Laboratory Investigations of Bituminous Concrete Grade 1 with Saw Dust Ash and Hydrated Lime in Replacement of Stone Dust as Fillers

Abstract

Hot Mix Asphalt pavements ( HMA ) are one of the fastest growing pavements in all over the world which requires the proper selection of the aggregates and the bitumen ( binder ) for its preparation . The type of aggregates used in the its preparation are coarse aggregates , fine aggregates and fillers as fines . Fillers play a significant role in the stiffness of the HMA mixes as they fill up the voids in the mixtures due to which stiffness of the mixes changes .There are large number of fillers like stone dust , lime , saw dust ash , glass powder etc . which can be used in the preparation of mixes but proper selection of fillers is needed which will be helpful in enhancing the properties of the HMA mixes . This present study deals with use of Saw Dust Ash with 1 % Hydrated Lime ( by weight of mix ) as a filler replacement of Stone Dust used in the preparation of the conventional mixes . Optimum binder content was obtained as 5.37 % by weight of aggregates by the help of stone dust ( conventional ) fillers and this obtained optimum binder content was then used same in all the modified mixes with saw dust ash and hydrated lime fillers . The modified specimens were prepared by replacing stone dust with saw dust ash 10 % , 20% , 30 % , 40 % , 50 % , 60 % , 70 % and 80 % and 1 % hydrated lime ( by weight of aggregates ) .Marshall tests , Static modulus tests , Indirect tensile strength tests were performed to study out results and make comparisons between the values . Resilient modulus was also found out by empirical relations so as to design the pavements using IIT pave software . The results concluded that Marshall stability , Resilient modulus , Static Modulus and Indirect tensile Strength were increased in 64.08 % , 39.72 % , 45.83 % and 33.33 % respectively correspond to usage of fillers at 60 % of Saw Dust ash and 1 % Hydrated Lime by weight of aggregates and with respect to conventional filler ( Stone dust ) in the HMA mixes . The optimum value of with 60 % of Saw Dust ash and 1 % Hydrated Lime by weight of aggregates is suggested as the optimum value which can be used in the design of flexible pavements .