University of Qom Civil Infrastructure Researches 2783-140X 10 2 2024 12 21 Mechanical Performance of Roller-compacted Concrete Containing Recycled Asphalt Aggregate and Nano-Silica Mechanical Performance of Roller-compacted Concrete Containing Recycled Asphalt Aggregate and Nano-Silica 179 199 3182 10.22091/cer.2024.11343.1575 FA Mahmoud Malakouti Olounabadi Department of Civil Engineering, Persian Gulf University, Bushehr, Iran. 0000-0002-0779-9340 Milad Jahanbazi Department of Civil Engineering, Persian Gulf University, Bushehr, Iran. 0000-0000-0000-0000 Seyed Shaker Hashemi Department of Civil Engineering, Persian Gulf University, Bushehr, Iran. 0000-0003-2560-5025 Babak Golchin Department of Civil Engineering, University of Mohaghegh Ardabili, Ardabil, Iran. 0009-0006-6081-215X Ramin Meshkabadi Faculty of Advanced Technologies, University of Mohaghegh Ardabili, Ardabil, Iran. 0000-0001-8329-6190 Journal Article 2024 09 18 Roller-compacted concrete, a type of concrete with zero slump, is being used in road pavement construction. The use of recycled asphalt in roller-compacted concrete is an enviromental approach for reducing emissions. This study examines the impact of recycled asphalt aggregate and nano-silica on the strength behavior of roller-compacted concrete. Cylindrical samples were fabricated to determine optimal moisture content and maximum dry density. The compressive strength, along with stress and strain curves at optimal moisture, were evaluated. Additionally, the surface area under the stress-strain curve and energy absorption were measured. Results indicate that adding asphalt aggregates decreases the optimal moisture content in roller-compacted concrete. Conversely, nano-silica increases the optimal moisture content and enhances the maximum dry density of the samples. Replacing recycled asphalt with coarse aggregate revealed a decrease in compressive strength of roller-compacted concrete samples at both 7 and 90 days. Moreover, nano-silica did not improve the reduced compressive strength, with its negative impact being more pronounced at 90 days than at 7 days. The study also found that recycled asphalt increases the area under the stress-strain curve and enhances energy absorption. However, adding nano-silica to control samples and those with recycled asphalt does not improve ductility or energy absorption. Roller-compacted concrete, a type of concrete with zero slump, is being used in road pavement construction. The use of recycled asphalt in roller-compacted concrete is an enviromental approach for reducing emissions. This study examines the impact of recycled asphalt aggregate and nano-silica on the strength behavior of roller-compacted concrete. Cylindrical samples were fabricated to determine optimal moisture content and maximum dry density. The compressive strength, along with stress and strain curves at optimal moisture, were evaluated. Additionally, the surface area under the stress-strain curve and energy absorption were measured. Results indicate that adding asphalt aggregates decreases the optimal moisture content in roller-compacted concrete. Conversely, nano-silica increases the optimal moisture content and enhances the maximum dry density of the samples. Replacing recycled asphalt with coarse aggregate revealed a decrease in compressive strength of roller-compacted concrete samples at both 7 and 90 days. Moreover, nano-silica did not improve the reduced compressive strength, with its negative impact being more pronounced at 90 days than at 7 days. The study also found that recycled asphalt increases the area under the stress-strain curve and enhances energy absorption. However, adding nano-silica to control samples and those with recycled asphalt does not improve ductility or energy absorption. https://cer.qom.ac.ir/article_3182_8c8eb0de794c81c84bb8c48e6e6ec7fd.pdf