Articles

Main Speaker - October 2016

“IH 345 – Overview of Feasibility Study, Finite Element Modeling and Plans for Retrofitting”

 Presented by: 
 Robert M. (Bob) Brown, PE, DBIA
Vice President and Area Manager
 WSP-Parsons Brinckerhoff  

and

 Samir Bougacha, PhD, PE
Senior Supervisiong Engineer
 WSP-Parsons Brinckerhoff 

The IH-345 Bridge is an elevated expressway linking I-30, I-45 and US 75 in Dallas, Texas. Completed in 1971, the twin northbound and southbound two-girder structures each approaching 1.7 miles in length contain both mainline and collector ramps. Since the 1990s, the bridge has exhibited distortion-induced fatigue cracking at the floor beam-to-girder connections. The structure is designated fracture critical and, because of its cracking history, is inspected annually by the Texas Department of Transportation (TxDOT). As part of a comprehensive study commissioned by TxDOT, a Parsons Brinkerhoff (PB)-led team was tasked with completing a full condition assessment and a finite element method (FEM) analysis of 63 of the units for the purpose of developing long-term fatigue retrofits for the bridge. Wiss, Janney, Elstner Associates, Inc. (WJE) led the condition assessment and field instrumentation portions of the work. This talk will discuss the methods used and challenges encountered in collecting large amounts of inspection and instrumentation data used to support the FEM modeling and retrofit decisions. 

Robert M. (“Bob”) Brown has 34 Years of Experience and received his B.S. in Civil Engineering from Texas Tech University in 1982.  Robert Brown serves as the area manager for Parsons Brinckerhoff’s Dallas office, having served in that role since 2011. He manages business development activities and project operations and serves as Project Manager on numerous projects.

Beginning his engineering career with TxDOT, Mr. Brown advanced from assistant engineer to area engineer in north Dallas supervising reconstruction of North Central Expressway N1, N2, and M projects. Later, as a consultant, Mr. Brown served as a project manager responsible for preparation of demolition contracts, as well as design of parking, streets and utilities for the American Airlines Center and Victory development.

He returned to TxDOT as deputy district engineer, and successfully led Comprehensive Development Agreement Procurement and Program Management for the following projects: I-635 Managed Lanes, North Tarrant Express Concession Agreement (I-820/SH 183), and the DFW Connector.

Samir Bougacha is a senior supervising engineer with WSP-Parsons Brinckerhoff, with over 2 decades of diverse experience in designing structural systems for bridge and facility structures.  Samir has a PhD in Structures from UT Austin (1990).  Since 2010 he has served as Adjunct Professor in Structures at Southern Methodist University.

Prior 2009, he worked with engineering consultant companies on building design that included residential, retail, commercial, hospitality, educational, healthcare, and industrial facilities.

Samir joined Parsons Brinkerhoff in 2009. His bridge experience includes new bridge design, widening of existing bridges, and rehabilitation of steel bridges. Samir serves as the Project Manager of the IH 345 Bridge Rehabilitation project. His responsibilities include supervising and working with engineers, design, quality control, project scheduling and preparation of final contract documents and construction cost estimate.