Demonstrating Innovative Technologies for the Flemish Asphalt Sector in the CyPaTs Project

Abstract

In 2015, the ROAD_IT project initiated the development and demonstration of an integrated and coherent IT process control system for the Flemish asphalt sector in order to modernize existing asphalt paving technologies and to obtain real-time data to monitor pavement behavior. One of the demonstration test tracks is CyPaTs, the construction of a bicycle path built in September 2017, using innovative technologies (www.uantwerpen.be/cypats). Five technologies are described in this contribution. An asphalt solar collector (PSC) with a piping system was installed directly in the asphalt. Cold water during summer season and hot water in winter season running through the pipes, keep the asphalt structure in a better temperature interval, avoiding rutting and cracking. Other advantages of this system are: energy gain, the prevention of damage to asphalt and the enhancement of traffic safety. The expected energy gain per year varies between 0.5 and 0.8 GJ/m2. About 20% of this energy is used for the operation of the asphalt collector itself. The remaining 80% can be used in nearby buildings. Fiber Bragg Grating (FBG) monitoring system was integrated in all three asphalt layers for the first time in Belgium. Two novel approaches of FBGs installation in asphalt layers were elaborated in this bicycle path: installation of FBGs in prefabricated asphalt specimens at the bottom of base layer and installation of FBGs in a saw cut of approx. 2mm in the previously constructed asphalt layer. The results proved a survival rate of the FBGs of 100%. The obtained strain and temperature data from FBG monitoring system has proved to be an excellent approach to establish and reflect the real condition of the asphalt pavement behaviour in time at different temperatures. The temperatures of the asphalt pavement during construction were followed up by the infrared thermography measurement techniques: a thermographic line-scanner (PAVE-IR by Moba AG) which was mounted at the back of the finisher and a hand-held IR camera (FLIR T640) was used for taking pictures every 2 meters. A real-time temperature contour plot of the pavement during construction was created to monitor asphalt pavement temperatures for quality inspection during the paving process or for later assessment. Two other non-destructive technologies for quality assessment were applied during this project. At first, the thickness was measured using aluminium plates and the MIT-SCAN T3. The obtained values were compared with topographic height measurements. Secondly, the density was measured with the PQI-380 non-nuclear density meter at several spots. The objective here is to check the density of the bicycle path, as well as the accuracy and investigate different parameters that influence the variations of the results, in particular the temperature dependency.