Influence of environmental temperatures on the concrete compressive strength: simulation of hot and cold weather conditions

This work has as objective to study the influence of mixing hour in the concrete properties such as workability and compressive strength in hot and cold weather conditions from an industrially applied point of view. The foremost studied variable was the concrete mixing hour, having used five mixing hours for every weather conditions. For each mixing hour, were carried out three concrete batches and 15 cylindrical concrete specimens were made for measuring compressive strength at 7 and 28 days. Besides, for each concrete batch the hydration kinetics was studied depending on the climatic situation and mixing hour. In the results regarding compressive strength, the best mechanical performances presented by the concrete correspond to the situation when the minimum difference between ambient temperature and concrete temperature exists; that is at later hours of the day for hot weather conditions.