Physical Characterization of Ecological Briquettes Based on Vertisols and Sorghum Bicolor CS54 Fibers

The aim of this work is to perform the physical characterization of ecological briquettes based on vertisols and fibers of Sorghum bicolor CS54 from the city of Maroua located in the Far North of Cameroon, a country of Sub-Saharan Africa. Three sites of study have been identified and investigated, namely ZL (Zokok Laddeo), Ngassa (NG), and KG (Kongola). Different percentages of added plant fibers have been realized, including 0%; 2%; 6%; and 8% of fiber additions for each site considered. The experimental tests have revealed that the plasticity of clays is between 16.56% and 25.96%; it is higher in the Zokok Laddéo site (25.96%); and it is between 16.56 and 23.78% for Ngassa and Kongola. The main aggregates observed in the three sites are gravel, which varies between 1.90% and 16.12%, sand between 4.99 and 53.12%, silt, which varies between 2.30 and 36.10%, and clay which fluctuates between 20 and 38.77%. The coefficient of resistance to abrasion varies between 7.19% and 24.35 for the three sites. The highest rates are those of the samples from the Ngassa site (24.35%). The linear shrinkage of the samples varies between 2.9 and 13.04%. The apparent density of the briquettes are between 1587.30 kg/m3 and 2138.13 kg/m3; they are higher for the sites of Zokok Laddéo and Ngassa. The overall coefficient of the capillary rise value is between 0.42% and 16.85%. The interval variation in the obtained results for the different parameters are for most cases and depending on the sites studied in accordance with the defined international standards. These results have proven that the addition of bicolor Sorghum fibers CS54 in vertisols could improve the performance of constructions based on local and eco-friendly materials.