Introduction

About Pavement ME Design

Pavement ME Design (PMED) is a computerized release of the pavement design models presented in the AASHTO MEPDG Manual of Practice. In addition to providing an accurate and comprehensive means of performing pavement designs, PMED performs a wide range of analysis and calculations not available in other pavement design software. PMED is also fast, easy to use, and can streamline many repetitive tasks within your organization.

With its many customized features, PMED will help simplify the pavement design process and result in improved, cost-effective designs.

What’s New in PMED

PMED is the new generation of AASHTOWare® pavement design software which builds upon the research grade MEPDG software.

Features and Enhancements

Key features and enhancements found in PMED over the research grade MEPDG software include:

  • Increased computational speed
  • Tool to optimize for thickness design
  • Tool to import backcalculation results for rehabilitation designs
  • Ability to establish agency-specific libraries for materials, traffic and climate inputs Includes both SI Units and US Customary Units
  • Ability to import third party traffic data
  • Ability to enforce capacity limits on design traffic volume based on Transportation Research Board’s (TRB) Highway Capacity Manual (HCM) guidance
  • Ability to perform error checks on input data and report the outcome in a log file Ability to open, view and edit multiple projects at the same time
  • Ability to save and view structural responses (stress, strain and deflection) Tool to run sensitivity analysis of key inputs of a trial design
  • Ability to run multiple projects in batch mode and generate multiple project summary Tool to compare and view the differences in inputs between any two trial designs Includes an option for importing and exporting data directly from an agency’s
  • Enterprise-level relational database in both MS SQL and ORACLE environments

Project Design and Analysis using PMED

Each PMED pavement design project, whether new construction, an overlay, or restoration, uses an iterative process that follows three basic steps:

  1. Create a trial design for your project.
  2. Run PMED to predict the key distresses and smoothness for your trial design.
  3. Review the predicted performance of your trial design against the performance criteria and modify your trial design as needed until you produce a feasible design that satisfies the performance criteria. This step may require several runs of PMED.

Creating a Trial Project

Traffic, materials and climate inputs are combined with the pavement’s structural elements to develop a trial design. PMED uses a hierarchical approach for selecting some key inputs. In addition, the key design features and construction inputs are also used. For overlay and restoration design, additional rehabilitation-specific inputs are required. Design-specific performance criteria and their corresponding reliability levels are also defined.

Running PMED

Once all the inputs for the trial design are defined, run PMED to predict distress and smoothness over the pavement’s design life. PMED uses an incremental approach to calculate distress and smoothness. Increments can be as small as two weeks for new and rehabilitated flexible pavements and one month for new and rehabilitated JPCP and CRCP. In each increment, the daily and seasonal changes in material properties, traffic, and climate are considered. The cumulative distress and smoothness loss over the design life is the sum accrued in each time increment.

Review and Modify Trial Project Design

After PMED predicts distresses and smoothness for the trial design, it verifies the predictions against user-defined performance criteria at specified reliability. If the trial design meets the performance criteria, a feasible design has been reached. If not, the designer can modify the trial design as needed until all criteria are met.

NOTE: PMED has a feature that allows the automated determination of the design thickness of a selected layer within the pavement system to satisfy the user-defined performance criteria.