Transitions of component, physical, rheological and self-healing properties of petroleum bitumen from the loose bituminous mixture after UV irradiation
Transitions of component, physical, rheological and self-healing properties of petroleum bitumen from the loose bituminous mixture after UV irradiation
复制标题
松散沥青混合物中石油沥青在紫外线照射后的组分、物理、流变和自修复性能的转变
DOI：
10.1016/j.fuel.2019.116507
复制
发表时间：
2020-02-15
期刊：
影响因子：
7.4
通讯作者：
Shu, Benan
中科院分区：
文献类型：
--
作者：
Li, Yuanyuan;Wu, Shaopeng;Shu, Benan
在沥青混合料中，石油沥青膜包裹在集料表面，很薄，这与纯沥青有明显区别。本研究以最常用的密实型沥青混合料AC-13为对象，进行紫外线（UV）辐照模拟试验。将松散沥青混合料分别暴露于紫外线照射下7、14和28 d，紫外线照射强度为21.0 w/m2。老化后的沥青用离心分离法回收，用薄层色谱-火焰离子化检测器（TLC-FID）对回收沥青（RB）的SARA组分进行了研究。同时，通过三大常规指标和动态剪切参数，研究了RB的物理流变性能。此外，通过复粘度扫频测试、毛细管测试和表面能测试，对紫外光辐照前后沥青的自修复性能进行了表征。结果表明，随着紫外光照射时间的延长，RB的化学成分发生明显变化，导致其胶体稳定性变差。与此同时，RB的物理流变性能发生了明显的转变（针入度、延性和相位角降低，软化点和复模量升高），表明RB的脆性和硬化程度增加。RB的流动性、毛管流动性和表面自由能均较低，导致沥青混凝土的自修复性能下降。
In the bituminous mixture, the petroleum bituminous film wrapped in the surface of aggregate is very thin, which is obviously different from the neat bitumen. In this research, the most commonly used dense bituminous mixture (AC-13) was designated for the ultraviolet (UV) irradiation simulation test. The loose bituminous mixture was exposed under the UV irradiation for 7, 14 and 28 days respectively, and the UV irradiation intensity was 21.0 w/m(2). After aging, the bitumen was recovered with the centrifuge separation method, the SARA components of the recovered bitumen (RB) was studied by the Thin-layer chromatography with flame ionization detection (TLC-FID). Meanwhile, the physical and rheological performance of the RB was investigated by the three major conventional indices and dynamic shearing parameters. In addition, the self-healing performance of bitumen was characterized by complex viscosity frequency-sweep test, capillary test and surface energy test before and after UV irradiation. The results show that with the extension of UV irradiation time, the chemical components of RB change obviously, which results in the deterioration of its colloid stability. Meanwhile, the physical and rheological performance of RB transitioned significantly (the decreases of penetration, ductility and phase angle of RB, and the increase of the softening point and complex modulus), indicates the RB becomes more embrittlement and hardening. Also, the worse flow behavior, the worse capillary fluidity and the lower surface free energy of RB result in the degradation of the self-healing performance of bituminous concrete.