Damage caused by freeze-thaw cycles and snowploughing operations is among the major distresses affecting chip seal pavements in cold regions, with limited information regarding the behaviour of full or partial rubberised chip seal from scrap tyres. In this study, the aggregate retention performance of conventional and rubberised chip seals was evaluated under laboratory and field snowploughing conditions, as well as under 50 freeze-thaw cycles in the presence of deicing salt, followed by simulated traffic loading. The results indicated superior performance for rubberised chip seals under snowploughing operation due to the hysteresis character of crumb rubber particles against the imposed loads. Freeze-thaw and deicing results showed that mineral aggregates with high water absorption and low toughness were more susceptible to freeze-thaw damage. Although rubberised chip seal also showed sensitivity to freeze-thaw conditioning, its performance after conditioning remained comparable to that of conventional chip seal under simulated traffic loading.

To alleviate reliance on unsustainable Trinidad Lake Asphalt (TLA), a novel epoxy-modified MA binder was developed as a substitute for conventional binders. This study evaluated the impacts of curing temperature and duration on the multi-scale microstructural evolution and physicochemical properties of the binder and mixture. FTIR, LSCM, viscometry, and mechanical testing were deployed. Results demonstrate an exponential increase in curing degree over time. Both binder viscosity and phase morphology stabilized after 120 min, achieving a highly uniform polymer dispersion (average particle size: 0.2–0.3 µm) and lowered temperature susceptibility. At the mixture level, elevated curing temperatures enhanced the stiffness modulus and fatigue life but compromised permanent deformation resistance. This performance difference stems from temperature-induced epoxy particle refinement, which alters internal lubrication and healing mechanisms. The developed binder offers a sustainable, high-performance alternative to conventional TLA-MA systems.

Quantitative understanding of tensile mobilisation and stress redistribution in geocoir systems remains limited despite increasing interest in sustainable alternatives. This study presents an integrated experimental-numerical investigation of geocoir cell-reinforced sand subgrades under monotonic loading. Laboratory plate load tests were performed for two pocket sizes of geocoir cell (210 × 210 mm and 300 × 300 mm), and validated three-dimensional finite element simulations were used to quantify stress redistribution and tensile force mobilisation within the honeycomb structure. The 210 × 210 mm configuration achieved a 2.8-fold enhancement in bearing capacity and an 86% decrease in settlement relative to the unreinforced subgrade. Numerical analyses reveal pronounced stress attenuation beneath the reinforced layer and tensile force concentration near stitching regions of geocoir cells, with peak mobilisation ranging from 56% to 79% of the ultimate tensile capacity, indicating efficient structural utilisation without rupture. Prototype-scale modelling confirmed scale-consistent behaviour (<10% variation), demonstrating that soil-cell interactions, rather than boundary effects, govern confinement and tensile mobilisation.

This study investigates the effects of hydrophobic and hydrophilic nano-alumina on the durability and low-temperature performance of asphalt mixtures. Asphalt binders (50–70 penetration grade and 4.5% SBS-modified) were modified with 2% and 5% nano-alumina and tested for binder properties (penetration, softening point, kinematic and dynamic viscosity, ductility, DMA for Tg) and mixture properties (Marshall stability, moisture susceptibility, low-temperature IDT at 0°C and −20°C). No single concentration universally optimises all properties; however, hydrophilic nano-alumina (HPi) generally enhanced moisture resistance and long-term Marshall stability, while hydrophobic (HPb) improved unaged softening point. Low-temperature performance improved for 50–70 but degraded for SBS-modified mixtures. Aging dominated long-term behaviour, often overshadowing nano benefits. These findings highlight that the effectiveness of nano-alumina modification depends on the asphalt binder type, nano-alumina surface chemistry, and aging conditions, necessitating a performance-based selection approach.

This study examined a waterproofing layer composed of organosilicon hydrophobic material to inhibit capillary water rise in subgrades. The infiltration behaviour of the hydrophobic solution and its impact on the evolution of water barrier performance were systematically investigated. A viscosity–temperature model was established to analyze infiltration depth, while permeation tests on layered soils revealed the permeability of the waterproofing layer. A water–seepage attenuation coefficient was introduced to quantify the layer’s water barrier performance and its evolution. Results indicate that infiltration depth is jointly controlled by solution viscosity, temperature, and initial soil moisture content. The permeation coefficient is primarily affected by the interaction between infiltration depth and the permeation coefficient of the layered soil. Under continuous seepage, the permeability remains essentially stable. Higher water–seepage attenuation coefficients correspond to stronger water barrier performance; they are constrained by initial moisture and increase with greater hydrophobic material amounts, eventually stabilising.

Accurately determining the frequency response of asphalt pavement under vehicle live loading and thereby selecting an appropriate mixture modulus is crucial for improving the accuracy of calculating the pavement's mechanical response. This paper obtained the period of the vehicle load applied on the RIOHTRACK full-scale ring road by fitting the ring road's measured stress versus loading time data through a sinusoidal function, then presented the ring road's frequency response according to the conversion relationship between frequency and period and finally investigated the statistical relationship between frequency and depth as well as temperature, meanwhile presenting a model to predict the pavement's frequency under various depths and temperatures. The findings of this paper provide significant support for selecting an appropriate modulus parameter for asphalt pavement mechanical response calculation and will enhance the analytical level of pavement response calculation.

Accurate pavement structural evaluation using falling weight deflectometer (FWD) testing is strongly affected by pavement temperature, yet field tests cannot cover the full range of thermal conditions. This study integrates field FWD data with a parametric finite element (FE) model to examine temperature-dependent responses of full-depth asphalt pavements. A refined pavement temperature gradient model was used to generate realistic thermal profiles and evaluate the effects of asphalt layer thickness and subgrade stiffness on deflections. Results show that temperature effects are greatest near the load center and diminish with distance. Thinner asphalt layers and weaker subgrades exhibit higher temperature sensitivity, whereas thicker asphalt layers and stiffer subgrades reduce temperature-induced deflection through insulation, load distribution, and enhanced structural support. Among the evaluated deflection basin parameters, the proposed Asphalt Curvature Index (ACI) and Subgrade Curvature Index (SubCI) are particularly sensitive to temperature. These findings support improved temperature correction for FWD-based pavement assessment.

Reclaimed Asphalt Pavement (RAP) is increasingly used in new asphalt mixtures to reduce environmental impacts, but effective blending of aged binder remains challenging due to RAP’s thermal behaviour. This study develops a methodology to quantify RAP thermal conductivity using finite element modelling (FEM) validated by laboratory tests. Bulk thermal conductivity of RAP particles and aged binder was measured through parallel-plate heating, and a three-dimensional ANSYS FEM model was developed to back-calculate particle and binder conductivities. By assuming spherical particles in cubic packing and varying binder film thickness, the model produced binder thermal conductivities consistent with laboratory results (∼0.17 W/m·K). Predictions were further validated with the Generalised Self-Consistent Model (GSCM), which also estimated film thicknesses across particle sizes. Results show that thermal conductivity increases with density, decreases with air void content, and is higher for larger particles.

Inductive charging pavements for electric vehicles are limited by pavement electromagnetic properties. This study develops a magnetised asphalt mixture (MAM) using recycled Ni–Zn ferrite as fine-aggregate replacement and evaluates its performance in an 85.5 kHz S–S compensated wireless power transfer system from experiments and simulations. Ferrite incorporation increases effective relative permeability (μ eff) up to ∼21.84, while efficiency saturates around μ eff ≈ 13. A minimum MAM thickness is required for net efficiency gain across studied gaps, with a maximum gain of ∼10.4% over a conventional mixture. Under lateral misalignment (i.e. horizontal offset between the transmitter and receiver coil centres, DS = 60 mm), MAM mitigates efficiency loss, increasing coupling coefficient and efficiency by ∼0.06 and 2.4%. A permeability window μ eff ≈ 7–13 is recommended, and a 1 km WPT lane can reduce annual input energy by ∼2.3 × 104 kWh and CO2 emissions by ∼10 tons.

High-altitude and high-latitude pavements suffer simultaneous intense UV radiation and low temperatures, accelerating asphalt photo-oxidative aging and low-temperature cracking. This work explores aging mechanisms and cryogenic performance of 10%/15%/20% crumb rubber modified asphalt (CRMA) with 40/80-mesh rubber under radiation-low temperature coupled aging, plus RTFO, PAV and ozone aging. BBR tests from −6 to −24 °C characterize low-temperature rheology; SARA, GPC and FTIR capture microchemical changes. Coupled aging raises creep stiffness S, reduces m-value, consumes light fractions, accumulates heavy components, enlarges macromolecules and generates carbonyl/sulfoxide groups. The number-average molecular weight, Mn, dominates low-temperature rheology. Higher rubber dosage (20%) and finer 80-mesh rubber slow component transformation and molecular aggregation, preserving relaxation capacity. Grey correlation and ridge regression prove S depends on heavy fractions while m responds more to light fractions, with optimal m prediction at −24 °C. Crumb rubber alleviates UV-cold coupled hardening by buffering light fractions and inhibiting molecular aggregation, offering micro-macro guidance for cold high-radiation asphalt design.