ABSTRACT

The influence of hydrated lime on moisture susceptibility of asphalt mixture was assessed using a combination of surface energy measurements and modified saturation ageing and tensile stiffness test. Four aggregate types, which are commonly used for manufacturing asphalt mixtures in the UK have been selected. These aggregates were from various rocks across the UK which includes felsic intrusive, calcite sedimentary, mafic extrusive and argillaceous sandstone rock sources. Two out of four aggregate sources including felsic intrusive, and argillaceous sandstone showed improvement with the hydrated lime replacement, however the performance of aggregates from calcite sedimentary, mafic extrusive rocks remained unaffected. Mineralogy test results, showed significant differences among four aggregate types used in this study. The difference in the behaviour of four aggregate types to the hydrated lime replacement can be credited in part to mineralogical composition of different aggregates. The hydrated lime content of 1% was observed better than 2% in the aggregates who showed improved performance with the use of hydrated lime. The trends obtained in the surface energy measurements have been found similar to saturation ageing and tensile stiffness (SATS) test technique. The results clearly illustrate a close agreement between both techniques used in this study for the evaluation of moisture susceptibility.

摘要

熟石灰对沥青混合料湿敏性的影响采用表面能测量和改进的饱和老化和拉伸刚度试验相结合的方法进行了评估。已经选择了四种在英国通常用于制造沥青混合料的骨料类型。这些聚集体来自英国各地的各种岩石，包括长英质侵入岩、方解石沉积岩、镁铁质喷出岩和泥质砂岩岩源。四分之二的骨料来源，包括长英质侵入岩和泥质砂岩，随着熟石灰的替代而有所改善，但方解石沉积岩、镁铁质喷出岩的骨料性能未受影响。矿物学测试结果表明，本研究中使用的四种骨料类型之间存在显着差异。四种骨料类型对熟石灰替代物的行为差异部分归因于不同骨料的矿物组成。在显示使用熟石灰改善性能的骨料中，观察到 1% 的熟石灰含量优于 2%。已发现在表面能测量中获得的趋势类似于饱和老化和拉伸刚度 (SATS) 测试技术。结果清楚地说明了本研究中用于评估水分敏感性的两种技术之间的密切一致性。在显示使用熟石灰改善性能的骨料中，观察到 1% 的熟石灰含量优于 2%。已发现在表面能测量中获得的趋势类似于饱和老化和拉伸刚度 (SATS) 测试技术。结果清楚地说明了本研究中用于评估水分敏感性的两种技术之间的密切一致性。在显示使用熟石灰改善性能的骨料中，观察到 1% 的熟石灰含量优于 2%。已发现在表面能测量中获得的趋势类似于饱和老化和拉伸刚度 (SATS) 测试技术。结果清楚地说明了本研究中用于评估水分敏感性的两种技术之间的密切一致性。