Study on Carbonation Phenomenon Impact on RCC Pavements (RCCP) Technical Performance

Roller compacted concrete (RCC) nowadays is majorly used in two quite different fields. The first application of RCC is in the dam construction and the second is as the pavement. One of the most important parameters in the implementation of concrete structures is their durability, this is especially crucial for pavements which face with harsh enviroments and countinous dynamical loads. Regarding the using of RCC pavements in areas with various environmental conditions assesing the durability parameters of RCCP are very important. Carbonation is one of most important phenomones which affect the durability of concrete structures. The main purpose of this research was to investigate the effects of the carbonation phenomenon on durability properties of RCCP. In order to achieve this aim, RCC with 0.32 constant water-cement ratio in grades of 270, 300, 330 and 350 cement content were made and compressive strength tests, capillary absorption and carbonation resistance tests at the ages of 7, 28 and 90 days were carried out. If the carbon dioxide penetrates through RCC samples, the compressive strength decreases with regard to increasing the age of the samples. With the aging of samples, capillary water absorption is reduced due to the completion of the process of hydration which reduces the pores. The capillary absorption for carbonated samples compared with the same specimens relieve that carbonated and non-carbonated samples has few diffrence in terms of capillary water absorbtion. Overal the results which confirm each other suggest that, the increase in cement content have improved the durability parameters. It was also shown that carbonation phenomenon has not significant influence on physical performance and durability properties of RCCP. As a result, it can be said that the use of RCCP in urban environments where the phenomenon of carbonation is more likely, is permitted. This study also, encourages the application of RCCP in terms of resistance toward carbonation phenomon.