糠醛抽出油再生沥青的流变和感温性能研究

Study on Rheological and Temperature Sensitive Properties of Recycled Asphalt from Furfural Extraction Oil

为了解糠醛抽出油作为沥青再生剂对不同老化程度沥青的再生效果,对糠醛抽出油再生沥青的流变性能和感温性能进行研究。通过将糠醛抽出油添加到轻度、中度和重度3种不同老化程度的沥青中,采用动态剪切流变试验和弯曲蠕变试验,研究糠醛抽出油对老化沥青的流变性能及感温性能的影响规律,并以不同指标对再生沥青的流变性能和感温性能进行评价。研究结果表明:随着糠醛抽出油掺量的增加,老化沥青的中温抗疲劳性能和低温抗开裂性能均得到提升,高温抗变形性能则降低;不同老化程度的沥青在合适的糠醛抽出油掺量下性能能够恢复至基质沥青水平;多重应力蠕变试验对沥青高温抗变形性能的评价比车辙因子更适用;疲劳因子与线性扫描振幅试验对沥青中温抗疲劳性能的评价结果一致;再生沥青的感温性能在不同的温度区间具有不同的表现,在46~76℃时,随着糠醛抽出油掺量的增加,3种再生沥青的感温性能均增强;在-18~-6℃时,蠕变速率指数对感温性能的评价结果比蠕变劲度指数好,重度老化再生沥青的感温性能随着糠醛抽出油掺量的增加而增强,轻度和中度老化再生沥青的感温性能则相对减弱。以各项指标基本恢复到基质沥青水平为标准确定的最佳掺量为轻度老化4%,中度老化7%,重度老化8%。

In order to find out the regeneration effect of furfural extraction oil as asphalt regeneration agent on asphalt with different aging degrees,the rheological properties and temperature sensitivity of furfural extraction oil recycled asphalt were studied.By adding furfural extraction oil to asphalt with mild,moderate and severe aging degrees,the dynamic shear rheological tests and bending creep tests were used to study the influence of furfural extraction oil on the rheological properties and temperature sensitivity of aged asphalt,and the rheological properties and temperature sensitivity of recycled asphalt were evaluated with different indexes.The results showed that with the increase of furfural extraction oil content,the middle temperature fatigue resistance and low temperature crack resistance of aging asphalt were improved,and the high temperature deformation resistance was reduced.The performances of asphalt with different aging degree could be restored to the level of matrix asphalt under suitable furfural extraction oil content.The multiple stress creep test was more suitable for evaluating the high temperature deformation resistance of asphalt than the rutting factor.The evaluation results of the fatigue factor and linear scanning amplitude test on mesothermal fatigue resistance of asphalt were consistent.The temperature sensitivity of recycled asphalt had different performance in different temperature ranges.In the temperature range of 46-76℃,with the increase of furfural extraction oil content,the temperature sensitivity of three kinds of recycled asphalt was enhanced.In the temperature range of-18--6℃,the evaluation results of the creep rate index on the temperature sensitivity were better than those of the creep stiffness index.Temperature sensitivity of severe aging recycled asphalt increased with the increase of furfural extraction oil content,while the temperature sensitivity of mild and moderate aging recycled asphalt decreased.With the basic recovery of each index to the same as the virgin asphalt,the optimum content was determined as mild aging 4%,moderate aging 7%,severe aging 8%.