沥青老化机理综述

在查阅国内外相关资料的基础上,综述了沥青老化的主要机理。认为,沥青的化学组分变化是导致沥青＂变硬＂的外因,然而轻质组分的挥发和被吸收、各组分的氧化、聚合、沥青质的团聚以及改性剂的裂解才是导致组分变化和沥青老化的真正内因。     

沥青的老化与表征方法研究

通过分析沥青的老化机理,分析了影响基质沥青和改性沥青抗老化性能的因素,总结了目前研究沥青老化的方法以及评价沥青抗老化性能的方法。薄膜烘箱（TFOT）、旋转薄膜烘箱（RTFOT）以及压力老化容器试验（PAV）常用来模拟沥青的老化,并用沥青老化前后的宏观和微观结构的变化评价沥青的抗老化性能。     

埋地钢质管道石油沥青防护层老化机理猜想

以猜想方式描述分析了埋地长输管道石油沥青防护层的老化机理,解释了石油沥青防护层老化过程中实际存在的一些现象,为研究探讨长输管道石油沥青防护层老化过程提供了思路.     

道路沥青老化动力学的研究--以软化点为参数建立沥青老化动力学模型

研究了以辽河油田生产的稠油为基质沥青自制的两种沥青老化后软化点的变化，以软化点为参数建立了沥青一级老化动力学模型。并用该动力学模型对这两种沥青的抗老化性能进行了研究，求得了动力学参数。实验结果表明，这两种沥青老化后软化点均升高，AH-70沥青抗老化性能优于AH-90沥青，以软化点为参数建立的沥青老化动力学模型较好地表征了沥青老化过程，为研究沥青老化提供了一种简便可行的分析方法。     

基质沥青与 SBS 改性沥青的老化性能分析

以辽河AH90沥青为基质沥青,在其中加入质量分数为3%的苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性剂,可制备改性沥青。利用沥青软化点随时间的变化关系,建立了2种沥青的老化动力学模型:lnR基=3.784 1.33×103texp(-4946/T),lnR改=3.949 1.54×103texp(-5 242/T)。通过比较2种沥青的动力学参数,得出改性沥青的抗老化性能优于基质沥青。借助红外光谱分析可知,基质沥青的老化主要是吸氧氧化反应;而改性沥青的老化除了具有基质沥青的老化反应外,还存在SBS中聚丁二烯链段的断裂和氧化反应。     

石油沥青老化性能研究

采用薄膜烘箱（TFOT）在不同时间、不同温度下对五种代表性的沥青进行老化。通过对老化前后沥青的质量变化、针入度比、粘度比、沥青质含量的比较得到了五种沥青在不同条件下性质变化规律,提出了用质量损失表征抗老化性能和用延长薄膜烘箱试验时间模拟长期老化的不适宜性。     

高等级道路沥青老化动力学研究

在实验室研究了AH－70和AH－90两种高等级道路沥青在老化过程中,正戊烷沥青质及针入度、软化点、延度等指标的变化,并根据老化过程中,正戊烷沥青质的变化,进行了沥青老化动力学研究,计算得出了有关动力学参数,得到了沥青老化动力学方程,其计算值与试验数据相吻合。表明高等级道路沥青老化属于一级动力学反应。实际老化过程中针入度、软化点及延度的变化进一步证明了所得动力学模型是可靠的。     

沥青光氧老化研究进展

介绍了沥青的光氧老化机理，着重评述了现有的沥青及沥青混合料的光氧老化试验和老化后性能表征方法，阐述了改善沥青耐老化性能的途径。通过研究沥青光氧老化评价的方法，探索提高沥青抗光氧老化能力的途径具有重要的现实意义。     

改性沥青老化机理及再生剂的研究

基于改性沥青的老化机理基础上,试配了相应的再生剂,并进行系统的试验研究。研究认为,在改性沥青的老化过程中,基质沥青发生了挥发、氧化、聚合等物理化学反应,改性剂发生了氧化、裂解等反应,并最终导致改性沥青的路用性能大大降低。对再生剂的性能研究表明,以轻质油和重质油为主要成分的再生剂已不能满足改性沥青再生的要求,而添加交联组分、改性组分和渗透组分的新型再生剂,不仅与沥青的相容性好,而且大大提高了再生沥青的高、低温性能。     

碱性物质对沥青热老化的影响

对两种沥青进行薄膜烘箱试验（ＴＦＯＴ）和掺加碱性物质的ＴＦＯＴ试验，用沥青蒸发损失率随ＴＦＯＴ时间的变化、沥青化学组成的变化和沥青红外光谱的变化阐述沥青热老化的原因，时比沥青抗老化性能的优劣，考察线性物质对沥青热老化的影响．结果发现：碱性物质使沥青蒸发损失率降低，可能是碱性物质促进沥青吸氧所致；碱性物质促进沥青中重胶质和沥青质的生成，使沥青在１７Ｏｃｍ－１附近的红外吸收强度明显增强，进一步说明碱性物质促进沥青吸氧．沥青ＴＦＯＴ后其重胶质和沥青质增加程度及其在１７０ｃｍ－１处的红外吸收强度变化程度能够表征其抗吸氧老化性能优劣，反映沥青胶体体系变化程度．     

Development of an Asphalt Aging Procedure to Assess Long-Term Binder Performance

Abstract

Nine asphalts, including seven Strategic Highway Research Program asphalts and two Texas asphalts, were aged at several conditions of temperature and oxygen pressure to develop an aging test. Values for a dynamic shear rheometer function, a combination of both elastic and viscous properties that serves as an indicator of susceptibility to age-related pavement cracking, were measured for both aged and unaged samples. Each aging condition was ranked and calibrated against environmental room aging (60°C, 1 atm air), used to simulate road aging. PAV thin-film aging at 90°C, 20 atm air for 32 hr best represented environmental room aging.%     

Aging Behavior of Colored Paving Asphalt

In this paper, the aging processes of colored paving asphalt conforming to GB/15180-94 standard were studied by rotate thin film oven (RTFO) test. The results show that the established two dynamics models can be use to describe the aging velocity of the two kinds of colored paving asphalt perfectly. After aging, asphaltene content increased, resins and aromatics content, as well as saturate content decreased. As a result, the original colloidal structure of colored paving asphalt is destroyed, which deteriorates performance of the colored paving asphalt. During aging, the Gastel index (Ic), which is sensitive to aging conditions, decreased with increase of aging temperature and extension of aging time. Therefore, the Gastel index can be used to evaluate the aging resistance of the colored paving asphalt.     

生物柴油残渣对老化沥青物理性能的影响

利用生产生物柴油的残渣,经过物理分馏、冷凝过程获取可恢复老化沥青性能的生物再生剂。选择50号基质沥青进行短期老化试验,以沥青的针入度、软化点、延度为检验标准,发现添加生物再生剂的老化沥青性能可恢复到老化前标准;设定使再生沥青针入度恢复到50 1/10 mm的生物沥青掺量为最佳掺量,通过动态剪切试验(DSR)和沥青小梁弯曲试验(BBR)发现在最佳掺量条件下,再生沥青的高温抗变形能力和低温抗裂性均优于原50号基质沥青;与老化沥青相比,再生沥青高温抗变形能力略有下降,低温抗裂性大幅提高,证实了生物柴油残渣作为老化沥青再生剂的可行性。     

改性沥青的紫外老化研究

我国大部分地区尤其是西部地区日照时间长,太阳光谱中紫外线比例高,而紫外辐射同样也会导致沥青的老化。对传统基质沥青和SBS、消石灰、反应型三元共聚物(RET)及多聚磷酸(PPA)改性沥青的紫外老化特性进行了研究。试样的降解使用傅里叶变换红外光谱和热分析进行了分析,从红外光谱结果可以看出,当紫外老化200 h时,SBS、多聚磷酸(PPA)和消石灰改性沥青与传统基质沥青相比表现出更高的耐光降解能力。SBS改性沥青和消石灰改性沥青,老化后最大降解率的温度和降解终止温度增加。     

紫外老化对沥青流变性能的影响

This paper simulated the ultraviolet aging process of asphalt and used dynamic mechanic analysis （DMA） method to evaluate the effect of ultraviolet aging on the asphalt theological properties. After having experienced ultravio- let aging, the low temperature performance of asphalt binder decreased significantly, with its complex modulus increased and phase angle decreased along with changing rheological properties as compared to the performance of original asphalt binder. The ultraviolet aging process would make asphalt binder more sensitive to brittle and fatigue failure. On the basis of the time-temperature superposition principle （TTSP）, the viscoelastic transition frequency （coT） is proposed to evaluate the effect of ultraviolet aging. It is found that with the increase in ultraviolet aging time, the cox moves to the lower frequency range gradually. Since the viscoelastic transition frequency is sensitive to the effect of aging, it can be used as an indicator of ultraviolet aging.     

紫外线作用下道路沥青老化行为研究

为了研究紫外线老化下沥青性能变化,选取同种产地、不同标号的两种基质沥青以及两种常规改性沥青,分析基质沥青在不同紫外线老化后组分变化,研究四种沥青在不同时长紫外绒老化后的三大指标、DSR和BBR试验。结果表明,选用沥青老化后C/H值来评价同种来源基质沥青紫外老化性能是可行的,并可以通过使用DSR、BBR补充评价基质沥青和改性沥青紫外线老化后的高低温流变性能。     

Study on Aging Kinetics of Saudi Arabian Paving Asphalt

Abstract

The changes of n-pentane asphaltene content, penetration, softening point, and ductility of two Saudi Arabian paving asphalts have been studied during aging. Further, aging kinetics of asphalt, based on the change of n-pentane asphaltene content, has been studied. Some correlative kinetic parameters were calculated and the aging kinetics equation of asphalt was gained. The value calculated depending on the equation was in accordance with the experimental data. And the relationship between the composition of the high grade paving asphalt and its aging resistant performances was revealed. It showed that the aging of high grade paving asphalt was a first-order reaction. AH-70 paving asphalt has the following characteristics: higher reaction active energy, less reaction velocity constant, lower aging velocity, and better aging resistance performance compared with AH-90 paving asphalt. The changes of penetration, softening point, and ductility of asphalt during aging further proved that the kinetic model is reliable.     

Study on Aging Kinetics of Saudi Arabian Paving Asphalt

The changes of n-pentane asphaltene content, penetration, softening point, and ductility of two Saudi Arabian paving asphalts have been studied during aging. Further, aging kinetics of asphalt, based on the change of n-pentane asphaltene content, has been studied. Some correlative kinetic parameters were calculated and the aging kinetics equation of asphalt was gained. The value calculated depending on the equation was in accordance with the experimental data. And the relationship between the composition of the high grade paving asphalt and its aging resistant performances was revealed. It showed that the aging of high grade paving asphalt was a first-order reaction. AH-70 paving asphalt has the following characteristics: higher reaction active energy, less reaction velocity constant, lower aging velocity, and better aging resistance performance compared with AH-90 paving asphalt. The changes of penetration, softening point, and ductility of asphalt during aging further proved that the kinetic model is reliable.