A Study to Determine the Impact of Cracking on Load Transfer Efficiency of Rigid Airfield Pavements

摘要

The mechanistic evaluation of pavement utilizing full-scale test data is an important component to the study of pavement behavior. This study focuses on the use of concrete strain gages (CSG) and crack location data to evaluate the effect of localized cracking on the stress-based load transfer efficiency (LTE (S)) of transverse doweled pavement joints. Concrete strain gage data generated from the full-scale testing carried out by the Federal Aviation Administration (FAA) at the National Airport Pavement Test Facility (NAPTF) has been analyzed in this study. Load transfer efficiency was determined from paired concrete strain gages for the test vehicle moving in opposite directions at two specific locations, resulting in four distinct cases of LTE (S). It was found that LTE (S) varies as loading progresses on the test sections, especially after cracking near the joint has occurred on the slabs. The design constant of 25 % LTE (S) appears to be reasonably conservative before cracking occurs at the joint but overestimates joint LTE (S) thereafter. Additionally, peak strains from gages located at the joint can be used to evaluate the behavior of LTE (S) during the formation of cracks on the slab, in particular the case where the cracks have formed close to the doweled joint but are not yet visible on the surface.