Potential Impacts of Longer and Heavier Vehicles on Texas Pavements

Abstract

This paper discusses the impacts of heavier and longer combination vehicles (LCVs) on the pavements of five major Texas corridors. These corridors were divided into 152 segments presenting uniform pavement properties and truck volumes. For each segment, axle load spectra were estimated for the baseline (existing) scenario and an LCV scenario was developed in concert with industry stakeholders and transportation officials. Axle weight data came from 10 weigh-in-motion stations. Pavement lives under both scenarios were estimated using elastic theory and classical fatigue equations. Non-significant impacts happened when both lives were 30 years or longer, or when the difference between lives was under one year. The LCV scenario had no impact on rigid pavements, decreased the life of some flexible pavements, and was less detrimental than the baseline in segments carrying overweight axles. Annualized overlay cost differences were calculated for all segments with significant LCV impacts. Total cost decreased. This paper’s primary contribution is a viable methodology to verify whether specific increases in vehicle axle or gross or weights have undue impacts on pavement costs.