An analytical procedure for strain response prediction of flexible pavement

Abstract

The bottom-up fatigue damage in flexible pavements is typically assessed through the tensile strains at the bottom of the asphalt layer. The fatigue damage is then correlated using a calibration factor to the fatigue cracking. Therefore, the success of any pavement design depends on the accuracy and efficiency of employed mechanistic parameters, such as stress and strain. A procedure that can accurately and rapidly predict pavement strain response when traffic and environmental data are provided is desirable. In this study, an analytical procedure was developed to predict pavement response using a mixed pool of tensile strains from instrumentation and 3D FE simulation. Statistical features make the developed procedure powerful and efficient such that the strain responses due to every individual axle pass can be predicted. A demonstration example of predicting tensile strains under multiple-axle loading conditions is provided to facilitate application of the procedure to other data-sets. The maximum difference of 9 microstrain in response implies a reasonable accuracy of the analytical procedure. As demonstrated by using a full-depth flexible pavement section, the analytical procedure is effective and of immediate assistance to experimentally compare design alternatives.

Keywords:

• strain response
• flexible pavement
• finite element
• fatigue damage
• analytical