Numerical and experimental development of an “Accelerated Repeated Rolling Wheel Load Simulator” (ARROWS)

• Applicants: Professor Dr.-Ing. Michael Kaliske; Professor Dr.-Ing. Markus Oeser
• Subject Area: Applied Mechanics, Statics and Dynamics ; Architecture, Building and Construction History, Construction Research, Sustainable Building Technology ; Structural Engineering, Building Informatics and Construction Operation
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 414936990

In the mechanistic design of flexible pavements under consideration of moving loads, particular attention is paid to achieving a realistic description of fatigue phenomena in asphalt layers due to tensile stresses. If the resulting external loading exceeds the fatigue resistance of the asphalt, fatigue cracking occurs. The initiation of micro and macro cracks is highly temperature dependant as well as stress dependant. However, current experimental setups exhibit stress states and mechanisms of crack propagation that differ strongly from those present in real pavements. Numerical approaches are limited to a reproduction and depiction of single components of the underlying phenomena or generally require further development to allow for applicable results. Therefore, the proposed research project a numerical-experimental approach and a realistic reproduction of loading conditions of asphalt layers under moving loads are pursued. The numerical and experimental development of an “Accelerated Repeated Rolling Wheel Load Simulator” (ARROWS) represents the core of the research project and aims to allow for accurate knowledge on the service life as well as the fatigue susceptibility of pavement structures with asphalt layers. The focus is on realising a realistic depiction of crack formation and crack propagation under real loading scenarios including magnitude, loading velocity and loading progressions.In the initial phase of the joint research project a numerical validation (simulation of the loading conditions from stationary tyre passes and due to the developed ARROWS testing device) shall be provided and the respective loading conditions are to be compared with one another. Simultaneously, the numerical conception of the testing device is carried out (design details, operative stability). Furthermore, the experimental conception of the device will be further developed. The focus of the research project is the experimental characterisation and the numerical representation of damage and healing phenomena of asphalt mixtures in pavements under moving loads. Based on this, a numerical model shall be developed to allow for long term predictions with a large number of loading cycles and long test durations. Experiments are conducted to identify the model parameters for a precise description of short-term and long-term behaviour of asphalt (material and structure). Initial structural tests allow for an evaluation of the prediction quality of the selected simulation approach for long-term behaviour; this is based on real-time accelerated testing by means of the construction of a scaled ARROWS device. Finally, the attained insight will be inspected with regard to transferability of assumptions to an unscaled, full-sized ARROWS device.

• DFG Programme: Research Grants