A new study from Central Auckland shows pedestrian assertiveness and specific vehicle characteristics significantly influence driver-yielding behavior at mid-block sections, highlighting the importance of reducing speeds and enhancing gesture communication for safer road sharing.

Parichehr Dogani Aghcheghloo, Tam Larkin, Douglas Wilson, Glynn Holleran, Maedeh Amirpour, Tom Allen, Grant Covic

Please read the abstract for a detailed overview:


Wireless charging of Electric Vehicles (EVs) is seen as part of an important strategy to reduce emissions from essential transportation trips of people and goods. Resonant Inductive Power Transfer (IPT) is used in the development of wireless charging systems for in-road charging systems. IPT pads are embedded in a pavement infrastructure to create a magnetic field that is coupled into a similar pad fitted underneath an EV. This is then converted to the voltage and current needed to charge the onboard battery. This method enables EVs to wirelessly receive a charge while stationary or in motion. However, ensuring the robustness of this integrated in-road system is essential. Poor interface bonding between a surrounding asphalt mixture and an IPT pad decreases the structural integrity within the IPT pad-asphalt pavement system, hence increasing the risk of damage to the system. The purpose of this study is to investigate the behavior of an IPT pad-asphalt interface zone by performing direct shear tests. In the experimental setup, a normal compressive load is applied to a three-layer cylindrical specimen, comprising an asphalt mixture, the interface material, and the material forming the outer containment layer of the pad. The influence of temperature, moisture, and normal stress on the interface shear strength is investigated. Among the three interface materials tested (epoxy bitumen, epoxy resin, and structural plastic adhesive), the epoxy resin material showed the highest shear strength at 25 °C. The interface shear strength and the shear stiffness decreased for all three materials with increasing temperature, with the epoxy bitumen material being the most temperature sensitive, yielding a decrease in strength of 77 % and stiffness of 62 % between 15 °C and 40 °C. Experiments were performed using an orthogonal test design. Five variables, known to affect the interface shear strength, each variable assuming three values, were considered. The results of a range analysis and analysis of variance (ANOVA) showed that temperature has the most significant effect on the shear strength of the interface zone, i.e. between the asphalt mixture and pad surfacing. Other important factors affecting the shear strength are the interface material and the shear deformation rate. A numerical study of a full-scale IPT-asphalt pavement system is presented to show the effect of the interface bonding condition on the longitudinal and transverse strains at the bottom of the asphalt layer and the fatigue life. The results of this study will be used in the design of an IPT pad-asphalt pavement system by minimizing the differential permanent displacements between an IPT pad and the surrounding asphalt pavement.

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