MPC
Research Projects (2006-07)

Identifying Number

MPC-272

Project Title

Use of Wind Power Maps to Establish Fatigue Design Criteria for Traffic Signal and Variable Message Structures

University

University of Wyoming

Project Investigator

Dr. Jay Puckett, UWY
puckett@uwyo.edu

External Project Contact

Gregg Fredrick, WYDOT
gregg.fredrick@dot.state.wy.us

Project Objective

Validate the use of wind power maps to predict fatigue damage in traffic signal poles using DOT fatigue inspection data as the basis. Suggest specification modifications based upon the findings.

Project Abstract

Design criteria for traffic signal and other sign structures relies upon fatigue load criteria that are producing significant increases in joint size and cost. The cognizant design specification is the Fourth Edition of the AASHTO Luminaire and Traffic Signal Specification (2002 with interims). Without the fatigue requirements, these connections would be significantly different. Connection designs, specifically in the windy plain and mountain states, are significantly affected because of higher than average wind speeds. A new approach (or significant refinements in the present) is required to better define where fatigue design is truly required. The proposed research suggests using wind power maps to predict fatigue damage due to wind and guide designers in the quantification of the associated fatigue loads.

Task Descriptions

1. Collect more inspection data from state and local DOTs in windy/mountainous areas to expand the database.
2. Correlate the inspection data with the wind power in each area.
3. Draw conclusions regarding the application of wind power maps for the fatigue design of signal and sign structures.
4. Write draft specifications.
5. Submit final report.
6. Submit a technical paper to the Transportation Research Board.

Milestones, Dates

Starting Date: July 1, 2006
Ending Date: June 30, 2007

Yearly and Total Budget

$100,330

Student Involvement

One graduate student

Relationship to Other Research Projects

This research is not related to any other project known to the authors.

Technology Transfer Activities

Research product can be applied to the development of better design specifications for traffic signal supports and luminaires. The research results will be disseminated through a final report, technical paper, and conference presentations. If the research results are promising, draft specifications will be developed.

Potential Benefits of the Project

Modification of the AASHTO Luminaire and Traffic Signal Specifications will better quantify fatigue loads. Improved procedures could lead to decreased connection sizes over large areas and thousands of connections located in low wind power areas. It could also lead to rational design of large connections in high wind power areas where they are required. Significant savings in the connection cost and aesthetic qualities associated with smaller connections are likely.

TRB Keywords

Wind Load, Wind Power, Traffic Signal Pole, Luminaire, Fatigue, Fatigue Load