Development of Artificial Stone through the Recycling of Construction and Demolition Waste in a Polymeric Matrix

Abstract

Civil construction is one of the oldest activities known to humanity, with reports indicating that builders from the Roman Empire were already seeking to reuse materials. Currently, considering the depletion of natural resource supplies, the recycling of solid construction and demolition waste (CDW) not only provides new products but also presents ecological and economical alternatives. In this context, this research explores new variables for the disposal of CDW, with the manufacturing of artificial finishing stones appearing as a strong possibility to be studied. This research presents the development of a new composite from CDW, using an orthophthalic polyester resin as a binder. The waste was sieved and separated by granulometry using the simplex centroid method. The best-compacted mixture was determined statistically by ANOVA and Tukey’s test. The waste was characterized by X-ray fluorescence, and the resin by Fourier transform infrared spectroscopy. Artificial stone slabs were produced with 85% waste and 15% resin by mass, using the vibro-compression and vacuum system. They were subsequently cut for mechanical, physical, and chemical tests. Microstructural analysis was performed using scanning electron microscopy on the surfaces of the fractured compositions, as well as on the grains. The artificial stone with the best results had a density of 2.256 g/cm3, a water absorption of 0.69%, and an apparent porosity of 1.55%. It also exhibited a flexural strength of 34.74 MPa and a compressive strength of 111.96 MPa, alongside good results in alterability and thermal tests. In this satisfactory scenario, the use of this waste in the composition of artificial stones is promising, as it directly aligns with the concept of sustainable development. It replaces the end-of-life concept of the linear economy with new circular flows of reuse, restoration, and renewal, in an integrated process of the circular economy. Additionally, the quality of the final product exhibits properties similar to those of commercially available artificial stones.