Effects of Various Design Features on Rigid Airfield Pavement Design

Regardless of a shorter or longer joint spacing, a better or worse load transfer mechanism, and environmental effects, the required minimum slab thickness will be the same using the current airfield pavement design procedure. Thus, the primary objective of this study is to investigate the effects of many design features including finite slab sizes, thermal curling, moisture warping, and the presence of a second subbase layer on rigid airfield pavements in attempts to expand the applicability of the proposed thickness design procedure by Lee and Yen. The Corps of Engineers full-scale test pavement data were reanalyzed. Several prediction models proposed by Lee, et al. were utilized to estimate the critical edge stress for design. Stress adjustment factors for finite slab width and length were determined and found to be negligible for the test data. Since the concept of transformed section was frequently utilized and sometimes misused in the literature to account for the stress reduction due to a bonded or unbonded second layer, a more complete treatment of this concept was presented. Subsequently, the stress adjustment factor was estimated assuming all subbase layers were unbonded. Climatic data close to the test track locations were obtained from the Long-Term Pavement Performance (LTPP) database and the stress adjustment factor due to effective temperature differentials was estimated. As a result, an alternative structural deterioration model was proposed for future trial analysis and design. The primary benefit of this study and recommendations for future implementation and investigations are discussed.