ASSESSING PERFORMANCE THROUGH THE UTILIZATION OF LIGHT WEIGHT DEFLECTOMETER

Abstract

Rapid infrastructure development, particularly in India, has emerged as a prominent global trend. Over the past few decades, it has become apparent that many road projects necessitate early-stage maintenance. To identify the underlying causes, a comprehensive structural evaluation study is imperative to assess the existing material properties of pavements. While Light Weight Deflectometer (LWD) is gaining widespread acceptance and popularity as an in-situ spot-testing device worldwide, in India, only a few researchers have delved into its applications. This study aims to estimate the in-situ layer moduli of flexible pavements using LWD and further utilize these layer moduli for performance analysis. A series of tests were conducted at NH-15 on 52 distressed locations, and samples were systematically collected for subsequent laboratory testing. LWDmod software was employed to calculate the back-calculated modulus for each layer. The results revealed that the Coefficient of Variation (CV) of the back-calculated average modulus on both the Left-Hand Side (LHS) and Right-Hand Side (RHS) ranged from 24% to 30% for the bituminous surface, 33% to 45% for the WMM, 35% to 45% for the GSB, and 40% to 52% for the Sub-grade. It was observed that the CV value was higher for softer materials and subsequently decreased for granular layers. The performance analysis indicated that the existing pavement is structurally distressed.