Effect of Typha Australis Aggregate on the Mechanical Strength of Concrete

Abstract: As part of this work, different dosages of Typha Australis aggregate, mixed with fine sand from the Chari River in the city of N'Djamena and cement, were used to formulate samples of Typha concrete that we characterized with a view to its use in construction. With this in mind, we carried out a particle size analysis of the sand. This allowed us to notice that the soil is purely sandy and has good characteristics for manufacturing concrete. The proportions of Typha used fluctuate between 0.5% and 5% in steps of 0.5. On the other hand, we produced sixty-six (66) prismatic samples (one for each scenario), measuring 4x4x16 cm, with Typha percentages ranging from 0.5% to 5% in increments of 0.5%, and control samples with no Typha additives for each scenario. We carried out two analysis scenarios. In the first scenario, S1, the ratio of cement to sand is 1/4, while in the second scenario, S2, the ratio of cement to sand is 1/3. The study focuses on the curing processes after 7 and 28 days. The results obtained showed that the Typha concrete studied possesses the required mechanical characteristics, making it a practical material for use in partitions and low-load-bearing structures with low heights. However, increasing the proportion of Typha decreases the mechanical characteristics, rendering the concrete less suitable for its intended purpose. The flexural test shows a strength of 1.05 MPa for the S1 series on the 7th day and 1.28 MPa for the S2 series on the 28th day. The compressive test indicates strength of 0.32 MPa for the S1 series on the 7th day and 0.33 MPa for the S2 series on the 28th day. The results indicate that incorporating Typha into the concrete develops a material suitable for use as wall infill.