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Settlement and non-uniform deformation of frozen soil subgrade introduce fatal cracks on semi-rigid base asphalt pavements. This research aims to use reinforced wire mesh to reduce serious cracks on semi-rigid asphalt pavements in frozen regions. Three impact factors, diameter and interval as well as two types of wire mesh have been analysed by loading tests. Results have shown that after setting the reinforced wire mesh: (a) failure load and displacement of the cement-stabilised crushed gravel samples have been improved; (b) diameter and interval of the wire mesh have interactive impacts on reinforced sample load capacity; (c) the reinforced wire mesh can limit cracks by redistributing stress in the specimen; and (d) the multiple linear regression model well reflects the variation of loading properties; the results make sense from the statistics view as well. Results also represent that the strengthened wire mesh can help spread out the applied load, and increase the overall loading capacity of cement-st...

In this study, an idealised asphalt mixture was modelled with the discrete element method for both two-dimensional (2D) and three-dimensional (3D) cases. The air voids were randomly generated and counted within the models to reach a specific air void level (e.g. 6%). The 2D models were used to compute the strain and stress responses when the specimens were subjected to a compressive load. Then, the moduli of the specimens were computed from the stress–strain curves. The 3D idealised model was generated using a number of layered 2D models. The air void distribution patterns were also studied with 2D and 3D randomly generated models at specific air void levels. The results showed that the modulus deviation increases when the air void level increases. In addition, the modulus deviations of the 3D models were found to be much lower than those of the 2D models. When comparing the modulus predictions from the 2D models with those from the 3D models, the research proved that the 3D models yielded higher moduli t...

The objective of this paper is to use the discrete element model (DEM) to predict the asphalt mixture dynamic modulus in the hollow cylindrical specimen across a range of test temperatures and load frequencies. The microstructure of the asphalt concrete specimen was captured by X-ray tomography techniques. The hollow circular images were produced from the layer of cylindrical X-ray computed tomography (X-ray CT) images. The asphalt concrete images were divided into three phases according to a density index: aggregate, sand mastic and air void phases. The sand mastic phase was composed of fine aggregates (smaller than 2.36 mm) and asphalt binder. The distribution of air void, sand mastic and aggregate were also investigated along with the depth of the hollow cylindrical specimen. In the DEM simulation, the sand mastic's dynamic modulus using different loading frequencies and test temperatures was used to predict the asphalt mixture's dynamic modulus. The predicted dynamic modulus was at that same loading f...