Guide Specifications for Bridges Vulnerable to Coastal Storms
Overview

The 21st Century brought with it a stark realization for the bridge engineering community: existing structures were overmatched by the alarming number of “storms of the century”. Recent hurricanes publicly demonstrated the vulnerability of bridges to wave forces, storm surges, and storm-borne debris. Hurricane Ivan, in 2004, caused major damage to the I-10 Escambia Bay Bridge in Florida. It knocked out 58 spans, and misaligned another 66 spans that caused the interstate bridge to be closed to traffic in both directions. A year later, Hurricane Katrina inflicted extensive damage to a number of bridges in Louisiana, Mississippi and Alabama. At that time, the LRFD Bridge Design Specifications provided little guidance on coastal storm wave attack. The FHWA and AASHTO were charged with developing a guide specification and retrofit strategies to mitigate damage to bridges subjected to coastal storms.

The FHWA selected a team led by Modjeski and Masters to develop and provide the bridge community with the tools needed to design and assess bridges subject to coastal storms. Our team offered the FHWA a collaboration of both bridge and coastal engineering experts to help them better understand, and address the challenges of designing for, this phenomenon. We developed a practice-oriented specification and retrofit handbook. It was compatible with other AASHTO documents, including the LRFD Bridge Design Specifications. This state-of-the-art document was quickly embraced by AASHTO, the FHWA, and the bridge community.

Bridge Geometry

This state-of-the-art document was quickly embraced by AASHTO, the FHWA, and the bridge community.