Analysis of Full Scale Test Data from National Airport Pavement Test Facility (NAPTF) to Determine Impact of Load Transfer Efficiency on Pavement Performance

摘要

Load transfer efficiency (LTE) is commonly considered as a measure of joint quality and it playsan important role in rigid pavement evaluation and design. Field evaluation of LTE includesmeasurement of loaded and unloaded deflections by means of falling weight deflectometer(FWD) testing and calculating deflection-based LTE. However, it is still important tounderstand whether deflection-based LTE provides sufficient information about joint andpavement life. The impact of joint LTE in addition to factors such as use of stabilized/ un-stabilized bases on early life of pavement has been studied in this research. The objective of thispaper is to determine whether deflection-based LTE measured in field correlates to jointdeterioration and pavement cracking. Additionally, the influence of base layers (stabilized/ un-stabilized) on joint quality and pavement early life (initiation of cracks) is also evaluated. Datagenerated from the full scale testing carried out by the Federal Aviation Administration (FAA) atNational Airport Pavement Test Facility (NAPTF) has been used in this study. A sharp increasein difference between recorded peak strains when the test vehicle approaches a joint at the samelocation but moving in opposite directions was identified as a parameter indicating crackinitiation. Based on the strain history recorded by the concrete strain gages, the trend of stress-based LTE as trafficking progresses was also studied. The need to consider traffic directionalsensitivity for joint modeling in finite element studies of jointed concrete pavement is alsohighlighted in this study.