Er. Vicky Singh, Er. Ajay Kumar Duggal
The increasing demand for sustainable pavement materials has encouraged the utilization of industrial waste in asphalt mixtures to improve pavement performance while reducing environmental impacts. This study investigates the combined use of Medium Marble Dust (MMD) and Very Fine Marble Dust (VFMD) in Bituminous Concrete (BC) Grade-2 prepared with VG-40 bitumen. The influence of marble dust on the mechanical and volumetric properties of bituminous mixes was ascertained by Marshall method and optimum replacement percentages were determined. Initially, the physical properties of aggregates, VG-40 bitumen, MMD, and VFMD were evaluated in accordance with relevant BIS codes and IRC/MORTH specifications. The Optimum Bitumen Content (OBC) for control mix by Marshall Mix Design method was determined as 5.51%. Medium Marble Dust was then used as a partial replacement for stone dust at replacement levels of 3%, 6%, 9%, and 12%, while 1% Very Fine Marble Dust with 1% cement was incorporated as a modified mineral filler. The prepared specimens were evaluated through Marshall Stability, Flow Value, Bulk Density, Air Voids (Va), Voids in Mineral Aggregate (VMA), Voids Filled with Bitumen (VFB), Marshall Quotient (MQ), and Indirect Tensile Strength (ITS) tests. The results indicated that the incorporation of marble dust improved Marshall Stability, Indirect Tensile Strength, Particle Packing, and Volumetric Characteristics while reducing Air Voids and the consumption of conventional Stone Dust. The Modified mixtures also exhibited improved crack resistance and overall pavement performance. The study concludes that the combined use of MMD and VFMD is a Technically Feasible, Economical, and Environmentally Sustainable Alternative for producing urable BC Grade-2 mixtures, promoting the beneficial utilization of marble industry waste in flexible pavement construction