MODELLING OF FLEXIBLE PAVEMENT USING IITPAVE SOFTWARE AND ITS ECONOMIC ANALYSIS

This study focuses on the modelling and performance evaluation of flexible pavement using IITPAVE software, aligned with IRC: 37-2012 guidelines. Flexible pavements, widely used in India due to their cost-effectiveness and ease of construction, consist of layered structures designed to distribute vehicular loads efficiently. The research aims to assess how variations in thicknesses of the bituminous, base, and sub-base layers influence pavement life, particularly with respect to fatigue and rutting failures. A mechanistic-empirical approach was adopted, wherein resilient modulus values for each pavement layer were calculated based on material properties and environmental conditions. The IITPAVE software was used to simulate multilayered pavement systems and evaluate critical strain responses—horizontal tensile strain at the bottom of the bituminous layer and vertical compressive strain at the top of the subgrade. These strain values were then used to determine the pavement’s fatigue and rutting life using IRC equations. Various design alternatives were modelled by varying wheel loads and layer thicknesses. Design life charts were developed for each case, providing a visual reference for performance prediction. Furthermore, an economic analysis was conducted using SSR rates for Maharashtra (2024-25), estimating construction costs for 1 km of 7 m wide pavement. The analysis highlighted the cost-effectiveness of optimized designs while ensuring structural reliability. This research supports sustainable pavement design by promoting material efficiency, lifecycle cost reduction, and performance-based planning. It also aids in decision-making for engineers and policymakers by presenting economical and durable alternatives for road infrastructure development.