Criteria for controlling rutting of asphalt concrete materials in sloped pavement

The development of rutting is one of the most common distresses in asphalt pavement. Especially at road sections with longitudinal slope, the problem is more serious than sections with no slope. This is because the slope decreases the average speed of vehicles running upward, so the total loading time increases dramatically. In China, dynamic stability (DS) in rutting test is used as the main experimental criteria to control the asphalt concrete (AC) materials before construction. It is supposed that the larger the DS index is means the material has better capability of retarding the ruts' development after constructed. Fixed DS criteria are set for diverse road situations. These differences in situations exhibit in structure and materials, traffic volume, climate condition and the gradient of sloped pavement. This paper aims at establishing a new control approach of AC material for dealing with rutting problem. Finite element method (FEM) is used to simulate two objects: specimen in rutting test and typical actual pavement with slope. In these simulations, the constitutive model of AC is the common basis. Through the model, specimen in rutting test and actual pavement are connected. It provides a possible way to control pavement rutting by computing and providing detailed criteria for specific project with special situations. These criteria change with actual, service circumstances of pavement. Compared with fixed criteria, they are more flexible, accurate and feasible for using in rutting control practice. (C) 2012 Elsevier Ltd. All rights reserved.