Structural Behavior of Long Span Overhead Sign Support Bridges

Ishtiaque Ahmed Tuhin

doi:10.4236/ojce.2020.101001

Abstract

Overhead sign-support bridges that allow displaying necessary information for travelers across the multiple lanes in highways often use large message sign panels: static message sign (SMS) panels or dynamic message sign (DMS) panels. Along with conventional SMS panel, the use of DMS panel is increasing in highways over time owing to their effective capability to guide the travelers in real-time. A 230-ft long span 4-chord overhead steel truss bridge attached with SMS and DMS panel has been studied through extensive finite element analysis to observe the structural integrity. The static wind load was applied in model truss for four different configurations as per 2016 AASHTO LRFD design specification. The innovative structural detailing approach for truss end support and connection detailing for toll-equipment supporting frame was proposed based on static analysis. The present study will help engineers to design overhead sign support bridges by ensuring both public safety and structural integrity.

Highlights

A 230-ft long span 4-chord overhead steel truss bridge attached with static message sign (SMS) and dynamic message sign (DMS) panel has been studied through extensive finite element analysis to observe the structural integrity
The large highway support signs are used on freeways, expressways, and major arterials for better management of traffic flow by providing accurate and timely information to travelers that can be classified as static message sign (SMS) and dynamic message sign (DMS)
The goal of this study is to provide design guideline for long-span overhead sign bridges, where designers will have the flexibility for using of SMS or DMS panel or both

Summary

Introduction

The large highway support signs are used on freeways, expressways, and major arterials for better management of traffic flow by providing accurate and timely information to travelers that can be classified as static message sign (SMS) and dynamic message sign (DMS). New innovative approach “impact of road profile” will be applied in this model truss This extensive research works can be categorized as: Task 1-Structural integrity of long span overhead sign support structures following current code specifications; Task 2-Artificial wind gust under extreme weather condition through CFD analysis; Task 3-Fatigue behavior because of natural wind gust pressure along with truck induced pressure, galloping, and vortex shedding; Task 4-Thermal expansion, diurnal temperature change, and damage during transportation; Task 5-Heavy truck induced load and impact of road profile. This innovative research work will contribute as a great aid along with the DOTs existing design guideline for overhead sign support bridges

Finite Element Modeling

Preliminary Static Analysis Result and Discussion

Findings

Conclusion