Mechanical behavior of composite slabs with recycled concrete aggregates: A preliminary study

The imperative to mitigate the environmental footprint of concrete structures is increasingly recognized in scientific and engineering spheres. Of particular concern is the escalating demand for natural aggregates, which prompts the establishment of new quarries, thereby exacerbating environmental concerns. A viable remedy to this challenge lies in the utilization of recycled aggregates sourced from construction and demolition waste in concrete production. Concurrently, composite slabs offer a host of advantages over conventional reinforced concrete counterparts. These benefits encompass heightened strength and stiffness, expedited and simplified installation processes, and diminished environmental repercussions. Consequently, the incorporation of recycled aggregates in composite slabs emerges as a promising strategy for environmental sustainability within the realm of concrete construction. This experimental study investigates the mechanical behavior of composite slabs incorporating Recycled Concrete Aggregates (RCA). Twelve slabs were tested, employing three different span lengths, currently used in practice, (2.4 m, 2.8 m, and 3.2 m) and four mix designs with varying RCA replacement percentages (0 %, 30 %, 50 %, and 100 %). The slabs were subjected to four-point bending tests to determine their load-bearing capacity and interface bond strength. The presence of RCA seems to enhance longitudinal shear strength, which confirms its suitability in sustainable construction suggesting that it is actually right to follow the path herein outlined.