Abstract
Introduction. The article is about an assessment of the impact of impurities contained in the local construction materials on the mechanical characteristics of the concrete used in reinforced concrete structures in Burundi.
Materials and methods. The methodology of the study consisted in varying the quantity of impurities for the manufacturing of the concrete experimental cubic samples. The grain sizes of the studied ordinary concrete were in the favourable zones according to the recommended granulometry for standard concretes. Simulation of impurities was made by adding in the mixing water solid particles taken from a local rock called “red earth”. The particles were composed by (24 %) of clays, (38 %) of silts and (38 %) of sands. As for the used cement in this study, it was the type CEM I (32.5). The quantities of impurities were expressed in grams per litre of mixing water (g/l) and were varying from (0 g/l) to (100 g/l) with a step of (20 g/l). The prepared experimental concrete samples were stored in the laboratory of materials at the University of Burundi and were subjected to compression testing under hydraulic press after 28 days.
Results. The impact of impurities consisting of (24 %) of clays, (38 %) of silts and (38 %) of sands is identified. Each increase of (20 g) of impurities in a litre of mixing water induces an average decrease of (4 %) on the compressive strength and the Young’s modulus for an ordinary concrete.
Conclusions. The impact of impurities contained in the local construction materials used in the manufacturing of the concrete for reinforced concrete structures in Burundi is studied. Each increase of (20 g) of impurities in a litre of mixing water induces an average decrease of (4 %) on the compressive strength and the Young’s modulus of an ordinary concrete. For Burundi, a curve for the approximation of the bearing capacity of the concrete used in reinforced concrete structures according to the quantity of impurities contained in the local construction materials was established. Hence, it is advisable to start by the specification of the quantity of impurities contained in the construction materials before making the concrete for reinforced concrete structures in order to predict the mechanical performances of the concrete used in reinforced concrete structures.
Publisher
Moscow State University of Civil Engineering
Cited by
5 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献