Simulation and Analysis of Influencing Factors of Pavement Thermal Environments in Guangzhou

Abstract

Pavements are closely related to the livelihoods of urban residents as an important part of the urban road system. Based on the early field measurements of our team, we found that plant spacing, pavement orientation, and pavement material influence the pavement thermal environment. Our objective was to quantitatively evaluate the influence of various factors on pavements in Guangzhou along West Zhonghuan Road, Guangzhou University. Based on our team’s previous research, environment-met (ENVI-MET) numerical simulation software was used to simulate pavements under different road orientations, underlying surface materials, and plant distances. Quantitative analysis of the effects of different factor combinations on the temperature, humidity, wind speed, physiological equivalent temperature (PET), and radiant temperature (Tmrt) was performed. The results show that among the various factors affecting the thermal environment of pavement, street tree spacing was found to have the greatest effect on the thermal environment of pavement. The effect of direction is negligible; however, it has a significant effect on the wind speed. There was no significant difference in the air temperature and relative humidity between concrete and asphalt. The average air temperature of red floor tile was slightly lower than that of asphalt and concrete. Reducing the spacing of street trees can effectively reduce the penetration of direct solar radiation, physiological equivalent temperature (PET), and temperature (Tmrt) and improve pedestrian walking comfort. The results can serve as a reference for pavement design in Guangzhou and improve the wellbeing of citizens and promote environmental sustainability.

Evaluation of Microclimate Benefits Due to Cool Pavements and Green Infrastructures on Urban Heat Islands

“…The thermal conductivity speeds up the top-down heat transfer [49], while the thermal capacity affects both the maximum and the minimum temperatures because it affects the thermal inertia [50]. According to the UHI mitigation strategies in the literature [51,52], this study takes into account the physical characteristics of the existing and the proposed road materials in Table 1 [53][54][55]. Light concrete pavers substitute the existing asphalt pavement, while green furniture and trees are added to the area.…”

Study on the Spatial and Temporal Distribution of Thermal Comfort and Its Influencing Factors in Urban Parks

“…On the whole, the distribution of temperature, heat index and wet-bulb globe temperature is generally the same, but the spatial distribution of humidity is opposite, showing high humidity inside the park, low perceived temperature and relatively cool, and low humidity near the park, high perceived temperature and relatively hot. The main reasons may be (1) high vegetation coverage and high humidity in the park [31] and (2) there are mostly cement roads outside the park, and the spacing between street trees is large [32]. Specifically, the areas with high thermal comfort are concentrated in the areas with dense vegetation inside the park or shaded by trees and high humidity near the artificial lake.…”

Evolution characteristics of precipitation phase in winter and its application in expressway weather forecast

“…Therefore, this study attempts to determine the slippery degree of road surface by combining the variation of pavement condition with the skid resistance performance of pavement, such as surface temperature, surface state and pavement pollutants. Based on the experimental and research results of Xie [16], Li [17], and Li [18], the surface slippery degree of expressway can be divided into the following situations according to the friction coefficient: (1) the friction coefficient of dry asphalt pavement maintains 0.50 above for a long time after a period of application;…”