A compressive strength model for roller-compacted concrete with fly ash

摘要

Roller-compacted concrete (RCC) is typically used in the construction of dams and road pavements since it provides substantial benefits over conventional concrete for the construction of such structures such as faster construction, lower costs of construction and materials, etc. Incorporating fly ash into RCC can further reduce cost of materials and enhance the concrete performances. Recently, a huge fly ash RCC dam (Tha Dan Dam) project was started in Thailand. This utilises the largest the volume of RCC in the world at 5 million m~3. However, one of the main problems concerns the mix proportion of RCC with fly ash. This paper presents a model for predicting compressive strength of RCC with fly ash in order to minimise the process of trial mixing. The model was formulated based on quantities of concrete ingredients, chemical compositions and physical properties of cement and fly ash. It was found that at room temperature of 28 +- 3℃ the proposed model could be used to predict compressive strength of the tested mixtures of roller-compacted concrete with fly ash designed for dams and road pavements at the ages between 3 and 91 days with satisfactory accuracy.