PROJECT DESCRIPTION
BACKGROUND
In 2005, 76% of the total population of Western Europe - or 141 million people - lived in urban areas. By 2030, it is projected that this figure will have increased to 81.7%. One of the key impacts of greater numbers in our urban spaces is increased demand on urban transport networks. Authorities are confronted with the challenge of reconciling the ever-growing need for transport with the desire for sustainable cities. Increased transport is typically associated with environmental problems such as air and noise pollution, which can also have a significant negative impact on human health and well-being. The construction of roads produces several specific environmental challenges. The OECD estimates that 10 000 m3 of aggregates are needed for each kilometre of two-lane road and large amounts of fossil fuels are consumed. Road construction is thus associated with the consumption of raw materials and the generation of a number of air pollutants, including particulate matter (PM), nitrogen oxides (NOx), sulphur oxides (SOx), carbon monoxide (CO), volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and carbon dioxide (CO2).
OBJECTIVES
The LIFESURE project aimed to minimise the consumption of natural resources in road construction, by producing and demonstrating the effectiveness of an innovative technology for manufacturing eco-asphalt on site. The project aimed to develop a prototype on-site asphalt plant using reclaimed asphalt pavement (RAP) as raw material. The aim was to test a total of 18 000 m2 of low-speed (<50 km/h) road with 100% RAP eco-asphalt in surface and binder layers against standard hot-mix asphalt, both on a test track and under real conditions on a Madrid street. The project beneficiaries sought to demonstrate that LIFESURE eco-asphalt can improve the environmental performance of urban roads, reducing greenhouse gas emissions and noise pollution, whilst reducing the consumption of raw materials and costs for road authorities.
RESULTS
LIFESURE developed, demonstrated and evaluated an innovative technology to fully recycle asphalts for use in eco-asphalts on roads, which was shown to be technically feasible, cost-efficient and more sustainable than the existing technologies.
The project beneficiaries manufactured their half-warm mix eco-asphalts at a relatively low temperature (<100ºC), using only 0.03 tonnes of binder added per tonne of recycled milled asphalt, with less or no additional natural aggregates. The beneficiaries designed the formulas for the asphalts tested during the project: a) control, a conventional hot-mix asphalt (AC16D); b) LIFESURE eco-asphalt using 100% reclaimed asphalt pavement (RAP); and c) LIFESURE eco-asphalt using 70% RAP and 30% natural aggregates. They also designed and constructed a prototype plant for making half-warm mixes of recycling asphalt on-site, which was used to manufacture the eco-asphalts tested on the test track of project partner CEDEX, and on three demonstration stretches of the street Méndez álvaro in Madrid. Sensors were embedded in the asphalt mixes to monitor their behaviour.
Evaluation of the CEDEX test track showed that the eco-asphalts were not as long-lasting as conventional hot mix asphalt, being stiffer and less flexible. However, the results obtained up to the project end date for the evaluation in the street in Madrid showed that there were no significant differences between the two LIFESURE eco-asphalts (100% and 70% RAP) and the conventional hot-mix asphalt, as the three stretches had similar performances. Therefore, the LIFESURE eco-asphalts are technically feasible to be used on urban roads.
The project beneficiaries also developed an economic assessment, which concluded that the LIFESURE eco-asphalts are cheaper to manufacture than conventional asphalts. The Life Cycle Assessment also revealed that the LIFESURE eco-asphalts are more efficient in terms of carbon emissions. The demonstration of the technical feasibility of cost-efficient eco-asphalts that are more sustainable than the existing hot-asphalt mixes ensures that the project’s outcomes have a very high replication potential.
In terms of environmental benefits, the LIFESURE technology enables the manufacturing of asphalt mixes with reduced energy consumption (manufacturing temperature <100ºC), while recycling 70-100% of used asphalt milled material. Therefore, the project contributes to reducing the consumption of raw materials, saves energy, contributes to the construction of more sustainable roads, and reduces greenhouse gas (GHG) emissions.
The project is relevant to EU and national policies regarding waste reduction, the circular economy and climate change mitigation. To this end, the project team drafted guidelines and recommendations towards the regulation of the use of recycled asphalts. They also developed a study to standardise the use of the LIFESURE eco-asphalts, and drafted a set of recommendations to include criteria for the selection of recycled asphalts in Green Public Procurement procedures. The social benefits due to the project include its contribution to building more sustainable roads and cities, and reduced GHG emissions. Citizens will also benefit because road construction/repair will be faster with LIFESURE technology, with shorter road closure times. Road construction workers will also benefit from improved working conditions, because they will work with half-warm mixes (<100ºC) instead of with temperatures higher than 200ºC, and their exposure to inhalation of toxic vapour will consequently be reduced as well.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).
