A REVIEW OF THE USE OF RECLAIMED ASPHALT PAVEMENT FOR ROAD PAVING APPLICATIONS

One of the most frequently used waste materials is reclaimed asphalt pavement (RAP). The use of RAP can help reduce the cost of a project and ensure that the project is eco-friendly. Therefore, the aim of this study is to give a detailed description of the production of RAP to ensure that the rehabilitation and maintenance of pavements as well as the construction of pavements are environmentally friendly and cost effective. Previous works have shown the benefits of using RAP with regard to its ability to produce equally good or even superior results compared to the use of virgin or original mixes if they are properly produced and applied. Among the benefits of RAP mixes are good moisture resistance and higher density. This review also demonstrate the critical importance of using RAP in asphalt mixtures.

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Evaluation of Reductions in Fume Emissions (VOCs and SVOCs) from Warm Mix Asphalt Incorporating Natural Zeolite and Reclaimed Asphalt Pavement for Sustainable Pavements

Sustainability ◽

10.3390/su12229546 ◽

2020 ◽

Vol 12 (22) ◽

pp. 9546

Author(s):

Javier Espinoza ◽

Cristian Medina ◽

Alejandra Calabi-Floody ◽

Elsa Sánchez-Alonso ◽

Gonzalo Valdés ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Natural Zeolite ◽

Asphalt Pavement ◽

High Energy ◽

Asphalt Mixtures ◽

Reclaimed Asphalt Pavement ◽

Reclaimed Asphalt ◽

Volatile Organic ◽

Road Paving

Conventional asphalt mixtures used for road paving require high manufacturing temperatures and therefore high energy expenditure, which has a negative environmental impact and creates risk in the workplace owing to high emissions of pollutants, greenhouse gases, and toxic fumes. Reducing energy consumption and emissions is a continuous challenge for the asphalt industry. Previous studies have focused on the reduction of emissions without characterizing their composition, and detailed characterization of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) in asphalt fumes is scarce. This communication describes the characterization and evaluation of VOCs and SVOCs from asphalt mixtures prepared at lower production temperatures using natural zeolite; in some cases, reclaimed asphalt pavement (RAP) was used. Fumes were extracted from different asphalt mix preparations using a gas syringe and then injected into hermetic gas sample bags. The compounds present in the fumes were sampled with a fiber and analyzed by gas-liquid chromatography coupled to mass spectrometry (GC/MS). In general, the preparation of warm mix asphalts (WMA) using RAP and natural zeolite as aggregates showed beneficial effects, reducing VOCs and SVOCs compared to hot mix asphalts (HMA). The fumes captured presented a similar composition to those from HMA, consisting principally of saturated and unsaturated aliphatic hydrocarbons and aromatic compounds but with few halogenated compounds and no polycyclic aromatic hydrocarbons. Thus, the paving mixtures described here are a friendlier alternative for the environment and for the health of road workers, in addition to permitting the re-use of RAP.

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Laboratory comparative assessment of warm and hot mixes Asphalt containing reclaimed Asphalt pavement

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol8.iss2.164 ◽

2020 ◽

Vol 8 (2) ◽

pp. 15-26

Author(s):

Hasan H Joni ◽

Aqeel Y M Alkhafaji

Keyword(s):

Asphalt Pavement ◽

Asphalt Mixture ◽

Warm Mix Asphalt ◽

Asphalt Mixtures ◽

Reclaimed Asphalt Pavement ◽

Moisture Resistance ◽

Recycled Asphalt ◽

Reclaimed Asphalt ◽

Marshall Stability ◽

The Impact

Warm mix Asphalt (WMA) could be mixed and used in paving at low temperatures to minimize the consumption of energy and the emissions of greenhouse gas. Recycled Asphalt pavement (RAP) could save Asphaltic cement and aggregate, which could achieve the better effects of recycling. However, both of the two WMA and RAP technologies have some deficiencies. Warm mix Asphalt and Reclaimed Asphalt pavement (WMA-RAP) technique may solve these issues and deficiencies when they are utilized together. This study investigated the implementations of WMA-RAP and its impacts on the performance of the Asphalt mixture. Under the framework of this study, four percentages of RAP (0%, 20%, 30%, and 40%) were added to the hot mix Asphalt (HMA) and WMA containing 4% Sasobit to study the impact of increasing RAP content on Marshall stability and moisture resistance of Asphalt mixtures. In summary, the Marshall stability of HMA and WMA mixtures is higher than the control mixtures. A small decrease in moisture resistance of both (HMA and WMA) containing RAP comparing to control mixtures Asphalt was observed, as shown by reduced the tensile strength ratios (TSR), but it is still much higher than the minimum of 80%.

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