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Linwood, NJ, United States

Adaptation and mitigation are the two critical actions that are needed to counter the looming threats of climate change on transportation. For roadways, flooding constitutes one of the most important impacts of climate change, and adaptation to build more resilient roadways must be made. For a proper adaptation, the first step is a way to properly assess the vulnerability of roadways to flooding. Road construction impacts the environment negatively through emissions and energy consumption, and a proper way to determine the practical methods to reduce the impact is also necessary. This paper presents a framework to assess the vulnerability of roadways to flooding and evaluate the impact of different changes in construction on energy consumption and emission. Two system dynamics based models were developed and results of the simulations have been presented. Simulation tools for these two models have also been developed and made available on the public domain. The results of the simulation point out the beneficial effects of providing low permeability and dense and thick surface layers to reduce vulnerability to flooding and that of using drier aggregates, reducing heat losses, reduced mix temperatures and extension of pavement lives on the emission and energy consumption during roadway construction. © 2015 Vilnius Gediminas Technical University (VGTU) Press Technika.

Zaumanis M.,Worcester Polytechnic Institute | Mallick R.B.,Worcester Polytechnic Institute | Frank R.,RAP Technologies
Resources, Conservation and Recycling | Year: 2014

A holistic evaluation of the feasibility of producing 100% recycled mixtures is presented. Eleven technologies readily available for producing 100% Reclaimed Asphalt Pavement (RAP) hot asphalt mixtures are described in the article and the complementary video (http://youtu.be/coj-e5mhHEQ). The recorded performance of 100% RAP mixtures is analyzed along with identification of typical high RAP distresses. Recommended mix design procedures and the best RAP management strategies are described. A cradleto- gate analysis of environmental effects indicated 18 kg or 35% CO2eq savings per t of produced 100% RAP asphalt mixture compared to virgin mix, while cost analysis showed at least 50% savings in material related expenses. © 2014 Elsevier Ltd. All rights reserved.

Mallick R.B.,Worcester Polytechnic Institute | Radzicki M.J.,Worcester Polytechnic Institute | Zaumanis M.,Worcester Polytechnic Institute | Frank R.,RAP Technologies
Resources, Conservation and Recycling | Year: 2014

A significant amount of mineral aggregates are used in constructing, rehabilitating and maintaining roads. As local (nearby) quarries get exhausted, aggregates need to be hauled from sources that are at ever-greater distances. Hence, over time the cost of trucking as well as the amount of emissions generated by trucking increases with a decrease of local natural aggregate stocks. The objectives of this study are to construct and utilize a system dynamics model of the depletion of a stock of natural aggregates due to pavement construction and maintenance, and determine the effect of using local and nonlocal aggregates, recycling and project cancellation (slowing growth) on the paving of roads. Long-term simulations are carried out with available aggregate stock, trucking distance and cost data. The quality of roads and a sustainability score, based on engineering, economic and environmental factors (emissions) are evaluated for different scenarios. An optimal combination of the use of local and nonlocal recycled aggregates, recycling and project cancellation is recommended. The proposed system dynamics model could be utilized by agencies to plan for the proper utilization of aggregate resources for road development and maintenance/rehabilitation projects. © 2014 Elsevier B.V.

Zaumanis M.,Worcester Polytechnic Institute | Mallick R.B.,Worcester Polytechnic Institute | Frank R.,RAP Technologies
Construction and Building Materials | Year: 2014

The changes in Superpave performance grade (PG) of Reclaimed Asphalt Pavement (RAP) binder were determined after addition of two doses of six rejuvenators. The high and low PG temperatures were reduced linearly with an increased dose while the penetration grew exponentially. It was found that the grade sum of rejuvenated RAP binder is always higher than that of the corresponding virgin binder. Based on these conclusions a procedure for optimizing the rejuvenator dose to satisfy the Superpave PG requirements was developed to account for the inevitable variability of the RAP binder due to differences in aging and source. © 2014 Elsevier Ltd. All rights reserved.

Zaumanis M.,Worcester Polytechnic Institute | Mallick R.B.,Worcester Polytechnic Institute | Frank R.,RAP Technologies
Materials and Structures/Materiaux et Constructions | Year: 2015

Because of aged binder, high reclaimed asphalt pavement (RAP) content mixes are susceptible to cracking failures and are less workable than virgin mixtures. The potential of six differently originated recycling agents was evaluated in this study to restore the desired binder properties using conventional binder test methods and the results were compared with performance-related test results of 100 % RAP mixture. Binder test results showed that application of organic products require much lower dose to provide the same softening effect as petroleum products. The workability of binder and mixture was improved compared to RAP, but remained lower than that of reference virgin mixture. All rejuvenated mixtures proved to be very rut resistant. Low temperature performance of RAP, measured by creep compliance at −10 °C, was improved with the application of all recycling agents and RAP mixes rejuvenated with waste vegetable products even performed equal or better than virgin mixture. Organic oil and both waste vegetable products provided the best performance in binder and mixture fatigue resistance tests as measured by linear amplitude sweep and fracture work density respectively. Overall, the organic products outperformed the petroleum based additives in most tests, which partly can be attributed to un-optimized recycling agent dose. It was observed that penetration test may be a good indicator for initial selection of optimum dose since the results provide indication of rut resistance as well as fatigue performance of mixture and can be easily predicted using an exponential relationship that was developed in the research. © 2014, RILEM.

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