Effect of environmental and geographical conditions on asphalt pavement performance: A case study on State Route in Tennessee, USA

Pronounced regional disparities in asphalt pavement performance across Tennessee, particularly in the western part of the state, prompt this study into the underlying environmental and geographical factors. This study analyzed Tennessee Department of Transportation (TDOT) pavement condition data alongside climatic, soil, and material information for selected State Routes. The analysis was supplemented by field Falling Weight Deflectometer (FWD) testing and laboratory evaluations of core samples using Indirect Tensile (IDT) resilient modulus tests, the IDEAL Cracking Test (IDEAL-CT), and Fourier Transform Infrared Spectroscopy (FTIR). Results revealed that pavements in West Tennessee exhibited significantly greater rutting, higher roughness, and lower condition indices than those in other regions. This underperformance is attributed to the combined influence of factors such as elevated temperatures that accelerate binder aging and rutting, severe moisture from high precipitation and shallow groundwater that exacerbate damage in poorly draining soils, and the prevalent use of moisture-susceptible aggregates. These findings demonstrate that uniform statewide design standards are insufficient for Tennessee's diverse geotechnical conditions. To improve pavement longevity, this study recommends adopting regionally calibrated specifications, including climate-adaptive binders, enhanced subsurface drainage, subgrade stabilization, and material requirements that mandate moisture-resistant aggregates or anti-stripping additives. The insights are broadly applicable, highlighting the critical need for transportation agencies to integrate local environmental and geotechnical data into pavement design and asset management.