Search

• The mechanism of rolling resistance of asphalt pavements is presented. • The measuring and modelling approaches of rolling resistance are summarised. • The prediction methods of fuel consumption and environmental impact are reviewed. In the context of climate change and global warming, the attention on the environmental cost of pavements is increasing. To scientifically quantify the environmental cost of pavements, accurate prediction of rolling resistance and fuel consumption is important. In this paper, a comprehensive review on rolling resistance of asphalt pavements and its environmental impact was presented. At first, the commonly used definitions of rolling resistance and texture characterisation methods of pavement surface were introduced. Then, the influence of different factors on rolling resistance was discussed. Next, the measuring and modelling approaches of rolling resistance were reviewed. At last, methods which can be used to predict fuel consumption and environmental impact were presented. It was found that an ideal approach for texture characterisation of pavement surface is to make use of the entire wavelength spectrum of road profiles and consider the enveloping curve of tire treads. Furthermore, the fact that rolling resistance can be influenced by different factors introduces difficulties in accurate measurement and modelling of rolling resistance. Moreover, testing methods and conditions have a significant effect on the empirical modelling of rolling resistance, while it is difficult and time-consuming to consider all the energy loss in the computational modelling of rolling resistance. In addition, the prediction of fuel consumption and environmental impact highly depends on the formulating methods and measuring conditions. The work presented in this paper will help to gain more insight into rolling resistance and its environmental impact, which ultimately promotes the construction of environmentally friendly pavements. [ABSTRACT FROM AUTHOR]

Excessive loading conditions and internal heat build-up are the major causes of failures in solid resilient tires. Both operational and design related factors can affect tire performance including internal stress generation and heat build-up. In spite of their limitations, experimental techniques are still the most common method of identifying the factors that affect tire performance. This study explores a combined approach of numerical modelling and Design of Experiments (DoE) to identify the impact of several key design and operational factors on the performance of solid tires under different temperature levels. First, 3D Finite Element (FE) static and thermal models of the solid resilient tires are developed by incorporating suitable temperature dependent hyperelastic material models and relaxation properties. The temperature-dependent mechanical behaviours of rubber material are obtained by using Dynamic Mechanical Analyzer (DMA) and the William Landel Ferry (WLF) parameters. The developed FE thermal model is used to predict the tire performance, including the tire blasting region, which is then validated with experimental data. Secondly, a two-level fractional factorial DoE analysis is developed using response readings of maximum stresses, deformations and contact pressure obtained from the validated FE thermal model. The factors used in the DoE include the number of rubber layers, applied load, rolling speed, ramp angle and aperture level. The results provide optimal operational and design parameters of the solid resilient tire at different environmental temperatures and show the potential for considerable stress reduction with minimal changes to tire deformation and contact area. These results highlight the capability of the combined FEM and statistical design approach to drastically reduce the number of physical experiments required for obtaining optimal tire performance thus saving significant time and cost. • A DoE-FEM methodology is introduced to enhance the performance of solid tires. • Developed Thermo-mechanical FE model shows good agreement with experimental data. • Obtained DoE responses at different temperatures using thermo-mechanical model. • Optimum factor levels were identified under operating states of the tire. [ABSTRACT FROM AUTHOR]

• Detailed finite element models of solid tires for static and dynamic analyses. • Curve fitting and accuracy measures used to select suitable hyperelastic models. • 3D model validation with experimental data shows very good agreement. • Inclusion of elliptical cavities greatly reduces heat build-up and sidewall cracks. Solid tires are often utilized to bear excessive loads. Therefore, sidewall cracks and internal heat build-up affect their durability more significantly. It is a challenge to minimize these factors and improve tire performance while maintaining the functionality of the solid tire. Moreover, there are no specific standard guidelines for modifying the solid tire design to achieve this objective. This study proposes several design and performance improvements to the solid resilient tire and investigates the performance of these modified designs using the Finite Element (FE) method under static and dynamic conditions. For these FE simulations, suitable hyperelastic models are obtained using curve fitting combined with three standard error measures. The results show that the Mooney-Rivlin, Ogden, and Yeoh material models show good agreement with experimental data for modelling the base, cushion, and tread layers of the tire, respectively. The developed FE models are validated using experimental data obtained from a leading tire manufacturing company in Sri Lanka. The validated model is used to develop and analyse two distinct tire models which have two different cavity geometries (circular and elliptical) in their cushion layers to minimize heat build-up and sidewall cracks. The tire reinforcements are also rearranged to further improve the performance of the models. The introduction of cavities helps to reduce strain energy dissipation and to increase the dissipation of internal heat by convection. Furthermore, the stress intensity on the side walls is also reduced, thereby minimizing sidewall cracks. Numerical experiments show that the modified designs have a lower strain energy density, lower stress concentration, and less material utilization when compared to the basic tire design. [ABSTRACT FROM AUTHOR]