关键词: |
Pavement design, MEPDG(Mechanistic-Empirical Pavement Design Guide), Design reliability, Calibration coefficients, Pavement Management System, Development, Pavement structures, Implementation guidelines, Louisiana, Flexible pavements, Rigid pavements |
摘要: |
The AASHTOWare Pavement ME(Trade Name) Design is the next generation of AASHTO pavement design software, which builds upon the newly developed NCHRP Mechanistic-Empirical Pavement Design Guide (MEPDG). Pavement ME(Trade Name) reflects a major change in the methods and procedures engineers use to design pavement structure and represents the most current advancements in pavement design. In preparation for DOTD to adopt the new design guide, there is an urgent need to evaluate the MEPDG pavement design software based on typical Louisiana pavement structures and local conditions. This study selected a total of 162 projects (pavement sections) from the existing DOTD highway network for the evaluation of MEPDG pavement design, local calibration, and validation of Pavement ME in Louisiana. The selected projects consisted of flexible pavements with five types of base (asphalt concrete base, rubblized PCC base, crushed stone or recycled PCC base, soil cement base, and stabilized base with a stone interlayer), rigid pavements with three types of base (unbound granular base, stabilized base, and asphalt mixture blanket), and HMA overlay on top of existing flexible pavements. Pavement design information including structure, materials, and traffic were retrieved from multiple network-level data sources at DOTD. A Louisiana default input strategy of Pavement ME that reflects Louisiana’s condition and practice was developed from results of sensitivity analysis. In addition, based on a consensus distress survey and pavement management system (PMS) distress triggers, the design reliability and performance criteria were established for different highway classes in Louisiana. The predicted performance from the Pavement ME was then compared with the corresponding measured performance retrieved from PMS. The analysis results indicate that the Pavement ME’s nationally-calibrated distress models generally under-predict alligator cracking, but over-predict rutting for DOTD’s flexible pavement types. For rigid pavements, Pavement ME over-predicts slab cracking but under-predicts joint faulting. For those nationally-calibrated distress models that showed constant bias and large variation, local calibration was carried out against the performance data retrieved from PMS. After the local calibration, the Pavement ME designs were verified by additional projects outside of the evaluation projects’ pool. Based on the results of this study, an implementation guideline document was prepared. The document contains all necessary design input information and calibration coefficients for DOTD to use the latest MEPDG software on a day-to-day basis for design and analysis of new and rehabilitated pavement structures in Louisiana. |