Monthly Technical Presentation and Dinner Meeting
Thursday, November 21, 2013

Topic: Development of Fatigue Design Provisions for Highway Sign, Signal and High Level Luminaire Support Structures - 1.0 PDH

Location:   Radisson Valley Forge Hotel and Conference Center
1160 First Avenue, King of Prussia, PA 19406

Cost:  members $45; non-members $50; students $15

Wind induced fatigue cracking is one of the primary modes of failure of highway sign, signal and high level luminaire support structures. Although fatalities from failure of these structures have been rare, the potential risk of property damage and safety hazards remain high, and the economic impact of inspecting, maintaining and replacing the sheer volume of existing structures remain paramount. Traditionally, the subject structures were seldom designed against fatigue fracture. In absence of sufficient experimental database, fatigue resistance of the various connection details in these structures was never well established and the existing specifications remain deficient. Recently, a comprehensive research program was conducted at Lehigh University under the NCHRP Project 10-70, where fatigue performance of several critical welded connections in subject structures were evaluated by extensive analytical and experimental studies. As part of these studies, fatigue resistance of connection details in the existing inventory were defined and new cost-effective fatigue resistant alternatives were developed. About 80 full size galvanized specimens of sign, signal and high level luminaire support structures containing different welded connections were fatigue tested. Using parametric Finite Element Analyses (FEA) verified by test data, fatigue performance of the connections in both finite and infinite life regimes were evaluated and optimized over the range of applicable geometric dimensions. New specification recommendations were developed based on these research findings for cost-effective design of sign, signal and luminaire support structures in highway infrastructure. These significant revisions were incorporated into the latest AASHTO Standard Specifications for Support Structures for Highway Signs, Luminaires and Traffic Signals, 6th ed., 2013.

Dr. Sougata Roy is a Principal Research Scientist with the ATLSS Engineering Research Center, at Lehigh University. Sougata received a Baccalaureate degree in Civil Engineering from the University of Calcutta in India, and Masters and Doctoral degrees in Civil Engineering from Lehigh. Roy is an expert in Structural Engineering with specialization in Fatigue and Fracture of Steel Structures. He is leading funded research in System Performance Evaluation, Deterioration and Damage Assessment, Failure Analysis, Forensic Studies and Life Cycle Prediction of Bridge and Highway Infrastructure, including simulation of large systems by

advanced Finite Element Analysis, laboratory experiments and field measurements. Dr. Roy teaches undergraduate and graduate level courses on Bridge System Design, and Fatigue and Fracture of Steel Structures at Lehigh, and supervises doctoral, masters and undergraduate students with the Department of Civil and Environmental Engineering. He also offers courses for Pennsylvania Department of Transportation on Fatigue and Fracture Design of Steel Bridges.

Meeting schedule:
5:30-6:30 Social and Registration
6:30-7:15 Dinner (chicken/fish/vegetarian) - please note preference in response
7:15-8:30 Program

To register (REQUIRED):
Please email Khalid Shaikh at:
Tel: (215)896-6264 by 11/19/2013    
Mail check payable to SEI-Phila Chapter to SEI Treasurer Mr. John Millius, c/o AECOM
1700 Market Street, Suite 1600, Philadelphia, PA 19103
T 215.735.0832  F 215.735.0883 ,  or bring it to the meeting.

Note:Should you decide to cancel your registration, it must be done at least three days prior to the scheduled meeting date. Any cancellation made within three days is subject to pay the full meeting rate.