Mixture Optimization of Concrete Paving Blocks Containing Waste Silt

Abstract

Most of the waste materials recycled for the production of new construction materials are by-products of various manufacturing processes, such as the aggregate washing process. Recycling such materials is of paramount importance since it could reduce the adverse environmental impacts resulting from landfilling. Various studies have attempted to recycle different types of waste materials and by-products into concrete paving blocks. However, the availability of literature on concrete paving blocks containing waste silt is quite scarce. Thus, the current paper focuses on mix design optimization and production of concrete paving blocks containing high amounts of waste silt resulting from the aggregate production process. Using the mixture Design of Experiments (DOE), 12 sets of concrete paving blocks with different aggregate blends were produced to optimize the mix design. Once the final mix design was achieved, the physical and mechanical properties of the concrete paving blocks were investigated following the EN 1338 standard. Shape and dimension measurements and various tests, including water absorption, tensile splitting strength, abrasion resistance, and slip/skid resistance were conducted on the experimental concrete paving samples. Overall, the produced concrete paving blocks showed promising properties for future applications in pedestrian walking paths.