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In this study, 20-year and 40-year designs of common pavement types in USA at three traffic levels are examined for their environmental burdens, including hot mix asphalt pavement, jointed plain concrete pavement and continuously reinforced concrete pavement. The study first introduced a previously built life cycle assessment model in pavement engineering and then performed the detailed modelling for each pavement design, with special efforts devoting to the delay estimation of in the congestion module and the usage module (roughness effect on the fuel economy). In the context of this study, regarding the multiple environmental indicators, it is found that 40-year pavement designs do not necessarily carry environmental advantages over their 20-year counterparts, being only possible at ‘high’ traffic volumes. Sensitivity analysis indicates that the influences of stress developing rate, recycling, feedstock energy of asphalt binder and maintenance strategy are less significant compared to that of traffic volume. In the life cycle inventory, material module and usage module are two dominating contributors; share of congestion module due to construction and maintenance activities grows quickly with the increase of traffic volume. [ABSTRACT FROM AUTHOR]