Study of The Influence of Storage Media on the Thermo-mechanical Behavior of Concrete and Cement Blocks

Abstract

Once all construction materials have been formulated, it is necessary to find a suitable environment in which to store them before using them in the building. Generally speaking, in developing countries, materials are not preserved under the real conditions of temperature and humidity and are exposed to often severe climatic conditions. This has an impact on the behaviour of these materials. With this in mind, we conducted our study on concrete and cement bricks, the two materials most commonly used in building construction in Africa. The overall objective of our study is to analyse the effect of storage environments, particularly ambient conditions of temperature and hygrometry, on the thermal and mechanical properties of concrete and cement bricks in a dry tropical climate. To achieve this objective, we first analysed the quality of the materials used to formulate the concrete and cinder block samples. Next, we chose a formulation method that would enable us to obtain the optimum proportions of aggregates. Finally, the thermal and mechanical parameters were measured using the KD2-Pro device and a mechanical press, respectively. The concrete and cinder block samples were stored for 28 days and 10 days respectively in the open air under ambient climatic conditions (35°C on average),in a water tank (29°C on average) and in a climatic chamber (20°C and 53% relative humidity). Results ranged from 1.126 (± 0.003) to 1.289 (± 0.023) W.m-1. K-1 for thermal conductivity. Mechanical test results ranged from 3.93 (±0.45) to 4.13 (±0.27) MPa for flexural strength and 16.42 (±0.17) to 17.95 (±0.21) MPa for compressive strength. The lowest thermal conductivity was obtained in the climatic chamber, with a value of 1.126(±0.0032)W.m-1.K-1.The best compressive strength of concrete and the best flexural strength of cement blocks were obtained for samples stored in the climatic chamber. For the best mechanical and thermal behaviour of these two materials, we recommend a temperature not exceeding 20°C as the storage environment in a dry tropical climate.