Using a Single Test to Determine Specific Gravity and Absorption of Aggregate Blends
Using a Single Test to Determine Specific Gravity and Absorption of Aggregate Blends
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使用单一测试确定骨料混合物的比重和吸收率
DOI：
10.3141/1874-01
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发表时间：
2004
影响因子：
1.7
通讯作者：
K. Hall
中科院分区：
文献类型：
--
作者：
K. Hall
对于运输材料工程师来说，准确、一致地测量骨料比重的能力至关重要。由于测试时间长且存在变异性问题，当前的标准测试方法（AASHTO T-84 和 T-85）通常不用于常规质量控制目的。为测量比重和吸收率而开发的新技术之一是真空密封方法，该方法无需长时间浸泡，也无需在饱和表面干燥水分状态下测定骨料质量。真空密封方法还有可能在一次测试中测量骨料混合物的比重。通过传统方法和真空密封方法测量了由不同矿物学类型组成的六种粗骨料和四种细骨料的比重和吸水率。十种混合物的级配通常符合 Superpave® 热拌沥青规格，是通过使用各种集料组合创建的，并在一次真空密封测试中进行测试。对所有单独的骨料和混合物进行了五次重复测试。将骨料混合单次测试结果（比重和吸收率）与传统单独测试结果和数学组合获得的值进行比较。这些比较在方法之间产生了普遍很强的相关性，表明真空密封程序有望成为一种相对快速的方法，用于在骨料混合物的单次测试中确定比重和吸收率。然而，测试值的一些实际差异表明真空密封方法需要改进才能无缝替代传统方法。
The ability to measure the specific gravity of an aggregate accurately and consistently is paramount to transportation materials engineers. Current standard test methods (AASHTO T-84 and T-85) typically are not used for routine quality control purposes because of long testing times and questions about variability. Among new techniques developed for measuring specific gravity and absorption is a vacuum-sealing method, which eliminates the need for long soaking periods and for determining aggregate mass in a saturated-surface-dry moisture state. The vacuum-sealing method also has the potential to measure the specific gravity of a blend of aggregates in a single test. Specific gravity and absorption of six coarse and four fine aggregates composed of various mineralogy types were measured by both traditional and vacuum-seal methods. Ten blends, whose gradations generally met Superpave® hot-mix asphalt specifications, were created by using various combinations of aggregates and tested in a single vacuum-seal test. Five replicate tests were done on all individual aggregates and blends. Aggregate-blend single-test results (specific gravity and absorption) were compared with values obtained with traditional individual test results and mathematical combinations. The comparisons yielded generally strong correlations among methods, indicating the vacuum-seal procedure has promise as a relatively rapid method for determining specific gravity and absorption in a single test of an aggregate blend. However, some real differences in test values suggest that the vacuum-seal method needs refinement before it can be seamlessly substituted for traditional methods.