The analysis of variability of pavement indicators : MPD, SMTD and IRI. A case study of Portugal roads

Abstract

Macrotexture is one of the main pavement quality parameters considered in Portuguese Quality Control Plans which is not specifically addressed in data variability analysis studies. In this paper the ANOVA – Full Factorial method was used to analyse the variability of the Mean Profile Depth, the Sensor Measured Texture Depth and also the International Roughness Index. The ANOVA is appropriated to assess some sources of variation like repeatability and reproducibility and allow for the investigation of the contribution of several factors and interaction between them on the variability of a performance parameter. In this study data from five profilometers running on six long road sections was used. The investigated parameters were type of surface, operator and system and run repetition. Repeatability results were different for each parameter and factors analysis points to the necessity to further investigate the effect of the type of surface on data variability. The development of an operational plan to assure reproducibility is required.