Asphalt Mixes Processed with Recycled Concrete Aggregate (RCA) as Partial Replacement of the Natural Aggregate

Abstract

Materials play a fundamental role in any branch of civil engineering. From ancient times to the present day, society has required enormous amounts of construction materials, which implies an excessive exploitation of the natural environment. The present research work consisted in the design and development of asphalt mixes with a partial substitution of the natural aggregate (NA) by means of recycled concrete aggregate (RCA). The mix was designed with the Marshall methodology, considering the next percentages of substitution and addition by mass: 90% NA and 10% RCA; 80% NA and 20% RCA; 70% NA and 30% RCA. The mixtures were elaborated and analysed under the international standards and the Mexican regulation of the Communications and Transport Ministry, to determine the best option regarding their performance. The materials were characterized according to the current regulations and later employed in the mixes design. A total of 38 specimens were elaborated for each mixture, determining the optimum asphalt content; after that, mechanical tests were performed to analyse and determine the best results. In the aftermath of the examination of all mixtures, we concluded that the 70%AN/30%RCA is the best alternative option according to its performance and numeric results, complying with the cited regulations, and allowing a lower content of asphalt during the process.

Investigation on the effect of moisture induced damage on asphaltic concrete mix incorporating waste concrete aggregates

“…Waste concrete aggregates can be used in hot-mix asphalt as a partial replacement for natural aggregates to address these problems while maintaining environmental sustainability. The environmental objective is to reuse and recycle these materials which could generate beneficial economic activities with proper treatment [8].…”

Mechanical and Environmental Performance of Asphalt Concrete with High Amounts of Recycled Concrete Aggregates (RCA) for Use in Surface Courses of Pavements

“…In fact, these aggregates have already attracted interest for application in different layers and types of mixtures, mainly in bituminous base and binder courses [19], as well as in dense/semi-dense asphalt mixtures [20], in stone mastic asphalt (SMA) [21], and even in porous asphalt (PA) [22]. In the meantime, its use has been extended to a wide variety of production methods, namely, cold asphalt mixes (CMAs) [23], foamed asphalt mixtures (FAMs) [24], and warm mix asphalt (WMA) [25][26][27], in addition to "traditional" hot mix asphalt (HMA) [28][29][30][31][32]. However, it was also noted that its use in high percentages of incorporation in mixtures for surface layers has not been shared, with only two references describing laboratory studies [21,33].…”

Evaluation of Modulus of Rupture of the Concrete with Addition of PET Fibers and Polypropylene

“…Multiple investigations have also been carried out to improve and evaluate the performance of different modified materials [6] and to increase the durability of the pavement [7,8].…”