Laboratory investigation on performance of waste-oil cutback asphalt as prime coat on cement stabilized macadam base

• Published in: Construction & building materials 2023-02, Vol.365, p.129965, Article 129965
• Main Authors: Ren, Kaijie, Liu, Chaochao, Wu, Zhengda, An, Hao, Qu, Jianjiao, Zhang, Honggang, Lv, Songtao
• Format: Article
• Language: English
• Subjects: Emulsified asphalt; Kerosene cutback asphalt; Prime coat material; Semi-rigid base; Waste-oil cutback asphalt
• ISSN: 0950-0618
• DOI: 10.1016/j.conbuildmat.2022.129965

•Waste-oil cutback asphalt as a new kind of prime coat material was developed.•The road performance of waste-oil cutback asphalt prime coat material was analyzed and evaluated by comparing with that of traditional prime coat materials.•The optimum construction conditions of the waste-oil cutback asphalt prime coat material were determined by studying road performance. The commonly used prime coat materials have shortages such as insufficient interlayer bonding performance, high cost, and serious environmental pollution. To solve the above problems, this study attempts to take waste-oil as the diluent and blend it with asphalt to prepare a new prime coat material: waste-oil cutback asphalt. And the feasibility of this prime coat material is studied on semi-rigid base. Through penetration test, direct shear test, and pull-out test, the optimum blending proportions and construction conditions of the waste-oil cutback asphalt are determined, and the feasibility of the waste-oil cutback asphalt was evaluated by comparing it with kerosene cutback asphalt and PC-2 emulsified asphalt. The results illustrate that the mass ratio of waste-oil to asphalt is 1:1, and the content of penetrant is 10 % of the asphalt mass (47.6 % waste-oil, 47.6 % asphalt, 4.8 % penetrant in the percentage of 100 %) can be used as the optimum blending proportion of waste-oil cutback asphalt. The average penetration depth of waste-oil cutback asphalt is 5.4 mm, which meet the standard requirements. The direct shear strength is 0.292 MPa, which is 23.7 % and 86.0 % higher than that of PC-2 emulsified asphalt and kerosene cutback asphalt. And the pull-out strength is 0.235Mpa, which is 11.4 % and 92.6 % higher than that of theirs. The optimum construction condition is 1.1 L/m2, and the best construction time is 1 day after the construction of the base course. It indicated the interlayer bonding performance of waste-oil cutback asphalt is significantly improved than traditional prime coat materials. Thus, the waste-oil cutback asphalt can be used as a new type of environmentally friendly and high-performance prime coat material on cement stabilized macadam base.