沥青温拌性能的变速拌和试验评价研究

Study on Evaluation of Warm Mixing Asphalt Effect by Variable Speed Mixing Test

摘要: 沥青温拌技术的应用符合节能减碳发展战略，在沥青路面铺筑中逐渐得到了较多应用。为了定量评价沥青温拌剂的温拌效果，论文研究采用70^#沥青和SBS改性沥青为基础沥青，添加表面活性类温拌剂Alube (掺量0.7%)和有机降黏类温拌剂ACMP (掺量7%)，制备了温拌沥青及其AC-13沥青混合料，测试了温拌沥青的技术性能，利用自主开发的沥青混合料变速拌和试验装置，试验研究了在不同温度下，沥青混合料的拌和流动特性，理论上提出了沥青混合料的拌和流动模型，基于混合料的等黏温度差，评价了温拌沥青的温拌效果。研究结果表明：(1) 沥青混合料的拌和流动性服从宾汉流变模型，变速拌和试验从流变理论上引入了拌和塑限与拌和黏度两个流动参数，通过分析混合料的黏温曲线及等黏温度差，能够定量评价温拌沥青的温拌性能；(2) 有机降黏类温拌剂ACMP使得沥青的针入度和延度增大、软化点和黏度下降，而表面活性类温拌剂Alube对沥青的技术性能几乎没有影响；(3) 温拌剂能够改善沥青混合料的拌和流动性，降低混合料的拌和温度17℃~25℃，表明变速拌和试验能够有效评价温拌混合料的温拌效果，值得推荐标准化应用；(4) 有机降黏类温拌剂的掺入，对同类沥青混合料的路用性能略有弱化，而表面活性类温拌剂对沥青混合料的路用性能则有所改善。

Abstract: The application of warm mixing asphalt technology conforms to the development strategy of energy saving and carbon reduction, and it has been gradually applied in asphalt pavement. In order to quantitatively evaluate the warm mixing effect of warm mixing asphalt additive, this paper used 70^# asphalt and SBS modified asphalt as the base asphalt, added chemical additive Alube (content 0.7%) and organic additives ACMP (content 7%), prepared warm mixing asphalt and its AC-13 asphalt mixture, and tested the technical performance of warm mixing asphalt. The mixing flow characteristics of asphalt mixture at different temperatures were studied experimentally by using the self-developed variable speed mixing test device of asphalt mixture. The mixing flow model of asphalt mixture was proposed theoretically. Based on the equal-viscosity temperature difference of the mixture, the warm mixing effect of warm mixing asphalt was evaluated. The results show that: (1) Mixing flowability of asphalt mixture follows Bingham rheological model. Two flow parameters, mixing plastic limit and mixing viscosity, are introduced from rheological theory in the variable speed mixing test. By analyzing the viscosity-temperature curve and equal-viscosity temperature difference of the mixture, the warm mixing performance of warm mixing asphalt can be evaluated quantitatively. (2) ACMP increases the penetration and durability of asphalt, and decreases the softening point and rotational viscosity, while Alube has little effect on the technical properties of asphalt. (3) The warm mixing agent can improve the mixing flow of asphalt mixture and reduce the mixing temperature of the mixture by 17˚C~25˚C, indicating that the variable speed mixing test can effectively evaluate the warm mixing effect of the warm mixing mixture, and it is worth recommending standardized application; (4) The addition of organic additive weakened the pavement performance of similar asphalt mixture slightly, while the chemical additive improved the pavement performance of asphalt mixture.