Research team

Energy and Materials in Infrastructure and Buildings (EMIB)

Expertise

Impact of noise reducing measures (noise screens and low-noise road surfaces) Surface characteristics of road surfaces (noise through CPX/SPB, texture, skid resistance) Mechanical properties of surface and base asphalt layers (resistance to rutting, ravelling, stiffness and fatigue, ...) Thermal properties of asphalt mixtures, with application in asphalt solar collectors (HEAL - heat exchanging asphalt layer) Crumb Rubber Modified Bitumen and Asphalt Asphalt and bitumen recycling

Zinc-co-Sink, dual pathway for safe rubber granulate recycling. 01/01/2021 - 31/12/2022

Abstract

This project is being carried out by the University of Antwerp and VITO, and supported by the Belgian Road Research Centre (BRRC). Two possible solutions are being investigated to prevent the release of zinc from rubber granules; on the one hand by coating the rubber granules (UAntwerp) and on the other hand by trapping the released harmful components in a sorbent before they are released into the environment (VITO). The first phase of the research consists of a feasibility study into the most suitable solution for using unbound rubber granules in sonic crystals (for the Rubsonik project, led by BRRC). Possible solutions can, however, be developed further at a later stage (phase II) and can also be used for other applications of rubber granulates where environmental problems play a role. In the follow-up research, attention will also be paid to the recyclability and durability of both solutions (influence of ageing and/or exceptional weather conditions).

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Expert Group - Assessment of new Crumb Rubber proposals. 01/01/2021 - 31/12/2021

Abstract

Assessment of new Crumb rubber (CR) proposals for Green.er The aims of this project are the following: 1. A summary of the relevant legislation when using crumb rubber as a building material for Flanders, Walloon region, Brussels and the European Union; 2. A position paper on ecotoxicity regarding the possible risks of combinations of toxic substances, even when the individual contaminants are within their quality standards incorporated in legislation. The document will inform on ecotoxicological risk related to substances and mixtures, on expected changes in legislation (e.g. surface water), and methodologies related to ecotoxicological risk assessment; 3. A checklist for new applicants related to environmental concerns (leaching, VOC emissions, ecotoxicity, …); 4. Assessment of new project proposals for Greener by a group of experts, limited to the potential environmental impact.

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Sustainable foundations through in situ recycling with foamed bitumen technology (FOAM) 01/11/2020 - 30/10/2022

Abstract

In Flanders, more and more attention is being paid to sustainable road structures. For the time being, attention is often focused on the pavements. However, over the next few decades, foundations and sub-foundations of existing roads will also have to be renewed. Only this will enable us to maintain our road infrastructure, which is of primary economic and social importance, for future generations. Abroad, we are seeing more and more innovative use of materials for foundations: new material forms (e.g. geopolymers) and production technologies (e.g. emulsions, foamed bitumen). This project uses one of the most promising innovative technologies: in situ recycling of asphalt pavements into bonded foundations. With this technology, the existing asphalt will be milled either completely or partly, possibly with part of the foundation, and mixed on site with foamed bitumen and a hydraulic binder. This mixture is then compacted into a new foundation layer. In addition, two alternative binding agents are included in a comparative laboratory study: geopolymer to replace cement and emulsions to replace the foamed bitumen. Both materials are currently being researched by UAntwerpen for their applicability in foundations, in collaboration with Odisee University College. Foam technology has existed abroad for more than twenty years, but is not gaining a firm foothold on Flemish soil because of the high investment, numerous unknown factors for material selection and profitability, limited know-how and lack of real product descriptions. As a result, the potential of in situ recycling of existing foundations is severely underused. Furthermore, about 40% of the released asphalt granulate (600.000 tons) is currently used as unbound granulaes as embankment, or in bonded state with cement, while in combination with the foamed bitumen the precious bitumen of the asphalt granulate is still used, which would probably be preferable for an LCA and LCC. In view of the fact that foundations are often laid for public works, the sector considers it necessary to test this innovative step for Flemish road construction via a Tetra project.

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CRUMBit Phase 2. 01/09/2020 - 31/08/2023

Abstract

The main aim of this research is to identify the barriers preventing the use of recycled tire rubber in Belgian asphalt road surfaces and to develop market-ready solutions that can be presented to road authorities. The main expected results within the second phase of this project are the following: scaling up of the rubber modified bitumen to asphalt applications, leaching tests, analysis of the recyclability and an LCA/LCC study of rubber modified asphalt. The final work package includes the necessary follow-up steps to install the final product in one or more test tracks and finally get it approved for the Belgian market.

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Photocatalytic Asphalt Pavements for the Port of Antwerp (PAPPoA): a feasibility study (Port of the future). 01/03/2020 - 30/12/2021

Abstract

Asphalt pavements need to be able to withstand the effects of weather (i.e. UV, rain, and freeze-thaw cycles) and (heavy) traffic loading during their service life, while maintaining the necessary mechanical performance, e.g. limited rutting, fatigue resistance and water resistance, and providing comfortable and safe driving conditions in terms of the surface properties, taking into account mostly skid resistance and texture. Recently, not only investigations related to the mechanical performance or overall environmental impact of asphalt pavements are conducted, but more attention is given towards smart pavements, e.g. photocatalytic pavements. In most cases, TiO2 nanoparticles (semiconductor material) are used in the field of photocatalysis for many purposes, mostly for air and water-pollutant photocatalytic degradation, as it is effective, non-toxic, easily available and cheap. Due to the huge surface area of road pavements and its vicinity to the exhaust gases from automobiles, the photocatalytic capability is quoted as promising for air-cleaning. TiO2 is able to react under UV-light (only 3-5% of the sunlight spectrum) with pollutant gases, such as NOx and SO2, creating water-soluble nitrates and sulfates respectively, which are easily removed from the asphalt pavement by rain. It also has the potential to degrade soot, (spilled) oil and volatile organic compounds (VOC). In this project, we want i) to further investigate further the effects of traffic on the photocatalytic efficiency, ii) to determine possible effects on traffic safety (skid resistance) and iii) to develop an in-situ test setup to measure the NOx reduction.

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Purchase of a gyratory compactor for asphalt samples. 01/01/2020 - 31/12/2021

Abstract

As both present gyratory compactors are at the end of their lifespan (purchase in 2000 and 2008), with numerous calibration issues and temporary failure, a new gyratory compactor for research purposes is budgetted on this project. This device is essential as a first step in asphalt research as many standardized test methods, such as fatigue and water sensitivity, have to use specimens compacted according to EN 12697-31. With this device, cylindrical asphalt test pieces with a diameter of 100 or 150 mm are compacted, including the real-time monitoring and measurement of important research parameters such as the percentage of air voids and the shear stress. In addition, the height and apparent volumetric mass of the specimen can be checked and displayed. All necessary accessories such as molds for both standard and warm mix asphalt mixtures are included in this project proposal.

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AQ²UABIT – Advanced Qualitative and QUantitative surface Analysis of BITuminous binders using laser scanning confocal microscopy. 01/01/2020 - 31/12/2021

Abstract

In this project, an innovative methodology is developed by using Laser Scanning Confocal Microscope (LSCM) to investigate the behaviour of bituminous binders and mortar under specific physical and mechanical conditions including the impact of several additives. Bitumen, an oil derivate, is an important binder used in asphalt mixtures, roofing materials and emulsions. Regarding the circular economy, a higher recycling rate and increased service life is expected for future application, as it provides both economic and ecological benefits: a base layer with 40% reclaimed asphalt is about 25% cheaper and its total environmental impact is reduced by 6% (based on an LCA-study). An increased service life and quality avoids mobility problems, damage, fast deterioration etc. In most cases, both aspects are proven by mechanical tests in laboratory. However, efficient use of this material demands more and more scientific insight in the fundamental structural behaviour of bitumen. In order to enhance the current sustainability vision of 'closing loops', besides the mechanical properties, also the physico-chemical aspects must be taken into account, especially for higher recycling rates, fibre reinforcement, and additives improving healing and fatigue resistance. Moreover, both the development of innovative technologies, such as smart fibres in bitumen, and understanding the behaviour of the bituminous mixture, e.g. the ageing mechanism, need validated physico-chemical models. In this project, both methodologies, mechanical and physico-chemical aspects, are used to investigate the properties of the same bituminous samples (bitumen and mortar). A new technology is introduced and validated: the latest Laser Scanning Confocal Microscope (LSCM) allows for measurements across a 50 mm area with nanometre resolution (5 nm in Z-direction and 10 nm in the XY-direction). This technology allows to scan quickly (5 s measurement time) the bitumen surface in order to visualize aspects like bee structures (wax content) and bitumen coverage (adhesion between binder and granulate). Furthermore, the surface profile and film thicknesses are measured as well, which is important in the analysis of bitumen blending. Lastly, by combining these qualitative images with the Digital Image Correlation (DIC) methodology, it will be possible to obtain detailed quantitative results and to track changes in the bituminous mixture on a nanometre scale, e.g. during blending or healing. This technology will be used, together with mechanical tests (Dynamic Shear Rheometer, Direct tensile tests, Fraass bending point) to investigate the ageing/healing process, blending of old and new bitumen during recycling, and optimized use of additives, such as fibres, crumb rubber and rejuvenators. The project is divided into three steps: - integration of this new high-tech equipment, especially adjusted for bitumen research, in our bitumen laboratory, including Matlab software for data analysis; - development of a methodology for testing bituminous samples using an LSCM to fully understand bitumen morphology and physico-chemical mechanisms, related to ageing/healing, improved use of additives and as verification for mechanical tests. An opensource database of 6 binders, containing the physico-chemical and rheological properties, will be available and a secured database with the special binders will be available for collaborative research. - valorisation trajectories for designing new materials in a bituminous matrix, such as smart fibres or enhanced crumb rubber modified bitumen.

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Automated inspection of infrastructure using drones (AutoDrone) 01/10/2019 - 30/09/2021

Abstract

In this project we will use drones to detect and monitor damage in infrastructure: wind turbines, bridges, buildings, solar panels, pavements, etc. Firstly, an overview of available path planning tools will be given. Secondly, we will develop machine learning tools to automatically detect damage (cracks, potholes, corrosion). The third aim of the project is the development of a methodology to allow a systematic comparison of repeated drone based camera measurements. During the project 9 case studies will be performed. The project is performed by UAntwerpen and WTCB together with a large consortium of companies active in drone based inspections or owners of infrastructure.

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Crumb rubber modified bitumen (CRUMBit). 27/05/2019 - 30/06/2020

Abstract

The main purpose of this research is to identify the barriers which inhibit currently the use of tyre-derived crumb rubber in Belgian asphalt roads and to develop different market-ready solutions that can be introduced to the road authorities. The main expected results for phase I of this research are the following: detection of possible toxicity and health issues when using crumb rubber as bitumen modification (e.g. measurement of the volatile organic compounds or VOCs) and comparison of the mechanical and rheological properties of crumb rubber modified bitumen (CRmB) with commercial polymer modified bitumen (PmB).

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The impact of road degradation and traffic noise interventions on the quality of life. 01/04/2019 - 30/03/2020

Abstract

In a recent publication by the World Health Organisation it is recommended to keep (weighted) traffic noise levels during the whole day (Lden) below 53 dB(A) and during the night (Lnight) below 45 dB(A). As these new recommendations are stricter than the previous ones, an increase of (traffic) noise interventions can be expected in Belgium and Europe. Recent research also states that the effectiveness of traffic noise interventions on human health has been investigated in only a limited amount of studies. It is therefore important to further investigate this link. In this project, an answer to this question will be given regarding two types of noise interventions: low noise road surfaces and noise barriers. This will be achieved by combining already available results from acoustic measurements and surveys with results from detailed case-specific noise maps (Lden and Lnight), calculated in IMMI. Two test locations with so-called thin noise-reducing asphalt layers, five control streets (all streets located in Antwerp) and seven locations equipped with noise barriers (across Flanders) are part of this research. A second objective is to determine the impact of the degradation of road surfaces on environmental noise maps, by using available CPX-results as input for noise maps of a city center, and by evaluating the sound files with psycho-acoustic descriptors and in listening tests. A database with different CPX-sound files will be constructed first (differences in speed, type of pavement surface, age and number of defects …), before analysing them using the Psysound Matlab toolbox.

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Characterization of advanced materials using hybrid inverse modelling from full-field optical vibration measurements. 01/11/2015 - 31/10/2019

Abstract

Quantitative values for mechanical properties of materials are required in the simulation of the behavior of structures and systems in several engineering domains: civil engineering (buildings, bridges, roads, …), mechanical engineering (aircraft, cars, …), biomedical engineering (implants, scaffolds, etc.) and electronic engineering (semiconductor materials). In addition, the knowledge of these material properties provides a means to follow-up the health of a structure or system during operation and to estimate the remaining lifetime. The proposed novel hybrid material characterization method combines two distinct approaches to estimate mechanical material parameters, which has never been attempted before. By using laser Doppler vibrometry for the optical measurement of both resonating (at low frequencies) and propagating surface waves (at high frequencies), modal parameters and wave propagation characteristics can be derived simultaneously. By comparing these results with Finite Element and analytical models and by using an inverse modelling approach with intelligent optimization algorithms, it will be possible to identify more material parameters with an improved accuracy in a reduced measuring time. This will allow applications on more complex materials (e.g. layered poro-elastic road surface) in an in-situ environment. The proposed method will lead to several innovations, in the fields of measuring, data processing and optimization, and will be validated in three different applications: asphalt pavements (civil engineering), composite materials (mechanical engineering), and a tympanic membrane and bone material (biomedical engineering).

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Preliminary study into the economic and technical feasibillty of the use of river sludge in bitumen bound materials 07/10/2014 - 28/02/2016

Abstract

This project represents a formal research agreement between UA and on the other hand the Flemish Public Service. UA provides the Flemish Public Service research results mentioned in the title of the project under the conditions as stipulated in this contract.

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Pilot project Quiet Road Surfaces: technical guidance and implementation monitoring program. 01/09/2014 - 31/12/2017

Abstract

This project represents a formal research agreement between UA and on the other hand City of Antwerp. UA provides City of Antwerp research results mentioned in the title of the project under the conditions as stipulated in this contract.

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