Mechanistic Properties of Hot-Mix Asphalt Mixtures Containing Hydrated Lime

Abstract

Permanent deformation and moisture damage are common distresses found in pavements today. The use of hydrated lime is known to decrease moisture susceptibility, and as a mineral filler it increases the stiffness of the mixture. The objectives of this study were (a) to evaluate the fundamental engineering properties of hot-mix asphalt (HMA) mixtures containing hydrated lime compared with conventional mixtures designed to meet the current Louisiana Superpave® specifications and (b) to evaluate the influence of hydrated lime on the mechanical properties of the resulting HMA mixtures. Nine 19.0-mm Level 2 HMA mixtures were designed and examined. Siliceous limestone aggregates that are commonly used in Louisiana were included in this study. The nine mixtures were divided into three sets; each set contained three mixtures. The first set included three mixtures that are conventional, as control mixtures, containing no hydrated lime and an SB polymer-modified asphalt cement meeting Louisiana specifications for PG 76-22M, PG 70-22M, and a neat PG 64-22. The second set included three mixtures that contained hydrated lime that was incorporated into the aggregate and asphalt cement mixture as slurry. The asphalt cements used were identical to the ones used in the first set, namely PG 76-22M, PG 70-22M, and conventional PG 64-22. The third set included three mixtures that contained hydrated lime that was blended dry with the asphalt cements used in the first and second sets, that is, PG 76-22M, PG 70-22M, and PG 64-22. Mechanistic tests were conducted to define the permanent deformation and endurance life of HMA mixtures with and without hydrated lime. The results indicated that the addition of hydrated lime as a mineral filler improved the permanent deformation characteristics of the asphaltic concrete mixtures. This improvement was particularly apparent at higher testing temperatures with mixes containing polymer-modified asphalt and limestone aggregate.

The mechanisms of hydrated lime modification of asphalt mixtures: a state-of-the-art review

“…In fact, it would be almost inexistent with a limestone aggregate. However, HL is known to improve the adhesion of the limestone aggregates as well (Huang, Robertson, Branthaver, & Petersen, 2005;Mohammad, Saadeh, Kabir, & Othman, 2008). So, other mechanisms must operate and especially those acting on the bitumen as described below.…”

Durability of bitumen binder reinforced with polymer additives: Towards upgrading Nigerian local bitumen

“…These investigations have revealed that the ageing mechanism of the asphalt binder is not yet fully understood. The loss in weight of bitumen as a result of the escape of light components would depend largely on the origin, type and the bitumen's composition [ 82 ]. Concerning composition, asphalt contains hydrocarbons, non-hydrocarbons and certain heteroatoms each having unique physicochemical properties and displaying a variety of decomposition temperatures during heating [ 83 ].…”

Study the Effect of Substitution Filler on performance of Asphalt Mixture

“…Wang et al (2018) [8] concluded in his research study that cement filler has a similar effect to that of mineral filler on volumetric and physical properties of asphalt mixture. Hydrated lime has been widely used for the improvement of resistance against moisture damage in asphalt binder but very limited work has been presented on the use of hydrated lime for modification of asphalt mixture [15][16][17]. The permanent deformation performance of asphalt mixture can be improved by adding hydrated lime as filler into asphalt mixture [18][19][20][21][22][23][24][25].…”