Semester of Graduation
Fall 2025
Degree Type
Dissertation/Thesis
Degree Name
Master of Science in Civil Engineering
Department
Department of Civil and Environmental Engineering
Committee Chair/First Advisor
Mohammad Jonaidi
Second Advisor
Tien Yee
Third Advisor
Metin Oguzmert
Abstract
Bridge fires are rare events that can rapidly degrade bridge components and disrupt transportation networks. This thesis develops practical post-fire triage inspection procedures for steel and concrete bridge elements based on a synthesis of historical bridge fire trends, ignition scenarios, thermal demands, and common fire-related defects. It also reviews temperature-based damage-state frameworks that can support rapid triage decisions. Further, it evaluates non-destructive tests for estimating residual compressive strength of fire-damaged concrete. Laboratory testing used 4x8 inch concrete cylinders exposed to nominal temperatures between 400 and 1000°C for durations up to 120 minutes. Rebound hammer readings, ultrasonic pulse velocity, and maximum crack width were measured before and after heating, followed by compressive strength testing. Regression models were developed to relate the percentage of remaining compressive strength to each indicator. Multifactor linear regression was used to relate the percentage remaining compressive strength to the percent change in rebound hammer values, the percent change in ultrasonic pulse velocity, and maximum crack width. Testing found that the two-factor model using percent change in rebound hammer and ultrasonic pulse velocity provided the best balance of simplicity and predictive performance. This thesis concludes with recommendations for further model development and validation, image-based damage mapping and assessment, and investigation of carbonation as a driver of age-related defects.