An Analysis of Reclaimed Asphalt Pavement from a Single Source—Case Study: A Secondary Road in Romania

Abstract

The paper presents a comprehensive analysis on reclaimed asphalt pavement (RAP) milling material collected from a single source, namely from a secondary road in Romania, county road DJ109. The following characteristics are investigated: particle size, binder content, material variability and uniformity, and the clustering phenomena. Variability is demonstrated using the results of particle size gradation and binder content. The coefficient of uniformity and the coefficient of curvature demonstrate that the RAP used in this research is a well-graded material. However, the visual analyses conducted on RAP highlight the presence of RAP particle agglomeration and the need for further testing. The study presents three different experimental phases: (i) RAP-milling old asphalt pavement, RAP; (ii) RAP milling after binder extraction, RAPabe; and (iii) RAP after Los Angeles crushing, RAPac. After processing, the coarse part (C) had a great influence on the fine part (F), and F/C ratio increased, respectively, from 0.4 to 1.5 and 1.61. Material variability on the extended site, the difference between the design values and particle size, as well as the existing clustering process indicated that RAP material collected from secondary roads must be pre-processed prior to its storage and reuse in the recycling process. Considering that secondary roads represent 71% of the overall network of asphalt course roads in Romania, and around 24,000 km of roads are in need of at least extensive maintenance (wearing asphalt courses) or rehabilitation, RAP is a highly recyclable material. Therefore, this study provides advice and guidance for re-using RAP in new pavement mixtures.

Eco-Innovative Concrete for Infrastructure Obtained with Alternative Aggregates and a Supplementary Cementitious Material (SCM)

“…The splitting tensile strength was determined using the formula: (10) where: f ct,sp -tensile splitting strength in MPa; F-maximum load in N; l-length of the contact line of the specimen in mm; d 1 and d 2 -size of the cross-section in mm.…”

“…The uncontrolled consumption of natural resources may have led to the climate and economic changes we are already facing, which are the result of the still-existing linear economies in certain areas of the world [4]. The increasingly large volume of waste in landfills, the lack of storage space, and the stringent reduction of non-renewable natural resources are strong motivations for researchers to mobilize and support recyclers in finding innovative ways to use recycled waste as raw materials in new concrete mixes, which represents one of the most eco-friendly options [5][6][7][8][9][10].…”

Analysis of the cold recycling asphalt pavements method from Romania

“…Most importantly, the reused raw material does not need to be dried or heated, which means that compared to conventional recycling methods it produces a fuel saving, cold recycling also allows the use of binders to be reduced by up to 50 % -the area of greatest potential savings, as binders are still the biggest cost factor in road rehabilitation [3]. With cold recycling technology, the material removed from the road surface is immediately recycled and reused, the logistics for this procedure are minimal and the duration of construction sites where cold recycling "in situ" is envisaged is considerably shorter than for conventional road rehabilitation projects.…”

The Influence of Blast Furnace Slag on Cement Concrete Road by Microstructure Characterization and Assessment of Physical-Mechanical Resistances at 150/480 Days

“…It is estimated that worldwide demand for construction aggregates is over 10 billion tons annually [41,42]. Much research explores the durability of concrete containing recycled aggregates (RAC) from building demolition [43,44], from road asphalt pavements (RAP) [45][46][47], quarry sand (QS) [48], or ecological mortars in which natural aggregates have been replaced by glass waste [49].…”