Improving the performance of porous asphalt with reclaimed asphalt, dune sand and lime

Abstract

A porous asphalt pavement is an open-graded asphalt mix that allows rainwater to drain through the surface layer. When designing a pavement structure, the porous asphalt layer is generally not taken into consideration due to its poor mechanical characteristics. The objective of this research study was to reuse reclaimed asphalt pavement in a porous asphalt mixture and then to improve the performance of the resulting mix by adding dune sand and lime. Several porous asphalt mixes with the addition of different percentages of reclaimed asphalt, dune sand and lime were tested. The results obtained showed an improvement in the mechanical performance of the tested porous asphalt mixes, especially when using 40% reclaimed asphalt, 10% dune sand and 1% lime. Marshall stability and Duriez compressive strengths increased when compared to the values obtained with a reference porous asphalt mixture, by 42 and 66%, respectively, while the flow decreased by 30%. In addition, except for the splitting tensile strength, all other studied mechanical characteristics were better than those of the ordinary well-graded hot-mix asphalt.

Concrete Made with Dune Sand: Overview of Fresh, Mechanical and Durability Properties

“…The strength differential might be more than 10%, depending on the DS/FA ratio [ 34 ]. Since the compressive capacity has greatly increased and the tensile strengths have only marginally diminished, it was possible to create a material that may be considered when constructing pavement constructions by adding dune sand and lime to permeable asphalt [ 49 ]. At all evaluated ages up to 44 percent, the recycled aggregate made from concrete waste used to make the dune sand mortar had lower tensile strength than the specimen mortar.…”

Experimental and Numerical Studies of Viscoelastic Behavior of Bituminous Mixture with a High Rate of Reclaimed Asphalt Pavement, Dune Sand and Lime

“…Despite its advantages, RAP is still considered as waste and is rarely used in road construction in North African countries [24][25][26]. This work is a continuation of previous investigations that have aimed to better prediction of the viscoelastic behavior of asphalt mixtures incorporating high RAP content, and other additions such as dune sand and lime [13,17,19,20]. In this paper, a new formula that contains 40% of RAP, 10% of dune sand and 1% of hydrate lime is proposed and tested to evaluate its mechanical behavior and compare it to that of the conventional mixes.…”

“…They have also concluded that the addition of 10% of dune sand to the asphalt mixes containing 40% of RAP can significantly improve the mechanical characteristics of the mixtures in terms of Marshall stability and flow, water resistance, and compaction behavior [20]. However, they revealed in a later study a small decrease in the splitting tensile strength of mixtures containing high RAP and dune sand compared to the conventional mixtures [13].…”

“…However, a decrease in the splitting tensile strength of the bituminous mix, was noted, beyond this 40% rate of RAP. Beyond this content, the Marshall flow, the compressive strength and the splitting tensile strength have decreased mainly because of the excess of aged bitumen, considered as hard material, and the reduction of virgin bitumen [13]. An investigation conducted by Mogawer and al [14] has showed that above 40% of RAP cracking resistance was reduced as the percentage of RAP material increased.…”

“…In fact, lime allows to increase the deformation resistance, stiffness and rutting resistance [17,20] and to reduce the chemical ageing of the bitumen and limit its oxidation [21,22]. Siala and al. have demonstrated that the addition of 1% of hydrate lime to an asphalt mix containing 40% of RAP and 10% of dune sand improves the mechanical performances, in particular, the Marshall creep and the resistances in water and air [13]. A reduction of the production temperature has also been noted to approach the manufacturing temperature of warm-mix asphalt (WMA) [17], which deals with concerns about global warming and energy consumption.…”