Development of a Strategic Plan for the Implementation of the AASHTO 2002 Design Guide for TxDOT Operations

Project Description

The Mechanistic-Empirical (M-E) Design Guide software represents a major change in the way pavement design is performed. The program requires over 100 separate inputs, many of which had never been collected by the Texas Department of Transportation (TxDOT). This project evaluated beta versions of this software and was initiated to answer the following questions:

• Are the new input data significant under the climatic conditions and for the types of pavements typically built by TxDOT?
• What is the best path to pursue if TxDOT decides to adopt the new program?

To find out which of the variables in the program were sensitive, a set of inputs based on typical pavements built by TxDOT were developed for the northwest part of the state (dry-freeze climatic zone) and for the southeast area (wet-warm climatic zone). The program was calibrated for each case and then run for each case, changing a single variable each time, and the results were documented.

The M-E Design Guide will be an excellent resource for forensic evaluations to compare the as-built values to the proposed values and determine the impact of out-of-specification materials. It is perfectly suited to evaluate new materials and designs, including steel placement, modified asphalts, well-draining bases, etc. Although not recommended for routine design work in Texas, the M E Design Guide should certainly be considered for high-end pavement designs.

Project Publications

Sensitivity Analysis of and Strategic Plan Development for the Implementation of the M-E Design Guide in TxDOT Operations : Volumes 1&2 0-4714-1

Sensitivity Analysis and Strategic Plan for the Implementation of the M-E Design Guide in TxDOT Operations: Summary Report 0-4714-S

Texas Transportation Researcher Articles

Designing Pavements - Volume 41, Number 2

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