The use of treated aggregates in pavements to reduce the challenges of snow and ice in winter time

Project facts

Project promoter
Complutense University of Madrid
Project Number:
ES07-0068
Target groups
Researchers or scientists
Status:
Completed
Initial project cost:
€23,320
Final project cost:
€22,644
From EEA Grants:
€ 22,644
The project is carried out in:
Spain

Description

Several de-icing chemicals are used to reduce the ice formed in roads in winter. The most common are chlorides-based salts like NaCI or MgCI which are spread directly over the roads. This method is efficient and inexpensive but produces corrosion to metal in vehicles or impacts on water quality, soil and vegetation. The aim of this project is try to find types of aggregates that could absorb and releasing anti-icing chemicals in pavements. The main idea is to analyse the absorption capacity of different stone aggregates and evaluate the decrease of the bond between snow/ice and the pavement. The donor partner, Norwegian University of Science and Technology, has experience in technology, construction and winter maintenance of roads. The researcher from the project promoter, Complutense University of Madrid, has focused her studies on road aggregates behaviour under winter conditions, analysing how these conditions affect the main properties of these materials and their long term use. The planned cooperation will benefit both partners as an entirely new collaboration will be set up, combining the specific expertise of the institutions and researchers involved.

Summary of project results

Several de-icing chemicals are used to reduce the ice formed in roads in winter. The most common are chlorides-based salts like NaCI or MgCI which are spread directly over the roads. This method is efficient and inexpensive but produces corrosion to metal in vehicles or impacts on water quality, soil and vegetation. The project has helped to better understand the interaction between asphalts pavements and snow and ice. The work has been focused on the study of stone aggregates, which are the main components of road asphalts. The results obtained can help to use friendly environmental materials on pavements and to reduce the use of chemical compounds during winter season on roads. It is well known that these chemical products cause a negative impact on the environment close to the road and comprises, damages on road pavements and structures or corrosion of motor vehicles. For these reasons, a good knowledge about snow/ice adhesion, and thus, the reduction of the use of salts on roads, is economically and environmentally important to Road Administrations. During the project, two common types of rocks used as aggregates on roads were studied in laboratory. The effect of the roughness and chemical composition on ice adhesion was evaluated and the results showed that ice bonding increases when surface roughness increases, regardless the chemical composition of the stone. Additionally, the ice adhesion to a rock used as agtgregates on roads when it is wetted by a NaCI solution was also studied in laboratory. The amount of solution was prepared in base of the equilibrium curve of NaCI+H2O system, taking the minimum effective NaCI amount to a determined temperature. The results obtained showed that the ice adhesion to the rock is lower near to equilibrium temperature. Data obtained during the project were collected at the Ice Laboratory of the Department of Civil and Transport Engineering at NTNU and at the Petrophysics Laboratory belonging of the Geosciences Institute IGEO. The main beneficiaries of this projete will be researchers and Road Administrations. It has helped to find types of rocks which can make easier the snow removal during winter and thus, to reduce the use of chemical deicers and anti-icers on asphalt pavements. On the other hand, a better knowledge of ice and snow disbanding by the effect of salt solutions can also help to reduce the amount of chemicals used on roads during winter maintenance practices.

Summary of bilateral results

The donor partner, Norwegian University of Science and Technology, has experience in technology, construction and winter maintenance of roads. The researcher from the project promoter, Complutense University of Madrid, has focused her studies on road aggregates behaviour under winter conditions, analysing how these conditions affect the main properties of these materials and their long term use. Both partners have worked and shared results and knowledge and such results shall be published in a joint scientific paper. The project and its results may help to open new studies and collaborations between Faculties of Geology Sciences and Civil Engineering at Complutense University of Madrid and Norwegian University of Science and Technology.