DEVELOPMENT OF TEMPERATURE PREDICTION MODEL FOR FLEXIBLE PAVEMENTS

Abstract

A flexible pavement structure is a layered system consisting of different types of materials in different layers. Among the different layers, the bituminous layers play a significant role in its performance and longevity. However, being a viscoelastic material in nature, it shows temperature-dependent behavior. The prediction of the pavement temperature is quintessential for various applications, including pavement design, maintenance, and safety. This necessitates determining or predicting the temperature state of the bituminous layers as accurately as possible for ascertaining their strength characteristics. Most of the prevalent guidelines of different countries suggested the determination of pavement temperature either through a destructive approach or adopting the deterministic models developed in entirely different climatic regions. Although many studies were conducted across the globe to develop temperature prediction models, but their application for Indian conditions is not satisfactory due to their inherent limitations. Therefore, the present study envisaged developing a prediction model for determining the pavement temperature in hot climatic conditions like India. An instrumented test track was constructed to monitor the temporal variations of pavement temperatures across different seasons of the year. The temperature sensors were embedded at different depths from the pavement surface to record the spatial variations of pavement temperature. The collected dataset of pavement temperatures was further analyzed to develop the prediction model. Likewise pointed out in earlier studies, the influence of air temperature was observed to be quite dominant on the pavement temperature. The diurnal and seasonal changes of air temperature compel the pavement temperature to follow almost a similar pattern. Although the coherent relationship between the two temperatures was quite established, the present study emphasized on benefit of incorporating the influence of historical air temperature. A correlation study between the pavement temperature and average air temperature computed for different preceding periods of up to 72 hours was conducted. The number of preceding hours was found to be dependent on the required depth from the pavement surface under consideration and varied in a range of 3 to 11 hours.