Road geometric information and a digital model based on light detection and ranging (LiDAR) can perform accurate geometric inventories and three-dimensional (3D) descriptions for as-built roads and infrastructures. However, unorganized point clouds and complex road scenarios would reduce the accuracy of geometric information extraction and digital modeling. There is a standardization need for information extraction and 3D model construction that integrates point cloud processing and digital modeling. This paper develops a framework from semantic segmentation to geometric information extraction and digital modeling based on LiDAR data. A semantic segmentation network is improved for the purpose of dividing the road surface and infrastructure. The road boundary and centerline are extracted by the alpha-shape and Voronoi diagram methods based on the semantic segmentation results. The road geometric information is obtained by a coordinate transformation matrix and the least square method. Subsequently, adaptive road components are constructed using Revit software. Thereafter, the road route, road entity model, and various infrastructure components are generated by the extracted geometric information through Dynamo and Revit software. Finally, a detailed digital model of the road scenario is developed. The Toronto-3D and Semantic3D datasets are utilized for analysis through training and testing. The overall accuracy (OA) of the proposed net for the two datasets is 95.3 and 95.0%, whereas the IoU of segmented road surfaces is 95.7 and 97.9%. This indicates that the proposed net could accomplish superior performance for semantic segmentation of point clouds. The mean absolute errors between the extracted and manually measured geometric information are marginal. This demonstrates the effectiveness and accuracy of the proposed extraction methods. Thus, the proposed framework could provide a reference for accurate extraction and modeling from LiDAR data.

Ecological restoration is difficult on the red clay highway slopes in the rainy areas in South China that experience severe soil erosion. By using the hydrophilic polyurethane material W-OH to solidify and protect red clay slopes, the erosion control will be substantially improved. We employed simulated rainfall erosion experiments and pot experiments to evaluate the anti-corrosion and growth promotion performances. We found that, (1) in the initial stage of protection, W-OH had the effect of accelerating slope drainage, solidifying the soil structure, and reducing soil loss, with the sediment reduction benefit reaching 37.4–65.3%. (2) The anti-erosion effect was mainly based on soil solidification. (3) The W-OH was affected by rainfall intensity and the W-OH concentration, and the soil erosion prediction equation was constructed according to the observation. (4) W-OH had a promising water retention performance and can promote the germination and late growth of slope plants to reduce the influence of eluviation. (5) The suitable W-OH solution concentration was 3–5% for slope protection herbs and shrubs, which were commonly used in South China. (6) The reduction in porosity was the fundamental cause of water retention improvement. The ecological restoration of slopes is a comprehensive process. Therefore, both anti-erosion performance and later plant growth are necessary. Our research provides a theoretical and experimental basis for applying the W-OH in the ecological restoration of the red clay slopes in subtropical areas and expanding the scope of the W-OH.

The dynamic modulus of asphalt mixture was one of the most essential parameters for predicting responses and performance of pavement structure in pavement design. The AASHTO 2002 Pavement Design Guide proposed a standard method to determine the dynamic modulus of the asphalt mixture under uniaxial compression test. However, many researchers in recent years have indicated that the dynamic modulus determined by uniaxial compression test could not be used for evaluation of existing pavement cores. Therefore, it is necessary to find an alternative method for dynamic modulus testing. The comparison study between two test methods of indirect tension and uniaxial compression was conducted in this paper. The measurement system of gage-point-mounted was adopted to determine the dynamic modulus of asphalt mixture under indirect tension using five types of asphalt mixtures with different binder types and nominal maximum aggregate size. The master curves of dynamic modulus and phase angle at a reference temperature of 20°C were obtained according to the superposition principle of time and temperature. The results showed that there were distinct differences in dynamic modulus, phase angle, and shift factor of asphalt mixture measured using two test modes. The correlation relationship of the fitted formulas demonstrated a significant correlation between dynamic modulus under uniaxial compression and indirect tension.

Icy pavement is one of the primary causes affecting driving safety in winter, and deicing asphalt mixture could effectively resist pavement icing. This study evaluated the effect of a slow-release deicing agent on pavement performance and ice-melting characteristics of the asphalt mixture. The asphalt mixture containing four different contents (0%, 30%, 50%, and 70% using the internal mixing method) by replacing mineral filler was designed. Pavement performance tests were used to investigate the effect of the deicing agent on the high-temperature stability, cracking resistance, and water stability of the asphalt mixture. Qualitative and quantitative tests were designed to compare the ice-melting characteristics and predict the ice-melting durability with different replacement amounts. The experimental results show that the high-temperature stability, low-temperature cracking resistance, and water stability of the asphalt mixture decrease with the increase inthe deicing agent. The mineral filler with a content of 50% deicing agent will enhance the stability of the mixture in the short term. Deicing asphalt mixture can significantly improve the ice and snow melting ability of the pavement, and the asphalt mixture with a content of 50% deicing agent will reduce the interface adhesion between mixture and ice by more than 55%. The slow-release deicing asphalt mixture can reach the maximum release concentration within two hours under rain and snow. The recommended replacement amount of slow-release deicing agent is 50%, and the predicted durability of deicing asphalt mixture is 5–8 years.