Physical & Geotechnical Characterization of Bambui & Garoua I River Sands for Sustainable Micro-Concrete Roofing Tiles

In Cameroon, many Micro-Concrete Roofing (MCR) tiles have been replaced with aluminum sheets due to leakages caused by poor-quality raw materials, such as river sands with high organic and clay content and sea sands with alkaline salt issues. Quarry sands have been considered as a substitute but are costly and require blending with other sands to meet production standards. This study investigated the use of river sands from Bambui and Garoua I in MCR tile production. Physical tests showed both sands had well-graded particles and acceptable sand equivalent values (>80%). MCR tiles were produced following standard procedures, and mechanical tests revealed favorable properties, including flexural strength, permeability, water absorption, and impact resistance. Comparative analysis showed Garoua I river sand-based tiles performed better than those from Bambui, with higher flexural strength (12.08 MPa vs. 10.68 MPa), lower water absorption (10.31% vs. 10.70%), and greater impact resistance (110mm vs. 900mm ball drop height).