Research on highly dissolved rubber asphalt prepared using a composite waste engine oil addition and microwave desulfurization method

Using recycled rubber waste in the construction of asphalt pavements not only improves pavement performance, but also promotes sustainable development. Consequently, rubber asphalt pavements have received significant attention in recent years. However, conventional rubber asphalt has numerous disadvantages such as low solubility, high viscosity, uneven dispersion, and poor storage stability. In this study, a composite method involving waste engine oil addition and microwave desulfurization to prepare highly dissolved rubber asphalt was proposed. Four types of rubber asphalt-conventional rubber asphalt, microwave-treated rubber asphalt, rubber asphalt with added waste engine oil, and highly dissolved rubber asphalt using the proposed composite method-were prepared and tested. The solubility, rheological properties, and storage stability of the prepared rubber asphalt specimens were studied. Specifically, the extraction of undissolved rubber was used to characterize the solubility of rubber asphalt. The results demonstrate that the solubility of the highly dissolved rubber asphalt prepared using the composite method was around 40%, which is 10%-20% higher than that of conventional rubber asphalt. The lowtemperature performance and storage stability of the highly dissolved rubber asphalt improved significantly, and it also exhibited good high-temperature performance. The findings obtained herein indicate that the proposed composite treatment method for waste crumb rubber can significantly improve the performance of rubber asphalt, thereby promoting the application of rubber asphalt in the construction of asphalt pavements. (C) 2021 Elsevier Ltd. All rights reserved.