Developing a distress-based traffic equivalency to efficiently evaluate the effect of traffic loads on pavement performance

ABSTRACT

Traffic loading is considered one of the main factors contributing to pavement deterioration. Large illegal loads in the form of vehicles traveling with axle loads above the permissible legal limits and/or overall overweight magnify the traffic impact on the performance of pavements. These overloads contribute to the deterioration of pavement sections which leads to substantial maintenance and repair costs. This paper illustrates an example of an approach to determine the effect of both normal and overweight loads on the performance of rigid pavements using the Long-Term Pavement Performance (LTPP) traffic data. The traffic load was evaluated by estimating the legal and illegal ESALs related to both fatigue and erosion damage by visual observation and by field-assessment of the degree of bonding based using the Falling Weight Deflectometer (FWD). The illustrated example utilized LTPP data from nine Jointed Plain Concrete (JPC) pavement sites with different traffic mixes. This study reveals that the damage in JPC pavements could be either (i) visible by the formation of transverse cracking as would be related to fatigue related ESALs or/and (ii) invisible by the reduction of the effective thickness as would be related to erosion ESALs.

KEYWORDS:

• Fatigue ESALs
• erosion ESALs
• Falling Weight Deflectometer
• Jointed Plain Concrete Pavements
• neural network

Disclosure statement

No potential conflict of interest was reported by the author(s).