Determination of Equivalent Temperature for Asphalt Pavement Design in Vietnam

Temperature is a critical factor influencing asphalt pavement performance and its service life. Current pavement design practices in Vietnam, however, rely on fixed temperature values, disregarding regional climatic variations. To address this limitation, this study introduces a revised concept of "equivalent temperature", which is a representative temperature value that accounts for daily temperature fluctuations over a 20-year period. The objective is to enhance the accuracy and durability of pavement design by determining region-specific equivalent temperatures. Utilizing temperature data from 127 weather stations spanning 20 years, a gridded temperature map of Vietnam is constructed. The Shell method is employed to calculate Weighted Mean Annual Pavement Temperatures (WMAPTs) for each station. Results reveal significant spatial variability in WMAPTs across the country, ranging from 30°C to 41°C. These findings underscore the inadequacy of a singular design temperature for Vietnam's diverse climate. The calculated WMAPTs offer a valuable dataset for estimating asphalt moduli and informing future pavement design and research efforts, ultimately contributing to improved pavement performance and extended pavement service life in Vietnam.