Speaking

Four steel bridges located on a remote stretch of Interstate 15 in northern Arizona are currently the subject of a study involving visual inspection, load testing, long term instrumentation and remote health monitoring. The project is being funded by the Arizona Department of Transportation (ADOT) through a FHWA Accelerated Innovation Deployment Grant. The purpose of the project is to utilize state-of-the-art structure health monitoring technologies to provide information that will ensure the safety of the traveling public and provide better information to assist ADOT in short and long term decision making about these significant bridges. The steel bridges currently exhibit widespread fatigue cracking.

The presentation will provide a status update on the project which began in 2016 and will continue through 2018. The discussion also will include a history of the bridges, visual inspection efforts and documentation, analytical modeling work, load testing and instrumentation, instrumentation selection, fatigue analysis, site challenges, and the long term monitoring plan.

Beneath the surface of visibly sound concrete bridges lies a potentially significant disease that can cause corrosion and deterioration. If left untreated, it can shorten the service life and reduce the load carrying capacity of post-tensioned (PT) bridges. PT bridges built before the early 2000s are susceptible to structural deficiencies. This is due to the poor grouting materials and construction procedures that were utilized at that time. Accessing and determining the condition of bridge tendons – the primary structural element on PT structures – requires a team experienced with the most current testing procedures.

Without the knowledge of what factors are driving deterioration, the solution may not be effective. The goal is not just to identify symptoms, but to determine, treat and cure the underlying disease.

This presentation will discuss two case studies in detail which this team of experts, who have collaborated for more than 10 years, have diagnosed and repaired post-tensioned bridges. Case studies include the inspection, testing, results and conclusions of the Mid Bay Bridge in Florida and the Cline Avenue Bridge in Indiana. With each of these case studies presenters will review factors that will help identify the culprits of corrosion that can drive infrastructure deterioration and steps to take to determine if a repair program and remediation is right for your agency.

This session will be co-presented by B&N’s Dallas Montgomery and Sivaraman Venugopalan from Siva Corrosion Services, Inc. (SCS).

Occasionally, understrength or distressed and deteriorated structural details are identified during regular bridge inspection activities. In extreme cases, these problems could compromise the structural integrity of the entire bridge. When inspectors spot potential problems in the field, additional load rating and structural analysis is performed.

This presentation will focus on a case study of a recent project located in Tulsa, Oklahoma where our team of bridge inspectors identified understrength seated hinge details on numerous concrete box girder bridges in a complex urban interchange. The presentation will include a review of the means and methods used to develop the repair concepts for replacing the hinges and avoiding a costly total replacement, while minimizing the impact to the traveling public during bridge rehab work.