Performance Study on Flexible Pavements

The flexible pavement is composed of various materials and it experiences heterogeneous traffic and critical environmental conditions throughout its lifespan. The combined effect of traffic volume and environment conditions drives to the deterioration of flexible pavements with the passage of time. In fact, the pavement undergoes continuous deterioration under worst climatic conditions even in the absence of traffic. Long-term pavement performance study on flexible pavements is of greater importance to provide systematic maintenance and to prioritise the sequence of maintenance and rehabilitation of the road. It is economical and appropriate to provide regular maintenance/ rehabilitation rather constructing the new pavement after reaching worst conditions. In this research work, four road sections were selected to carry out the long-term pavement performance study. The performance study was carried out by assessing the functional and structural conditions of the selected pavements. The selected pavement sections were studied for traffic volume, the functional, and structural condition in terms of IRI by using MERLIN, pavement condition rating based on distress survey, rebound deflections from BBD technique, in-situ CBR value of subgrade calculated from DCP, and laboratory tests. Comparative study was made for selected road sections in terms of deterioration of pavement condition and growth of roughness and deflections with the time. An attempt has been made to develop the roughness and Pavement Condition Index prediction models using the MSN and CSAL as the explanatory variables. Prediction of future conditions is greatly helpful to optimise the scheduling of rehabilitation activities and to determine the funding level demanded to accomplish the predestined level of performance.