Influence of Trajectory Deviation on the Calculation Accuracy of International Roughness Index

This study investigates the application of vehicle-mounted road laser profilometers in road roughness detection and the challenges they encounter, with a focus on analyzing the impact of trajectory deviation on the International Roughness Index (IRI). IRI, a recognized evaluation metric for road surface roughness, quantifies pavement wear and durability. However, longitudinal elevation measurements in wheel-track areas are susceptible to interference from factors such as operators and detection equipment, leading to deviations of the measurement trajectory from expectations and subsequently affecting the accuracy of IRI calculations. To address this, the study employs a combined theoretical and experimental approach to thoroughly analyze the influence of trajectory deviation on IRI measurements and proposes an optimization strategy: after eliminating the IRI data with the largest deviations, the coefficient of variation for the remaining data is recalculated to enhance the accuracy of the measurement results. Experimental results demonstrate that this strategy can effectively identify and exclude anomalous data, significantly improving the reliability and stability of IRI measurements. This study provides valuable insights for road roughness detection and contributes to enhancing the precision and efficiency of pavement performance assessments.