Date of Award

Summer 8-2022

Access Type

Thesis - Open Access

Degree Name

Master of Science in Civil Engineering

Department

Civil Engineering

Committee Chair

Jeff Brown

First Committee Member

Jeff Brown

Second Committee Member

Dan Su

Third Committee Member

Ghada Ellithy

Abstract

The Florida Department of Transportation (FDOT) is currently pushing toward the use of flexible fillers (FF) in new post-tensioned (PT) bridges. Flexible fillers have several advantages compared to the currently used cementitious grouts (CG) and can offer longer-lasting structures by providing better corrosion protection and allowing for replaceable tendons, which reduces the overall maintenance costs over the structure’s lifespan. Due to these fillers being used in new bridges, FDOT needs effective nondestructive evaluation (NDE) methods to employ in their biennial inspections. There are currently numerous NDE methods available to inspectors that have been used to identify defects in PT bridges that use CG, but the NDE methods identified in this study are specifically for PT bridges that use FFs. These methods are Visual Inspections, Radiography, and Thermoelasticity. After an extensive literature review, these methods became the most promising and feasible to perform given the resources available. It was found that visual inspections and radiography are both highly effective methods in evaluating these bridges, whereas thermoelasticity was not as successful. Visual examinations are currently performed on all bridge inspections, but it is important to identify visual indicators that are unique to PT bridges that use FF. Radiography is also an effective method in identifying defects, however there are some major drawbacks, such as the price and accessibility to the internal components of the bridge. Thermoelasticity also seemed like a promising NDE method due to its success in the mining industry, but after completing tests in the lab it was found that the results were inconsistent and inconclusive, therefore this method would not be beneficial to employ in the field. Based on the testing performed in this study, visual inspections and radiography are both recommended methods to use in future bridge inspections and more research should be conducted to create standardized inspection procedures for inspectors.

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