Preliminary Evaluation and Analysis of LTPP Faulting Data, Final Report
Primary Topic: Rigid Pavement
Description: A major goal of the Long-Term Pavement Performance (LTPP) study is the development of recommendations for improving the design and construction of new and rehabilitated pavements to provide longer lasting pavements. As part of the condition monitoring of the LTPP test sections, joint and crack faulting data are being collected on a regular basis at each jointed concrete pavement test site.
The LTPP faulting data are collected using the Georgia Faultmeter. Data are collected at joints and cracks along the wheelpath and along the outside pavement edge. As part of the study reported here, the quality of the faulting data was evaluated, and missing and questionable data were identified. The data were then used to develop faulting data indices (average joint faulting for each visit) and related statistical parameters.
Also, data analysis was carried out to determine the usefulness of joint faulting and related data in identifying factors that affect joint faulting. The analysis indicated that doweled joints exhibit very little faulting even after many years of service and that the effect of design features such as drainage, tied-concrete shoulder use, and joint spacing is not as significant when doweled joints are used. For non-doweled jointed plain concrete (JPC) pavements, the following design features were found to significantly reduce faulting: use of widened lanes, effective drainage system, stabilized base/subbase, and shorter joint spacing. Effect of faulting on ride quality was also investigated using jointed plain concrete pavements (JPCP) sections with three or more faulting and International Roughness Index (IRI) surveys. A strong correlation was found between rate of change in faulting values versus rate of change in IRI values for JPCP sections. The results indicate that faulting is a major component of increased roughness of JPC pavements.
FHWA Publication Number: FHWA-RD-00-076
Publication Year: 2000