Sensitivity analysis of plastic deformation on flexible pavement structures Análisis de sensibilidad de la deformación plástica en las estructuras de pavimento flexible

Abstract

In Colombia, one of the most frequent damages of flexible pavement structures is the plastic deformation commonly known as rutting, which consists of a channelized depression in the circulation footprint of vehicles produced by the effect of traffic loads, variations in the service temperature of the pavement, deficiencies in the design and construction of asphalt mixtures or due to the presence of weak subgrade. The rutting hinders the maneuverability of vehicles, reduces road safety and affects the comfort level for the user. The objective of this research is to perform the sensitivity analysis of the variables that influence accumulated plastic deformation or rutting in flexible pavement structures using the mechanistic model. The study of the plastic deformation or rutting was carried out by applying the methodology presented in the guide for the mechanical - empirical design of flexible pavements "Mechanistic-Empirical Pavement Design Guide - MEPDG" developed by the AASHTO (American Association of State Highway and Transportation Officials) versions 2008 and 2015, which is one of the most widely implemented methodologies for the design of new pavement structures, as well as for their maintenance and rehabilitation. The scope of the study is at the theoretical modeling level in order to understand the phenomenon of permanent plastic deformation of flexible pavement structures. The study shows that the variables most sensitive to rutting of flexible pavement structures are: the weighted annual average temperature - TMAP, followed by the design traffic, the dynamic modulus of the asphalt mixture, the load per tire, the thickness of the asphalt layer, the contact pressure and depth of the bearing layer; This information is very useful for pavement structure design engineers.