高等级道路沥青延展性及调合组分的选择

通过对高等级道路沥青的基础沥青（溶剂脱油的软沥青及硬沥青）和调合组分（抽出油、中东减渣１及中东减渣２、油浆）进行物理性质、化学组成及ＧＰＣ分子量测定，质谱族组成分析，阐述了影响沥青薄膜烘箱（ＴＦＯＴ）后１５℃延度大小的因素。经过调合后的沥青物性指标表明，作为高等级道路沥青的调合组分，中东减渣１比中东减渣２具有更优越的调合性能；抽出油作为沥青调合组分，调合出的沥青ＴＦＯＴ后延度＞１５０ｃｍ；催化油浆经过改质也可以作为与抽出油相当的理想调合组分，但长期的沥青老化性能与路用性能是否理想仍有待于进一步研究。     

石油沥青及其组分吸氧老化中化学组成和结构的变化

考察了单家寺和胜利直馏100号道路石油沥青及其组分在吸氧老化中化学族组成和平均结构参数的变化,结果表明,沥青的各组分变重,平均分子量增大;各种试样平均分子中的总碳数、总环数、缩合指数和芳香度增加;胶质和沥青质组分变化最明显,是沥青中最不稳定的组分;沥青吸氧确为缩合反应。两种沥青相比,吸氧量较多的胜利沥青及其组分的变化明显高于单家寺沥青及相应组分的变化。     

石油沥青及其组分吸氧老化中化学组成结构的变化

详细考察了单家寺和胜利直馏道路沥青(100号)及其组分在吸氧老化中化学族组成和平均结构参数的变化。结果表明,沥青的各组分变重,平均分子量增大;各种试样平均分子的总碳数、总环数、缩合指数和芳香度增加;胶质和沥青质组分变化最明显,是沥青中不稳定的组分。两种沥青相比,吸氧量较多的胜利沥青及其组分的变化明显高于单家寺沥青及其相应组分。     

原位红外研究沥青的热氧老化过程

用四组分法将沥青分为饱和分、芳香分、胶质、沥青质。采用原位红外研究了四组分在不同气氛下的热氧老化过程。研究表明，在氮气氛围下，各组分均无明显老化现象。在氧气中，饱和分和芳香分的热氧化速度最快，在空气中次之。在氧气或空气中，胶质和沥青质的热氧老化程度很弱。同时分别在饱和分和芳香分中加入一定量的不同添加剂，通过研究其热氧老化过程考察添加剂对饱和分和芳香分抗氧化性能的影响。     

紫外线吸收抗老化剂在沥青中的应用研究:老化动力学模型的建立

为了能够简捷、直观地评价加入紫外线吸收抗老化剂的沥青的抗老化性能，本研究建立了以正戊烷沥青质含量为参数的老化动力学模型。通过考察老化过程中正戊烷沥青质含量的变化，计算得到了有关动力学参数，建立了老化动力学模型，比较了加入抗老化剂的沥青以及原沥青的抗老化性能。     

矿化度对放射性密度—含水率计响应的影响

射线穿过不同物质后，物质对射线吸收的程度可用放射性密度－含水率计来测定。不同矿化度的流体，其离子浓度不同，因而对射线吸收的程度不一样。矿化度试验发现，当在蒸馏水中国盐使矿化度达到８００００ｍｇ／ｋｇ时，密度变化值为０．０４ｇ／ｃｍ＾３，含水率变化值为２．４％。大庆地区的地下水一般属ＮａＨＣＯ３水型。     

石油沥青抗老化性能研究

采用薄膜烘箱试验、低温吸氧试验、自然老化试验及反相气液色谱对国产典型的石油沥青及组分进行了老化和加速老化试验。根据沥青老化前后物化性质及其变化，如粘度比、吸氧量、凝胶渗析色谱峰扩展、族组成的变化、含氧基团的变化及老化综合指数等评价了国产沥青的抗老化性能。建立了沥青吸氧动力学模型。初步讨论了提高沥青耐久性的途径     

生产优质高等级道路沥青的探索

以中东进口原油的减渣为原料，经溶剂脱沥青得到脱油沥青，并将其作为基本组分与改性油浆等富含芳烃的组分调合，生产符合ＧＢ／Ｔ１５１８０－９４的高等级道路沥青，并且薄膜烘箱试验后的１５℃延度大于１００ｃｍ，其质量与进口沥青相当。     

中间相沥青显微结构的研究

用热台偏光显微镜（ＨＳＭＯ）对乙烯渣油中间相沥青（ＥＴＭＰ）和澄清油中间相沥青（ＤＯＭＰ）的显微结构进行了静态观察，对ＥＴＭＰ和ＤＯＭＰ经四氢喹啉（ＴＨＱ），加氢改性后氢化沥青热动态中形成的显微结构及其变化进行了研究；用Ｘ－光衍射（ＸＲＤ）技术研究了中间相沥青，氢化改性中间相沥青的晶格参数及变化；通过显微结构的研究，对制备高性能碳纤维的原料－中间相沥青作了初步的评价。     

水包稠油乳状液中孤岛稠油组分间相互作用初探

 研究了孤岛稠油脱沥青质油、胶质、沥青质及胶质与沥青质混合物对水包稠油乳状液界面性质的影响。结果表明，具有高芳碳率、低烷基碳率、高芳香环缩合程度的沥青质组分界面活性较高。在水包稠油乳状液形成过程中，芳香分的存在有利于以稠合芳香环系为核心的胶质粒子的溶解，促进胶质单元结构在油滴表面的吸附，使脱沥青质油的界面活性高于胶质。胶质对沥青质有很好的分散作用，使沥青质在油相中溶解度增加，沥青质分子以较小的缔合体或以自由分子状态存在，沥青质分子中所有极性基团较易到达表面上，使油水界面张力降低。稠油组分与阴离子乳化剂LAS存在正的协同作用，与非离子乳化剂OP-10存在负的协同作用。稠油各组分共同与乳化剂作用形成稳定的水包稠油乳状液。     

Effect of Chemical Nature on the Susceptibility of Asphalt to Aging

The knowledge of the factors affecting the susceptibility of asphalt to aging can be of help when selecting the asphalt binders for the construction of durable pavements. Investigated were the aging-induced changes in the chemical composition and colloidal nature of asphalts differing in origin and technology. It was shown that the course of the changes in the generic composition of asphalt upon aging under laboratory conditions depends on the chemical type of the feedstock from which the asphalt has been derived. During aging of the asphalts from the paraffin-naphthenic crudes, the resins undergo partial decomposition, which results in the increase of the cyclic fraction content. Although the increase of the asphaltene content in air-blown asphalts after the Thin Film Oven Test was found to be lower than that in the corresponding straight-run asphalts, the much higher value of the instability index and smaller size distribution of asphaltenes in the air-blown asphalts permit us to expect that their utilization as binders in pavement construction will lead to the reduction of pavement durability. It follows from the results of this study that not only the generic composition but also the structure of the fractions affect the resistance of asphalt to aging.     

Effect of Chemical Nature on the Susceptibility of Asphalt to Aging

Abstract

The knowledge of the factors affecting the susceptibility of asphalt to aging can be of help when selecting the asphalt binders for the construction of durable pavements. Investigated were the aging-induced changes in the chemical composition and colloidal nature of asphalts differing in origin and technology. It was shown that the course of the changes in the generic composition of asphalt upon aging under laboratory conditions depends on the chemical type of the feedstock from which the asphalt has been derived. During aging of the asphalts from the paraffin–naphthenic crudes, the resins undergo partial decomposition, which results in the increase of the cyclic fraction content. Although the increase of the asphaltene content in air-blown asphalts after the Thin Film Oven Test was found to be lower than that in the corresponding straight-run asphalts, the much higher value of the instability index and smaller size distribution of asphaltenes in the air-blown asphalts permit us to expect that their utilization as binders in pavement construction will lead to the reduction of pavement durability. It follows from the results of this study that not only the generic composition but also the structure of the fractions affect the resistance of asphalt to aging.     

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。     

RTFOT与TFOT对沥青胶结料热老化程度的影响

通过分析老化沥青残留物的质量变化，针久度，粘度，车辙因子和低温蠕变性能，比较RTFOT和TFOT条件下沥青胶结料热老化程度的差异，结果表明：TFOT残留物在常温和高温下的粘度及车辙因子平均水平均低于RTFOT残留物，但低温性能呈现出不同的行为，影响程序取决于沥青品种，当对沥青进行PG分级时，若沥青性能指标接近临界值时，不能忽 视两种老化条件引起的差异，否则容易出现误判。     

Influence of Chemical Composition on the Physical Characteristics of Paving Asphalts

The simplest general compositional model considers asphalt to be made up of asphaltenes, heavy oils, and resins. In the present study the extent of similarity between the properties and composition of various types of asphalt obtained from different sources has been carefully explored. It shows how ductility, penetration, and softening point are related to the chemical nature of paving asphalts in the range 41-58 softening points. Asphalt properties are found to be a direct function of its chemical constituents. The relationship between softening point and asphaltene content was found to be linear while asphalts of the same softening point are easily distinguished by the content of the resins. Evaluation of the two asphalt indices—the asphaltene index (I_A) and the Gaestel index (I_C), reveals that they both vary linearly with the composition of asphaltenes and resins thus confirming their suitability in the characterization of asphalts. Comparison of the two indices shows that IC is more suitable in estimating the colloidal stability of different groups of asphalts. The observed correlations can be found useful in the areas of asphalt blending and rejuvenating through the appropriate selection of asphalt components.     

TLA改性沥青流变和老化性能的研究

采用动态剪切流变仪（DSR）对不同掺量的11A改性沥青的流变性能进行了研究,并通过薄膜烘箱老化（TFOT）和紫外老化（uv）试验研究了TLA对沥青老化性能的影响。结果表明：加入TLA后,沥青的复数模量增大,相位角减小,TLA的掺量每增加10％,PG高温区间基本上升1个等级,大大提高了沥青的高温稳定性和降低了其温度敏感性。与未改性沥青相比,TLA改性沥青TFOT和UV老化后的软化点增量和粘度变化指数显著减小,TFOT老化后的残留针入度比明显增大,TLA的加入有效地改善了沥青的热氧老化和紫外老化性能。     

Influence of Chemical Composition on the Physical Characteristics of Paving Asphalts

Abstract

The simplest general compositional model considers asphalt to be made up of asphaltenes, heavy oils, and resins. In the present study the extent of similarity between the properties and composition of various types of asphalt obtained from different sources has been carefully explored. It shows how ductility, penetration, and softening point are related to the chemical nature of paving asphalts in the range 41–58 softening points. Asphalt properties are found to be a direct function of its chemical constituents. The relationship between softening point and asphaltene content was found to be linear while asphalts of the same softening point are easily distinguished by the content of the resins. Evaluation of the two asphalt indices—the asphaltene index (I _A ) and the Gaestel index (I _C ), reveals that they both vary linearly with the composition of asphaltenes and resins thus confirming their suitability in the characterization of asphalts. Comparison of the two indices shows that IC is more suitable in estimating the colloidal stability of different groups of asphalts. The observed correlations can be found useful in the areas of asphalt blending and rejuvenating through the appropriate selection of asphalt components.     

STUDY OF SERIAL REACTION KINETICS AND CHANGES OF GROUP COMPOSITIONS OF PETROLEUM ASPHALTS IN CONTINUOUS HEAT AND AIR AGING

The serial reaction kinetics and the changes of group compositions of Shengli petroleum asphalt(SPA) and Huansanlian petroleum asphalt(HPA) were studied during continuous heat and air aging(CHAA) at 120 ∼ 180°C. The test results show that at given temperature the contents of saturate constituents of two asphalts change very little, aromatic constituents decrease clearly and asphaltenes increase gradually during CHAA. At lower temperatures(120 ∼ 140 °C) the contents of resins increase slowly and no toluene insolubles form obviously, but at higher temperature(180°C) the resins increase at first and then decrease and the toluene insolubles increase much quickly with the CHAA time. The higher the CHAA temperature, the more evidently the change of asphalt group compositions would change. The apparent aging rate constants and the apparent aging activation     

Study on Aging Capability of Paving Asphalt

The changes of softening point, penetration, and ductility of two asphalts after aging were studied. Two methods are simultaneously used to study the aging kinetics of two asphalts and some kinetic parameters are given in this paper. The results show that the softening points increase while penetration and ductility values decrease after aging. It was concluded that the aging capability of AH-70 asphalt is better than AH-90 asphalt. The aging kinetic models of two asphalts based on softening points are compared with a pentane asphaltene aging kinetic model and the results are consistent. A new and easy method for studying the aging of asphalt was developed.     

SIZE EXCLUSION CHROMATOGRAPHY STUDIES OF AGED SHRP ASPHALTS

One of Ihe objectives of the Strategic Highway Research Program is the development of a test procedure that accurately predicts pavement aging. In order to accomplish this goal, the nature and mechanism of oxidative-aging of asphalts must be known.

Eight asphalts were aged in a pressure-oxidation vessel at 60°C (140°F) and 2.07 x 10⁶ Pa (300 psi) for 144 hours (6 days) after a preliminary thin-film oven treatment. The tank asphalts and aged asphalts were separated by preparative size exclusion chromatography into two fractions: one consisting of large molecular size, associated molecules and the other consisting of smaller molecules with less tendency lo associate. The amount of the large molecular size fraction is greater in an aged asphalt compared with its parent tank asphalt. Number-average molecular weights of this large molecular size fraction increase substantially in some aged asphalts but not in others. Viscosities of smaller molecular size fractions (which comprise the bulk of both aged and unaged asphalts) of aged asphalts are not greatly different from viscosities of corresponding fractions of parent tank asphalts. Viscosities of the small molecular size fractions are much lower than viscosities of whole asphalts. Oxygen-containing functional groups were observed in both size exclusion chromatography fractions of all eight aged asphalts.

The above results can be rationalized by invoking a model of asphalt structure in which complex structural units composed of polar and/or aromatic molecules arc dispersed in a less polar solvent phase. The aping process causes buildup of more polar molecules, which increases the relative amounts of asphalt components that engage in associative behavior.