Determination of Polycyclic Aromatic Compounds in Asphalt and in Corresponding Leachate Water

The environmental impact of polycyclic aromatic compounds (PACs) in asphalt (bitumen) materials is related to their availability for environmental transport and biouptake, rather than their total concentrations. This study examines six Strategic Highway Research Program (SHRP) paving asphalts and four commercial roofing asphalts. Three cleanup procedures for the neat asphalt samples are evaluated. This study reports on analyses for 29 PACs, including the EPA 16 priority pollutant PAHs and additional Persistent Bioaccumulative Toxins. These require reporting by the U.S. EPA under the Emergency Planning and Community Right-to-Know Act (EPCRA) section 313. The analytical protocol for analysis of the higher molecular weight PACs by GC/MS is reported, with inclusion of GC/MS/MS verification of some of the detectable compounds. Additionally, each asphalt was taken through a toxicity characteristic leaching procedure following U.S. EPA method SW846-1311. Results of the paving and roofing asphalts and their corresponding leachate waters are presented in this study.     

催化裂化油浆在生产优质道路沥青中的应用

催化裂化作为主要的重油加工技术在石油加工中的地位十分重要 ,催化油浆的有效合理利用是一个迫切需要解决的问题。催化裂化油浆富含芳香分和胶质 ,结合这一性质特点 ,对催化油浆掺入渣油中通过溶剂脱沥青生产优质道路沥青的技术方案进行了研究。结果表明 ,油浆和渣油本身的性质对脱油沥青性质有很大影响 ,渣油掺兑油浆后溶剂脱沥青可使脱油沥青的针入度提高 ,延度明显改善 ,达到改善脱油沥青性质的目的。选取 3种减压渣油和两种催化裂化油浆 ,在适宜的油浆掺兑比并控制一定的脱沥青油收率 ,可以获得优质道路沥青 ,同时还可以使道路沥青的蜡含量降低 ,生产合格的重交道路沥青。     

硫酸钙晶须在道路改性沥青中的应用研究(Ⅰ)

研究了不同改性剂处理的硫酸钙晶须用量、沥青改性工艺因素以及基质沥青属性等对道路沥青性能的影响规律.结果表明,改性后的硫酸钙晶须能明显提高沥青的软化点,降低沥青的针入度,并且随改性剂添加量的增加沥青软化点逐渐增加,其针入度逐渐减小.本研究为沥青改性提供了一类新材料,同时也为硫酸钙晶须的应用研究奠定了基础.     

AR—20沥青改性剂性能评价

介绍了沥青改性剂AR－20的基本性能，考察了AR－20对沥青性能的影响，以及对沥青混合料的抗车辙能力、对沥青与碎石粘结力的改善作用。     

Study on Composition and Structure of Liaoshu Asphalt

In this article, the structure characteristics of Liaoshu paving asphalts have been studied by the methods of element analysis, SARA and E-D-M. At same time, the relation between composition and structure and using performance of Liaoshu paving asphalt were established. The experimental results show that carbon and hydrogen contents were more than 95%, the hydrogen/carbon atom ratio was about 1.5 in the Liaoshu paving asphalts. The content of saturates is between 20 and 25% in the Liaoshu paving asphalt, aromatics 35-40%, resin 25-30%, and asphaltene 8-10%. There are 45 carbon atoms in asphalt average molecule, which contain 16-17 aromatic carbon atoms. The number of total ring in asphalt average molecule is 5-6, the aromatic ring is 3-4, the naphthene ring is 1-2.     

剪力墙结构的自由网格划分

本文针对剪力墙结构提出了一种新的自由网格划分方案,使得剪力墙结构的有限元离散模型更加合理,从而提高有限元分析的精确性和可靠性。该方案以铺砌法自由网格算法为核心并联合几何拆分法和映射网格法,兼顾自由网格的通用性和映射网格的高效性,既满足各种复杂结构模型的要求,又提高网格划分的质量,并同时确保网格划分的速度,从而节省结构分析的总时间。     

地面铺装更具人性化若干要素

随着时代的变迁,城市的风貌也在不以人的意志为转移而发生着变化,对于人行道及广场的规范建设,人们总在期待人性化舒适度不断提高。她们的铺装以追求愉悦色彩、创意和图案,富有人性的让步行成为一种乐趣的人行道和广场与建筑物、树街道及风景的和谐是大家追求的目标。本文将从几个方面探求以人为本的地面铺装艺术问题。     

A Study on Aging Kinetics of Asphalt Based on Softening Point

Abstract

Asphalt aging is a nonreversible first order reaction, and the extent of asphalt aging is usually expressed by the increase of its softening point. In this article, the first order aging kinetic model of asphalt has been put forward based on softening points of asphalt at different aging time, and the kinetic parameters have been obtained. The results showed that the aging of asphalt could be described with softening point and belonged to first order kinetics, which offered a available and convenient method for studying the asphalt aging behavior. The aging resistance of two paving asphalts were also compared by this model.     

具有热稳定性SBS改性道路沥青的研制

沙中AH - 70沥青具有芳香分含量高等特点 ,根据苯乙烯 -丁二烯 -苯乙烯嵌段共聚物 (SBS)与沥青中的芳香烃组分相容性最好的特性 ,通过高速剪切机将SBS聚合物溶于沙中AH - 70沥青中 ,经过高速搅拌得到SBS和基质沥青均匀的混合物。再将单质硫、ZnO和 2 -巯基苯并噻唑作为稳定剂与通过液 -固吸附色谱柱分离技术从安庆循环催化裂化废油中分离出富芳香分油混合 ,制成稳定剂母液 ,在一定条件下 ,加入到SBS和基质沥青的混合物中 ,研制出了符合交通部JTJ0 36 - 98系列中的I -D类技术要求的SBS改性道路沥青产品。离析实验结果表明热储存稳定性达到技术标准要求 ,而且具有良好的感温性能、高温稳定性能、低温抗裂性和抗老化性能     

两种道路沥青抗老化性能的比较

研究了鞍山半氧化道路沥青的老化过程 ,提出了 2种沥青的动力学模型。通过对老化后 2种道路沥青使用性能、粘度以及胶体不稳定指数的变化 ,比较了它们的抗老化性能的优劣 ,并对道路沥青的老化机理进行了分析。结果表明 ,所提出的动力学模型能够很好的描述 2种道路沥青的老化速率。由dx/dt(AH - 90 ) >dx/dt(AH- 70 )可以初步证明AH - 70的抗老化性能优于AH - 90。老化后 ,AH - 70的针入度、软化点变化率均小于AH - 90的相应指标 ,AH - 70的老化指数也小于AH - 90的老化指数 ,这些都证明了AH - 70的抗老化性能好于AH - 90的抗老化性能。随着沥青老化的进行 ,沥青各组分都向着更重的方向转化 ,沥青质含量增加 ,沥青胶体的原有平衡结构遭到破坏 ,导致沥青使用性能变差