Current AASHTOWare Pavement ME Design (PMED) predictions for slab warping in jointed plain concrete pavements (JPCPs) are based on empirical models that do not adequately reflect environmental influences, such as drying shrinkage, internal relative humidity, and construction conditions. These limitations can result in underestimating warping-related cracking and pavement roughness, which reduces performance and increases maintenance needs.

Warping develops early in the slab’s life due to differential drying shrinkage, particularly in regions with drought, wind, and arid conditions. The Enhanced Integrated Climatic Model (EICM) in PMED is capable of modeling internal slab humidity using diffusion theory but is currently inactive and uncalibrated. Furthermore, current cracking transfer functions in PMED incorporate warping effects indirectly without accounting for individual contributing factors, such as creep, support conditions, slab restraints, and curing practices.

Improving warping predictions in PMED will allow designers to more accurately assess slab performance under environmental loads, optimize pavement designs, and reduce life-cycle costs, all of which are critical to building sustainable and resilient infrastructure.

The objectives of this research are to (1) develop and calibrate new slab warping models for integration into AASHTOWare PMED using internal humidity and shrinkage behavior as key inputs and (2) recommend revisions to PMED and AASHTO design procedures.

Potential research tasks include:

·        Conduct a literature review of warping and drying shrinkage models, including creep and subbase effects.

·        Review and select appropriate data from the Long-Term Pavement Performance Program and other sources for model development and calibration.

·        Survey state DOTs to collect relevant field and mixture data related to shrinkage and cracking.

·        Develop new AASHTO slab-warping prediction procedures based on internal relative humidity.

·        Identify or develop individual component models (e.g., shrinkage, humidity, restraints).

·        Calibrate and validate the model using field data across climates and pavement types.

·        Recalibrate PMED cracking transfer functions as necessary.

·        Recommend updates to PMED and AASHTO guidance documents.