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The phenomenon of hydroplaning poses a risk when landing an aircraft on a wet runway. This study developed a finite element (FE) framework comprising a dual-tyre model, water film models, a runway model, and an interaction model to investigate wet runway landings. The dual-tyre model was created with a geometric description and material properties. Water film models for even and uneven water depths were constructed based on a coupled Eulerian–Lagrangian algorithm. The runway model was obtained through surface scanning and 3D reconstruction. The interaction model was calculated using the power spectrum density and viscoelastic property of rubber. Based on the FE approach, the effect of the slip ratio on the hydroplaning phenomenon was discussed. The results indicated that hydroplaning speed generally increases with the slip ratio. Furthermore, single- and dual-tyre wet runway landings with an even water film depth were simulated, and the results revealed similar accuracy between the two landing types. Next, the study of dual-tyre landings indicated that landings in varying depths of water face the risks of hydroplaning and veering off simultaneously. The FE approach was further used to analyse dual-tyre landings on runways with a yaw angle. [ABSTRACT FROM AUTHOR]

This paper aims to explore the performance and economy of asphalt mixture with waste tire rubber (WTR)/ethylene-vinyl acetate (EVA) compound-modified asphalt. In this paper, five kinds of WTR/EVA asphalt mixture were selected as research targets, 70# base asphalt mixture and 5% styrene–butadiene–styrene (SBS) asphalt mixture were compared. Laboratory test results showed that WTR and EVA could significantly improve the performance of the asphalt mixture. The rutting resistance and anti-ageing ability of 15%WTR + 4%EVA asphalt mixture were superior to the 5% SBS asphalt mixture, and the anti-cracking ability and water stability were extremely close between them. Furthermore, the analysis of variance results revealed that WTR and EVA had a significant effect on asphalt mixture performance, the effect of EVA was more obvious than WTR. According to the economy analysis, the application of WTR/EVA-modified asphalt could significantly reduce construction costs, the material cost of 15%WTR + 4%EVA asphalt mixture was about 9.3% lower than 5% SBS asphalt mixture. As summarised above, WTR/EVA compound-modified asphalt mixture was an economical and environmentally pavement construction material due to its superior performance and lower cost, and 15%WTR + 4%EVA was the optimal combination dosage for asphalt mixture. [ABSTRACT FROM AUTHOR]

The phenomenon of hydroplaning poses a risk when landing an aircraft on a wet runway. This study developed a finite element (FE) framework comprising a dual-tyre model, water film models, a runway model, and an interaction model to investigate wet runway landings. The dual-tyre model was created with a geometric description and material properties. Water film models for even and uneven water depths were constructed based on a coupled Eulerian–Lagrangian algorithm. The runway model was obtained through surface scanning and 3D reconstruction. The interaction model was calculated using the power spectrum density and viscoelastic property of rubber. Based on the FE approach, the effect of the slip ratio on the hydroplaning phenomenon was discussed. The results indicated that hydroplaning speed generally increases with the slip ratio. Furthermore, single- and dual-tyre wet runway landings with an even water film depth were simulated, and the results revealed similar accuracy between the two landing types. Next, the study of dual-tyre landings indicated that landings in varying depths of water face the risks of hydroplaning and veering off simultaneously. The FE approach was further used to analyse dual-tyre landings on runways with a yaw angle. [ABSTRACT FROM AUTHOR]

This paper aims to explore the performance and economy of asphalt mixture with waste tire rubber (WTR)/ethylene-vinyl acetate (EVA) compound-modified asphalt. In this paper, five kinds of WTR/EVA asphalt mixture were selected as research targets, 70# base asphalt mixture and 5% styrene–butadiene–styrene (SBS) asphalt mixture were compared. Laboratory test results showed that WTR and EVA could significantly improve the performance of the asphalt mixture. The rutting resistance and anti-ageing ability of 15%WTR + 4%EVA asphalt mixture were superior to the 5% SBS asphalt mixture, and the anti-cracking ability and water stability were extremely close between them. Furthermore, the analysis of variance results revealed that WTR and EVA had a significant effect on asphalt mixture performance, the effect of EVA was more obvious than WTR. According to the economy analysis, the application of WTR/EVA-modified asphalt could significantly reduce construction costs, the material cost of 15%WTR + 4%EVA asphalt mixture was about 9.3% lower than 5% SBS asphalt mixture. As summarised above, WTR/EVA compound-modified asphalt mixture was an economical and environmentally pavement construction material due to its superior performance and lower cost, and 15%WTR + 4%EVA was the optimal combination dosage for asphalt mixture. [ABSTRACT FROM AUTHOR]

In the current research, effort has been made to gain a deeper understanding regarding the parameters affecting the dynamic behaviour of a sandy soil reinforced by Waste Tire Textile Fibres (WTTFs) that are produced during the recycling process of the End of Life Tires (ELTs). Such parameters as loading duration, rest time, and aspect ratio of fibres have been investigated by cyclic triaxial tests considering 3 different confining pressures and 21 different Cyclic Stress Ratio (CSR) levels. It is concluded that the aspect ratio of the fibres is a more prominent parameter than loading state and fibres with an optimum aspect ratio of 37.5 can improve the dynamic characteristics of the soil reinforced by WTTFs. Generally, the influences of fibre aspect ratio and loading characteristics on resilient modulus, damping ratio and phase angle of the reinforced specimens are diminished as CSR increases, while the permanent strain and energy absorption capability are directly related to the CSR. [ABSTRACT FROM AUTHOR]

In order to further explore the performance of mixture with waste tire rubber (WTR) and amorphous poly alpha olefin (APAO) modified asphalt, the 12%WTR+4%APAO and 15%WTR+4%APAO modified asphalt mixtures were selected as research objectives. The asphalt mixtures with matrix asphalt, WTR modified asphalt, and SBS modified asphalt were prepared for comparative analysis. Through the mixture design, the optimum asphalt-aggregate ratio of five asphalt mixtures was determined respectively. The volumetric parameters and resilient modulus were studied. The laboratory performances were studied by standard Marshall stability test, wheel tracking test, immersion Marshall test, freeze–thaw splitting test, indirect tensile strength test, indirect tensile fatigue test, and Marshall stability after long-term aging test. Compared with the other three asphalt mixtures, the results showed that the 12% WTR+4%APAO modified asphalt mixture had the highest Marshall stability and high-temperature performance. While the 15% WTR+4%APAO modified asphalt mixture had better permanent deformation resistance at high temperatures, moisture stability, aging resistance, and relatively good fatigue performance. The statistical hypothesis test results also confirmed that WTR/APAO modified asphalt has a significant effect on mechanical properties. Based on the results of various performance, the 15% WTR+4% APAO was the optimal content for asphalt mixture. [ABSTRACT FROM AUTHOR]

Waste tire rubber has been incorporated into asphalt modification for decades due to its various benefits. There are two main mechanisms during bitumen–rubber interaction: rubber swelling and chemical degradation. This study surveys these two processes from the viewpoint of polymer science. The kinetics of rubber dissolution and thermodynamics of rubber swelling are discussed to provide a fundamental understanding of the interaction process and to demonstrate how optimisation of material selection and processing procedures can lead to the desired binder properties. Factors including the interaction conditions and raw material characteristics are analysed based on the previous theories and compared with experimental results. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to develop a series of artificial neural network (ANN) models to predict the viscosity values of crumb rubber-modified (CRM) binders using four input variables: asphalt binder source, rubber size, mixing duration and rubber content. The results indicated that ANN-based models are effective in predicting the viscosity values of CRM binders regardless of rubber type and can easily be implemented in a spreadsheet. In addition, the developed ANN model can be used to predict viscosity values of other types of CRM binders. Furthermore, the results also show that asphalt binder source, rubber size and rubber content are the most important factors in the developed ANN models while the mixing duration is relatively unimportant. The sensitivity analysis of input variables indicated that the viscosity changes significantly with changes in asphalt binder source, rubber size and rubber content. [ABSTRACT FROM AUTHOR]