Rubblized concrete refers to the process of breaking down existing concrete structures, typically pavements, into small, rubble-like pieces which are then used as a base for new pavement overlays. This method is often employed as an alternative to complete demolition and removal, providing a sustainable way to reuse materials on site. The mechanism involves using specialized machinery to fracture the existing concrete layer without disturbing the underlying base. The resulting rubblized layer provides a stable and workable foundation for new roadways or structures, effectively recycling the old material.