A Comparative Analysis of Flexible Pavement Design using IRC 37-2012 and IITPAVE Software

Abstract

Objectives: To conduct a comparative analysis of pavement design methodologies adopted by the Indian Road Congress (IRC) 37-2012, based on the empirical method and mechanistic-empirical approach adopted by the IITPAVE software. Methods: The present research is carried out to design pavement crust thickness and calculate the strain values in pavement by adopting IRC 37-2012. Pavement crust thickness is designed based on real-time traffic and soil data collected for a stretch of road in Tamil Nadu, India. The allowable horizontal tensile strain and vertical compressive strains are estimated by the empirical equations proposed by IRC 37-2012 and the mechanistic-empirical method by IITPAVE software. A comparison of both design methodologies is made to check for their safety. Findings: Based on the soil data and traffic data from the stretch of road, the California Bearing Ratio (CBR) of the soil sample and design traffic in terms of million standard axles (msa) were computed to arrive at a total pavement crust thickness of 575 mm by adopting IRC 37-2012. The obtained values of allowable horizontal tensile strain at the bottom of the bituminous layer from IRC 37-2012 and the actual strain values from IITPAVE software are 301.73x10 -6 and 270.4x10 -6 respectively. Similarly, the allowable vertical compressive strain on the top of the subgrade soil surface and the actual strain values from IRC 37-2012 and IITPAVE software are 583.98x10 -6 and 381.6x10 -6 respectively. The analysis of the research shows that the actual compressive and vertical strain values obtained from IITPAVE are within the allowable strain values as per the code provisions of IRC 37-2012, making the design safe. Novelty: The novelty of the study lies in its approach to distinguishing itself by focusing on real-time data collection, analysis, and design of pavement. Furthermore, the design is checked for safety by using the latest available software.