Laboratory evaluation properties of HMA modified with carbon Nano tube

Laboratory evaluation properties of HMA modified with carbon Nano tube

In this study, along the lines of the use of different polymeric and non-polymeric materials in improving the characteristics of bitumen and asphalt mixtures, carbon Nano-tube as a new material is used to increase the life and improve the performance of asphalt mixtures due to its unique properties (100 times more resistant than steel) and the fact that its molecular structure is very close to that of bitumen. For preparing bitumen modified with carbon Nano-tube, it is necessary to specify the appropriate conditions of mixing this material with bitumen. Therefore, to meet this need, three different types of mixer and for each of which three states of combination are considered. For the samples mixed by the ultrasonic mixer, it is observed that the Nano-materials are uniformly and separately from each other (without being agglomerated) spread in bitumen. The use of Nano-materials improves the classic properties of bitumen (softening point, penetration degree and so on) in comparison to the base bitumen. In the next step, the asphalt samples are prepared using the modified bitumen and then, their Marshall stability, indirect tensile strength, and rutting are investigated. In addition, the resistance and performance of these samples in to water (moisture sensitivity) is surveyed since the issue of contacting with water is inevitable for asphalt mixtures due to water penetration into the asphalt through the pore of pavements and also water penetration and leakage through slits and cracks on pavements.