Use of Concrete Wastes in Concrete Paving Blocks by Thermal-Mechanical Separation
A concrete paving blocks was produced using pretreated concrete wastes as main raw material by pressure forming and steam-curing at 70°C. The test results showed that with the increase of water addition, the paving blocks increase its strength. And as the additions of water amount reach to a critical value, the compressive strength has an adverse change and decreased. As the rise of ratio of cement and wastes, the compressive strength also increases. The difference in various ratios of cement and wastes is that the difference of water needed as the compressive strength achieved its highest value. The thermal treatment temperatures has greatly influence on the compressive strength. The increments of thermal-treated temperatures induce the active material to form and cause the particle grading more reasonable in the concrete wastes, which is benefit to the shaping of specimen and increasing of strength. The maximum compressive strength of 53.2 MPa is obtained in the mixture thermal-treated at 800°C by adjusting the water additions.
Hui Li, Yan Feng Liu, Ming Guo, Rui Zhang and Jing Du
Q. B. Tian et al., "Use of Concrete Wastes in Concrete Paving Blocks by Thermal-Mechanical Separation", Advanced Materials Research, Vols. 374-377, pp. 1303-1306, 2012