Activities update at March 2018
THE FIRST LOW-NOISE EMISSION ROAD SURFACES FOR THE PROJECT NEREIDE HAVE BEEN COMPLETED
FROM ELT RECYCLED RUBBER POWDER TO ASPHALT MILLINGS, THE NEW PAVEMENTS PRODUCED AND LAID WITH “WARM” TECHNOLOGY REDUCE THE EMISSIONS OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) BY 30%.
Coordinated by the Department of Civil and Industrial Engineering of the University of Pisa in collaboration with ARPA Tuscany, BRRC-Belgian Road Research Centre, Ecopneus, IDASC-CNR the Institute of Acoustics and Sensoristics “Orso Mario Corbino” and Region Tuscany, the Project LIFE Nereide (Noise Efficiently REduced by RecycleD pavEments) was born with the main objective to contribute to the resolution of the environmental issues linked to the disturbance phenomena created by vehicle noise. This problem is particularly felt in urban areas and it is strictly dependent on the characteristics of the flooring surface. To this aim, the project wants to define some guidelines for the planning, construction and monitoring of two experimental sites, created using 12 bitumen conglomerate mixes for wear layers at low sound emissions. Such mixes will be produced at lower temperatures than the ones of the traditional hot conglomerates, using the so-called “warm” technologies. They will be composed of not only new aggregate and
The key eco-objectives the project Nereide wants to achieve are, thus:
• noise pollution mitigation;
• reduction of CO2 emissions into the atmosphere, thanks to the lowering of the processing temperatures and the reuse of waste materials, that would otherwise be destined to the landfill.
For the drafting of the guidelines that will contain useful information for the identification of technologies, materials and typologies of intervention to adopt, without prejudice to the mechanical performance and the levels of
The laying of the new surfaces is planned in two moments, with a one-year gap in between, respectively: in autumn 2017 and 2018.
In addition to the experimental stretches in bitumen conglomerate, the experimentation of a porous-elastic flooring, PERS (PoroElastic Road Surface), is planned first in Belgium and then in Italy in summer 2018. With this type of surface, it will be possible to reuse greater percentages of rubber from ELTs. After a year from the beginning of the project and planning to start road resurfacing with the mixes containing rubber powder by the end of autumn 2017, the following activities have been carried out.
The individuation of the experimental sites
The urban road stretches subject of intervention have been chosen based on a priority index linked to the contemporary presence of several schools and of over 800 people exposed to daily noise levels higher than 65 dB(A). The first experimental site of about 2,400 metres has been identified on the “S.R.T. 439 Sarzanese-Valdera” in the town of Massarosa (LU).
The project of the experimental mixes and the Life Cycle Assessment
The design of the mixes represents, without any doubt, the most important task of the project. An in-depth knowledge of the materials, of the volumetric composition and of the mechanical characteristics of the thickened mix is fundamental to be able to predict its behaviour once installed.
A revision of the existing technologies has been carried out. Its aim was the definition of the maximum quantities of recycled materials (rubber powder and asphalt millings) that may be used in the mixes. It was also necessary for the identification of additives or specific technologies used for the reduction of the temperature for the laying of the modified asphalts. After such revision activities, the design of the mixes planned for the first period of installation was developed in the laboratory.
In detail, the mixes are:
• Two “traditional” hot control mixes;
• A draining mix 0-12;
• a Splittmastix Asphalt (SMA) 0-12 mix;
• four innovative “warm” mixes, containing rubber powder with uneven aggregate gradation, of which: two with
In order to identify and be able to quantify the material and energy consumption as well as the emissions released into the environment associated to the life cycle of the proposed experimental surfaces, a careful Life Cycle Assessment (LCA) was also carried out. It compared all possible combinations of wear courses containing asphalt millings, rubber powder and produced with warm technology with a traditional hot asphalt mixture, taken as
The results obtained from the comparative LCA have shown that the combined effect of the mixes with warm technology and the use of recycled materials reduce noticeably the environmental costs associated to the processes of road surfacing and maintenance of the wear courses. It, thus, represents a valid alternative to traditional technologies. It also fully meets the “eco-environmental” requisites expected from this new technology. In particular, the use of these recycled materials allows, above all with reference to asphalt millings, noticeable savings of raw materials such as bitumen and aggregates. Moreover, the technology of Warm Mix
Alongside laboratory testing, some ante-
The aim is to be able to quantify the benefits obtained following a “before-after” approach.
Structural surveys and surface characteristics
The survey of the structural characteristics was carried out with a Falling Weight Deflectometer (FWD) equipped with a Ground Penetrating Radar (GPR) for the constant detection of the existing surface thickness. Due to the construction inhomogeneity of the inspected surface, the usual procedures for the structural surface analyses are, in general, not very reliable. Indeed, S.R.T. 439 “Sarzanese-Valdera” falls within those roads of ordinary viability based on ancient historical roads. These are characterised by the presence of an intermediate layer, placed on the subbase made with natural stones of variable thickness, and by thin bitumen conglomerate layers. The usual analysis procedures (using
The evaluation of the surface characteristics was made with reference to macrotexture and grip. The texture was detected by the means of a mobile laser profilometer. Based on the obtained results, the macrotexture was calculated with reference to ETD. The grip measurements, carried out with a Skiddometer BV11, were expressed in terms of BPN, CAT and F60 (according to IFI’s model). Such indicators fall within the Life Performance Indicators (LPI). These represent the monitoring indexes of the impacts of the project.
Noise survey and measurement protocols
The acoustic performances have been evaluated by ARPAT (the Environmental Protection Body of Region Tuscany) and by CNR-IDASC (Institute of Acoustics and Sensoristics “Orso Mario Corbino”)
with reference to tyre-road noise, with Close Proximity Index (CPX) and Standard Pass-By (SPB) methods. The sound absorption was measured with the Adrienne Method.
The noise levels of the psychoacoustic indicators, obtained thanks to the Close Proximity Index (CPX) method, have been calculated for every single stretch of road where the experimental mixes will be laid, bearing in mind the specific stretch of road (different traffic fluxes and speed), the orography and other specific elements, such as the presence of noisy activities. Alongside the standard
Alongside the monitoring, ARPAT and IDASC are developing measurement protocols in addition to the standard ones provided for by the Legislation that would allow a better estimate of the influence of each type of flooring on sound emissions.
In particular, ARPAT has prepared a protocol that can derive the SBP indicators as defined by the Rules and Regulations by the means of normal fixed control units of noise control and a simple traffic counter, but without the need of manned measurements. Such protocol provides for the use of SEL devices instead of the LAmax. This is in line with the Harmonoise Project, which, once validated, will make it possible to estimate the disturbance of every single vehicular category, thus facilitating mobility policies. IDASC is developing a system whose objective is the improvement of the measurement methods of noise absorption in situ, using pressure-speed waves mounted on board of a vehicle, instead of a microphone, for the measurement of the reflected wave - as provided for by the Adrienne Method. The new measurement protocol will be confronted with the regulated method (Adrienne) and will be validated on the new surfaces of the project.
At the same time, the ante-
Progress at may 2017
Summary of UNIVERSITA’ DI PISA – DICI activities
In this first phase of the project, the activities of the Department of Civil and Industrial Engineering at the University of Pisa consisted of a preliminary analysis and review of the state of the art of existing techniques for the detection of the highest amounts of recycled materials (recycled asphalt pavements and crumb rubber from End-of-Life tyres) and specific additives and technologies used to reduce the temperatures of set-up and realization. On the basis of this and on the results obtained from a preliminary study of the constituent materials, the design mix was conducted in laboratory to develop technical specifications for the new types of low noise emission mixtures containing recycled rubber (CRM) and produced with the "warm" technology, forecast in the first stretch campaign.
In order to assess the degree of environmental sustainability of the proposed experimental pavements, a thorough Life Cycle Assessment (LCA) study was conducted on all possible combinations of wear layers containing recycled asphalt and recycled rubber, produced with warm technology; this LCA was compared with a gap layer wrapped at hot temperature, as a reference; this procedure of analysis made possible to evaluate the environmental burdens associated with each type of mixture in terms of material, energy consumption and emissions, providing results that fully satisfy the "green” objectives expected.
At the same time, on the stretched sections of the SRT 439 Sarzanese-Valdera in Massarosa (LU), where the first experimental realization was planned in the fall of 2017, were performed measurement of lift with a Falling Weight Deflectometer (FWD) equipment and carried out a continuous evaluation of pavement thickness with Ground Penetrating Radar (GPR) equipment.
The processing of the acquired data made possible to determine the criterions of the constituent layers of the package and therefore to assess the remaining useful life of the existing pavement and the increase in expected life as a result of the realizations of the new layers.
Summary of ARPAT activities
Then a selection of acoustical methods and indicators have been carried out to define methodologies for ante and post
In combination with
ARPAT is also
In the next 3 months, analysis of urban pass by will be finalized and method is going to be validated before the end of 2017. Ante-
ARPAT has also acquired together with CNR population data from
Summary of ECOPNEUS activities
Ecopneus coordinate the design and implementation of communication materials to support project activities. The LIFE Nereide website will serve throughout the duration of the project as a constant point of reference for partners and potential stakeholders, as well as an up-to-date source of information about project objectives, initiatives and progress. The site contains all the key information about the project, planned actions, expected goals, partners and their roles.
Have been realized also a Papers Notice Board, which contain the main
Other communication tools are been planned and realized, to maximize the dissemination of
Thanks to dedicated press activities carried out by Ecopneus on a selection of journalist interested to the topic and to other dissemination activities carried out by the other partners, over 100 articles
During the Asphaltica Fair, the most important national event on
Over 70 people (including representatives of the Public Administration, decision makers, academics and companies of the sector) attended
A further opportunity for networking was held in July during a conference dedicated to the LIFE ReFibre project (which aims to obtain extremely durable pavements thanks to the use of recycled materials), during which a session was dedicated to the Nereide project.
Other actions will be implemented to support the advancements of project activities.