Design of Bituminous Concrete mix Gr-2 with R...

Design of Bituminous Concrete mix Gr-2 with Reclaimed Asphalt Pavement materials and Phosphogypsum as filler

Author Name : Ramanjaneyulu komarasetty, B. Ramesh

ABSTRACT

RAP collected from a number of old pavement sources, quality might vary. Interestingly, independent lab investigations found that normal RAP has roughly 4-6 percent of asphalt composition. The use of industrial by products as building materials may aid in the industry's sustainability. Phosphogypsum (PG) is a by-product of the phosphoric acid production process that is generated in large quantities, particularly in the fertilizer industries, and is often utilized as a supplemental fertilizer for soil treatment. To manage the hydration reaction rate of cement, PG might be used as a replacement for natural gypsum in the manufacturing of Portland cement. A proper design of bituminous mix is intended to result in a mix which is appropriately robust, durable and resistant to fatigue and permanent deformation and at the same time environment friendly and inexpensive. For a particular aggregate gradation, the optimal filler content by different materials as (Lime, cement, Stone dust) content is determined by meeting a number of mix design factors. In present study deals with the Effective usage of PG and RAP materials in BC mix. PG is used as Filler and RAP in BC mix. In flexible pavements bottom layers of bitumen are under tensile stress and strain owing to traffic loads. Indirect Tensile Strength (ITS) offers the concept about the cracking resistance of the mix. Better tensile strength leads to higher cracking resistance. By conducting Marshal stability test and ITS test, we identified that 25% of RAP Materials and 3% of PG giving good strength properties at 5.8% of Bitumen content.

Keywords: Reclaimed asphalt, Phosphogypsum, Bituminous concrete, Marshal stability.