Event Title

Using Helical Strakes on Pole Structures to Reduce Vibration from High-speed Winds

Location

CSU Ballroom

Start Date

20-4-2015 10:00 AM

End Date

20-4-2015 11:30 AM

Student's Major

Mechanical and Civil Engineering

Student's College

Science, Engineering and Technology

Mentor's Name

Fahrad Reza

Mentor's Email Address

farhad.reza@mnsu.edu

Mentor's Department

Mechanical and Civil Engineering

Mentor's College

Science, Engineering and Technology

Description

Metal pole structures are often used to support street lights and traffic lights and the primary force that they are subjected to is wind. The poles are susceptible to failure due to high-speed winds, but perhaps more seriously due to fatigue as a result of repetitive bending and torsion due to buffeting and vortex shedding. There have been accidents, some fatal, due to failing poles. Helical strakes have been used to support vertical structures (e.g. chimneys or outdoor piping) in the wind. In this project, the use of helical strakes on traffic light poles was investigated. First of all a detailed literature review of the topic was conducted. Next, a database of cases of failures as reported in the media was built. The relevant codes and design guidelines, particularly for Minnesota, were reviewed. Lab experiments were conducted using actual traffic light poles. Accelerations, wind speed, and pressure were measured both with and without helical strakes. The results indicate that helical strakes may be effective at reducing the vibrations of the traffic light poles. Because of the vulnerability of traffic lights to wind, implementing this technology on modern traffic lights might be an excellent solution to help them resist the effects of high-speed winds and become less expensive to maintain over time.

This document is currently not available here.

Share

COinS
 
Apr 20th, 10:00 AM Apr 20th, 11:30 AM

Using Helical Strakes on Pole Structures to Reduce Vibration from High-speed Winds

CSU Ballroom

Metal pole structures are often used to support street lights and traffic lights and the primary force that they are subjected to is wind. The poles are susceptible to failure due to high-speed winds, but perhaps more seriously due to fatigue as a result of repetitive bending and torsion due to buffeting and vortex shedding. There have been accidents, some fatal, due to failing poles. Helical strakes have been used to support vertical structures (e.g. chimneys or outdoor piping) in the wind. In this project, the use of helical strakes on traffic light poles was investigated. First of all a detailed literature review of the topic was conducted. Next, a database of cases of failures as reported in the media was built. The relevant codes and design guidelines, particularly for Minnesota, were reviewed. Lab experiments were conducted using actual traffic light poles. Accelerations, wind speed, and pressure were measured both with and without helical strakes. The results indicate that helical strakes may be effective at reducing the vibrations of the traffic light poles. Because of the vulnerability of traffic lights to wind, implementing this technology on modern traffic lights might be an excellent solution to help them resist the effects of high-speed winds and become less expensive to maintain over time.

Recommended Citation

Aldalbahy, Khalid and Moath Aldalbahy. "Using Helical Strakes on Pole Structures to Reduce Vibration from High-speed Winds." Undergraduate Research Symposium, Mankato, MN, April 20, 2015.
http://cornerstone.lib.mnsu.edu/urs/2015/poster_session_A/58