Oklahoma Statewide Vessel Collision Risk Assessment
Overview

On May 26, 2002, the I-40 Webbers Falls Bridge over the Arkansas River was struck by a tugboat towing a series of barges. The impact rocked the bridge, sending a 580-ft section of the interstate, along with multiple cars and trucks, into the river below. Fourteen people perished in the tragic event. Both the Public and Oklahoma Department of Transportation (ODOT) officials demanded to know how this could happen. And could it happen again to other bridges in the area? To begin answering these tough questions, ODOT sought the input of an experienced bridge engineering firm. 

For the emergency collapse investigation, Modjeski and Masters (M&M) first determined barge collision loads, and created finite element models for in-depth analysis. In addition, our engineers evaluated materials samples and testing data from the affected span to determine probable collapse mechanisms. We then provided ODOT with documentation detailing the initial cause and the sequence of events leading up to the bridge collapse. To answer the question of whether this could happen to other bridges, M&M completed a statewide vessel collision vulnerability study. This study included structural and risk analyses for 12 bridge crossings, including vessel and waterway data collection, and vessel collision load calculations. As a result, our technical staff provided ODOT with recommendations for bridge protection systems and accident prevention measures. ODOT has remained proactive in preventing a repeat of the Webbers Falls incident. As active partners, M&M designed pier protection systems for four of the 12 study area bridges.

Bridge Geometry
US-64 Bridge, Sequoyah and Sebastian Counties
Length of Main Span 340 feet
Total Project Length 3,087 feet
I-40 Bridge, Muskogee & Sequoyah Counties
Length of Main Span 330 feet
Total Project Length 2,003 feet
SH-100 Bridge, Muskogee and Sequoyah Counties
Length of Main Span 334 feet
Total Project Length 1,928 feet
SH-51 Bridges, Wagoner County
Length of Main Span 211 feet
Total Project Length 788 feet
US-59 Bridge, LeFlore and Sequoyah Counties
Length of Main Span 350 feet
Total Project Length 1,877 feet