This study aims to investigate the effect of cationic asphalt emulsion (CAE) as an admixture on durability characteristics of roller compacted concrete (RCC). To this aim, the CAE was added to the RCC mixture at 0%, 2%, 4%, 6%, 8%, and 10% of the cement mass; these mixtures were designed by the maximum density method according to ASTM D1557. The cubic and cylindrical specimens were fabricated using vibrating hammer; water absorption, sorptivity, water penetration depth, and electrical resistivity tests were conducted to evaluate the durability of the mixtures. The water penetration test was carried out on cubic specimens in accordance with BS EN 12,390-8: 2009; moreover, by cutting each cylindrical specimen, two 100 x 50 mm discs for conducting sorptivity and one 100 x 100 mm cylinder for conducting the water absorption and electrical resistivity tests were prepared. The results indicated that the decrease in the water absorption, penetration and sorptivity, and the increase in the electrical resistivity of the mixtures can be obtained by increasing the CAE content. Also, the analysis of variance (ANOVA) at 95% confidence level based on Dunnett comparison procedure denoted a significant improvement in the RCC transport properties by adding CAE. Scanning electron microscope (SEM) images were studied and it was revealed that filling the capillary pores and coating the inner surface of larger pores with asphalt exhibited a change in the structure of cement paste pores and demonstrated an improvement in the transport properties of the RCC. Performing electrical resistivity test is of great importance for evaluating the durability of concrete due to its non-destructive and rapid properties. Therefore, intrinsically linear regression models were estimated between its results and other durability indicators, which show proper fits based on their coefficient of determination (min[R.sup.2] > 0.83). The findings revealed that electrical resistivity test can be employed to estimate the various transport properties of the RCC.
Roller compacted concrete
Water penetration depth
Scanning electron microscopy
Roller compacted concrete (RCC) is defined as a type of concrete that, in its unhardened state, is able to support a roller while being compacted. The amount of cement paste required in this concrete is just as much as filling the voids between the aggregates and the water content is designed for having enough workability . The first implementation of roller-compacted concrete pavement (RCCP) dates back to 1930 in Sweden . In North America, the first experience with the construction of RCCP occurred in 1942 during the construction of an airport runway in Washington. However, in Canada, the RCC was first used as a surface layer in 1976 in the construction of a log sorting yard. The initial design was a layer of stabilized aggregates with a thickness of 14 in. as the base layer and 2 in. of asphalt concrete surface. However, a pavement with a thickness of 14 in. consisting of an 8 in. stabilized base with 8% cement and 6 in. aggregates with 13% cement was built upon...