Publicaties

  • 16 augustus 2015

    THE ASPHALT CONSTRUCTION SITE OF THE FUTURE – A DUTCH PERSPECTIVE

    Onderwerp Asfalt
    Auteur(s) F. Bijleveld
    Gepubliceerd Conference on Asphalt Pavements for Southern Africa (CAPSA)
    Omschrijving This paper brings together challenges facing asphalt construction in the Netherlands and the vision for a Construction Site of the Future given ever-changing requirements of the road construction industry. Drawing on the experiences of more than 40 case studies monitored over a period of eight years, this paper highlights a few key issues relating to process improvement and how it can be addressed using current construction informatics. The vision is firstly communicated to professionals using a scenario for the asphalt Construction Site of the Future. The scenario is intended to highlight the potential benefits of integrating new sensor technologies and informatics into the rather complex asphalt construction process. Current practical challenges are then addressed including the development and integration of real-time information systems to support the process in the context of operational, tactical and strategic decision-making. We highlight the developmental implications for the construction industry should the vision for the future be adopted, the potential benefits of implementing new sensor technologies and informatics, the effects on human resources, and the potential impact on knowledge management initiatives. Finally, we position the important roles of public clients and contractors to successfully address challenges of variability in the asphalt construction process.

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  • 01 februari 2015

    Aligning laboratory and field compaction practices for asphalt – the influence of compaction temperature on mechanical properties

    Onderwerp Asfalt
    Auteur(s) F.R. Bijlevelda, S.R. Millera, A.H. de Bondt & A.G. Dorée
    Gepubliceerd Taylor & Francis
    Omschrijving The approach used to identify a compaction temperature in the laboratory, based on binder viscosity, provides a single compaction temperature whereas, on-site, a roller operates within a temperature window. The effect on the density and mechanical properties of rolling during a temperature window remains unclear. Consequently, asphalt concrete binder mixtures were compacted in different temperature windows in the laboratory using a Roller Sector Compactor, and the observed phenomena were then related to field study observations. The results show that while similar densities can be achieved in a broad range of temperature windows, other mechanical properties such as fracture energy may decline up to 30% if compacted outside the optimum temperature window. These results indicate that a compaction temperature window should form part of mix design and quality control. The paper proposes specifying a compaction window based on temperatures and the resulting mechanical properties rather than a single compaction temperature.

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