratory research work, conventional bitumen is used in wearing/ surface course and Modified Bitumen is used in binder course of the layer. Pavement layers are constructed/casted in an Indigenously designed, developed and fabricated equipment called Roller Compactor cum Rut Analyzer (RCRA) and Rutting test is performed. The Rutting test is carried out on wearing course of bituminous layer (BC Gr-II with VG-30) and by adopting Binder course layer namely DBM Gr-II prepared with two different types of binders namely VG-30, SBS-70. The overall objective is to compare the Marshall properties of the conventional and Modified Bituminous mix and to study the rutting performance of these bituminous mixes.. Results shows that bituminous mixes prepared with Modified Bitumen/Binders (SBS-70) has a very high Marshall Strength and offers greater resistance to rutting. Keywords: Modified Bitumen, Bituminous Concrete (BC), Dense Bituminous Macadam (DBM) , Marshall Stability, Roller Compactor cum Rut Analyzer (RCRA), Styrene-Butadiene-Styrene (SBS).