Title

MECHANISTIC ROUGHNESS MODEL BASED ON VEHICLE-PAVEMENT INTERACTION

Document Type

Journal Article

Publication Date

2000

Subject Area

operations - performance, infrastructure - vehicle, organisation - performance, mode - rail

Keywords

Wheel rail interaction, Vehicle dynamics, Unevenness, Tire pavement interface, Thickness, Surface roughness, Structural analysis, Stress analysis, Strain analysis, Roughness, Rolling contact, Repeated loads, Performance based specifications, Pavement performance, Pavement layers, Pavement design, Mechanistic design, Mathematical models, Flexible pavements, Finite element method, Finite element analysis, Equivalent single axle loads, Determination of stress, Cyclic loads, Axle loads

Abstract

A mechanistic roughness performance model that takes into account vehicle dynamics was developed in the form of a relation between roughness and number of load repetitions, axle load, and asphalt layer thickness. The model is completely mechanistic and uses vehicle dynamics analysis to estimate the dynamic force profile and finite element structural analysis to estimate the change of pavement surface roughness for each load repetition. The model makes use of the fact that pavement roughness changes the magnitude of the vehicle dynamic forces applied on the pavement and that the dynamic forces change the road roughness. The developed mechanistic roughness performance model can be used to estimate the 80-kN (18-kip) equivalent single-axle load for mixed traffic. The model can also be used to design pavement so that it will last for a certain number of load repetitions before reaching a predetermined roughness level. Performance-based specifications can be developed using the methodology presented in this study. The model has been calibrated and verified with field data elsewhere.