Evaluation of asphalt properties in plant produced asphalt mixes

工厂生产的沥青混合料中沥青性能的评估

• 批准号: 530444-2018
• 负责人: Tighe, Susan
• 金额: $ 2.11万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=697727
• 关键词: Evaluation; asphalt; properties; plant; produced

The Ontario Ministry of Transportation (MTO) is responsible for the safety and quality of Ontario's highway network. 95% of this network is paved with hot mix asphalt (HMA): a material produced with heated stone, sand, or gravel bound together with asphalt cement, a product of crude oil. In Ontario, asphalt cement properties have been accepted based on performance grading to the American Association of State and Highway Transportation Officials (AASHTO) standards since the adoption of the Superpave technology in early 2000's. However, the aging protocols included in the AASHTO standard, which are intended to simulate the short term (production and placement) and longer term (in service) oxidative aging of asphalt cement, have been shown to not correlate with field aging. In 2009, the Bituminous Section of the Materials Engineering Research Office (MERO) of the MTO added new tests to provide better characterization of asphalt materials and prediction of asphalt pavement performance in Ontario. A study was conducted to evaluate the new tests and how well they correlate with performance - the study concluded that correlation to field for both the current and new tests could be improved, if field aging can be better replicated in the lab. Nonetheless, the new test methods have been adopted by MTO for acceptance. Testing is carried out on asphalt cement samples collected from HMA producers' asphalt tanks. In addition, some municipalities in Ontario have further modified this specification, applying them to recovered asphalt cement from HMA. That is, the asphalt binder is removed or extracted from the aggregates in the HMA mix by using a solvent, then the asphalt is recovered from the solution for testing. There are concerns with the appropriateness of acceptance criteria based on recovered asphalt cement, because research has shown that the extraction and recovery process can impact the asphalt cement properties, and there is no understanding of how the recovered asphalt properties compare to the original virgin asphalt. Accurate material characterization is important for engineers and owners to predict performance. Therefore, the overall objective of this research is to provide a framework for characterizing of asphalt cement and HMA by: firstly, comparing current laboratory aging protocols to field aging of asphalt cement; and second how the measured properties of the asphalt cement and HMA correlate to performance. The study will also include a review of test results reported by various industry testing labs, to assess the range in test results between labs, to understand the testing variability associated with material characterization of recovered asphalt.

安大略省运输部（MTO）负责安大略省高速公路网络的安全和质量。该网络的95％用热混合沥青（HMA）铺成：一种由加热的石材，沙子或砾石与沥青水泥结合在一起的材料，这是原油的产物。 在安大略省，自2000年代初采用SuperPave技术以来，根据美国州和公路运输官员协会（AASHTO）标准的绩效评分，已经接受了沥青水泥物业。但是，旨在模拟沥青水泥的短期（生产和放置）和长期（服务）氧化衰老的衰老方案，旨在模拟短期（生产和放置）和长期（服务中）与现场衰老无关。 2009年，MTO材料工程研究办公室（MERO）的沥青部分添加了新的测试，以更好地描述沥青材料以及安大略省沥青路面性能的预测。进行了一项研究，以评估新测试以及它们与性能的关系如何 - 如果在实验室中可以更好地复制现场衰老，则可以改善与当前和新测试的现场相关性。 但是，MTO已采用了新的测试方法来接受。对从HMA生产者的沥青罐收集的沥青水泥样品进行了测试。 此外，安大略省的一些市政当局进一步修改了此规范，将其应用于从HMA中恢复的沥青水泥。也就是说，通过使用溶剂从HMA混合物中的聚集体中除去沥青粘合剂，然后从溶液中恢复沥青进行测试。 人们担心基于回收的沥青水泥的接受标准的适当性，因为研究表明，提取和恢复过程可能会影响沥青水泥的特性，并且对恢复的沥青特性与原始的原始沥青相比如何不了解。 准确的材料表征对于工程师和所有者预测性能很重要。因此，这项研究的总体目的是为沥青水泥和HMA的表征提供一个框架：首先，将当前的实验室老化方案与沥青水泥的现场老化进行比较；其次，测量沥青水泥和HMA的特性与性能相关。 该研究还将包括对各种行业测试实验室报告的测试结果的综述，以评估实验室之间的测试结果范围，以了解与回收沥青的材料表征相关的测试变异性。