Utilization of alternative aggregates for roller compacted concrete pavements – A state-of-the-art review

In the last few decades, much attention has been given to Roller-Compacted Concrete Pavement (RCCP) technology for highway applications due to its numerous advantages over other conventional paving materials; lower life-cycle cost, lesser shrinkage, early opening to traffic, and reduction in the urban heat island are the main benefits associated with RCCP. Efforts have been made in the recent past by researchers to inculcate sustainable practices in RCCP by incorporating alternative materials. The present study is a state-of-the-art review of the studies published between 1997 and 2021 on the use of alternative materials for RCCP. The alternative aggregates that have been considered are recycled concrete aggregates, reclaimed asphalt pavement aggregates, crumb rubber, and electric-arc furnace steel slag aggregates. The potential of these alternative aggregates for RCCP has been critically assessed based on the fresh (optimum moisture content, maximum dry density, vebe time), mechanical (compressive strength, flexural strength, split tensile strength, abrasion resistance, modulus of elasticity), and durability properties (porosity, water absorption, freeze–thaw, and alkali-silica reaction). Consequently, the fundamental parameters of these materials affecting the behavior of RCCP and the ways to address them are summarized. Based on the extensive survey, the optimum proportion of these alternative aggregates for the production of sustainable RCCP have been identified and reported. Various gaps that need to be bridged through scientific as well as field understandings are also highlighted in this paper, along with outlining the possible future research scopes.