Marquette University, Transportation Research Center, Department of Civil, Construction, and Environmental Engineering
Wisconsin Department of Transportation
Contract or Grant Number
This report presents the findings of a research study conducted to investigate the structural performance of a 275 mm hot mix asphalt perpetual pavement constructed as part of the WIM bypass lane at the Kenosha Safety & Weigh Station Facility. Two separate test sections were constructed using variable binder types and in-place air voids. Asphalt strain sensors were fabricated at Marquette University and installed during the construction of the HMA pavement. Sensors were positioned within the outer wheel path and located at the bottom of the 275 mm HMA pavement and at the interface between the lower layers at a depth of approximately 175mm from the surface. Strain sensors were oriented in both the transverse and longitudinal directions. A total of 16 strain sensors were installed during construction. Of these, only three survived to provide strain data under traffic loadings.
Deflection data obtained from FWD testing was used as comparative measures to strain measurements obtained during testing and to estimate the combined dynamic HMA layer moduli at the time of testing and to develop monthly trends of dynamic HMA layer moduli as a function of the expected mean monthly mid-depth pavement temperature. A comparative analysis of measured strains to those predicted from FWD measurements provided generally good agreement. A mechanistic appraisal of the constructed test sections was completed using the outputs of the EVERSTRESS pavement analysis program. This analysis computed the expected monthly damage induced by the application of 521,000 monthly ESAL loadings. The results of the mechanistic appraisal indicate the expected service life to 50% bottom-up fatigue cracking is in excess of 90 years for sections with air voids of 4% within the lower layers. If the air void content increases to 5% - 6% in the lower layers, the expected fatigue life may be significantly reduced to between 13 – 32 years.