Estudo das características do betão branco comparado ao betão cinzento e sua aplicação em projectos de engenharia

Abstract

This study presents an analysis of the behavior of white concrete, comparing it to gray concrete in terms of production and properties in both fresh and hardened states. Mixtures of strength classes C30/37 and C40/50 were analyzed for both white and gray concrete, with a focus on compressive strength development. The results indicated that white concrete exhibits an accelerated gain in compressive strength during the first seven days; however, this trend reverses between 7 and 28 days, when its strength development slows compared to gray concrete. Factors such as the water/cement ratio and the degree of compaction proved to be crucial for compressive strength, while the finer particle size of white cement contributed to higher water absorption, making it more difficult to achieve fluid consistency. Technical challenges related to the interaction between white cement and superplasticizers, variations in the color of white concrete, and thermal shrinkage cracking were identified, with specific recommendations proposed to mitigate these issues. The findings of this research establish technical parameters for optimizing the production and application of white concrete, highlighting its advantages and limitations while proposing practical measures to ensure both structural and aesthetic performance. The study also emphasizes the importance of specialized technical control throughout the entire production process.