Evaluación de metodología AASHTO y SHELL para el diseño de pavimento de la vía “Caracolí” que conecta a “la carretera del amor” en Villavicencio - Meta

Abstract

Nowadays, the world has different methods for the design of flexible pavements that differ from each other, due to the equations and level of information they require. Although it is true that the AASHTO 93 method is used in Colombia, it is valid to question the advisability of exploring and analyzing other methods that could be applicable in the country. Bearing in mind the above, in this project the semi-empirical (AASHTO 93) and mechanistic-rational (SHELL 78) design methods were studied and compared. Taking this in place, a theoretical comparison of the selected methods was carried out in the first instance in terms of the approach and the level of information required by each method. Subsequently, a comparison was made of the results obtained by the different methods, in a series of scenarios defined for the "Caracolí" road, in the small townof Villavicencio at Meta, according to variables of traffic, subgrade and weather as well as in terms of layer thicknesses and cost of materials. Furthermore, the results indicated that the most conservative method, considering the thickness of the layers of a flexible pavement structure and the costs that this implies, is the AASHTO 93 method. Nonetheless, the method that considers a greater amount of information is by SHELL 78 because it has managed to determine the combinations of thicknesses of the different layers of the pavement that tensile strain in the asphalt layers (εt) and vertical compression strain in the subgrade (εz) values during the design period, this method assumes the pavement structure as a linearly elastic multilayer system, under the management of the traffic loads, in which materials are found by their modulus of elasticity. The main recommendation is to complement the results obtained with more updated programs that incorporate a complete data analysis according to an empirical-mechanistic method.