Date of Award

January 2016

Degree Type


Degree Name

Doctor of Philosophy (PhD)


Civil Engineering

First Advisor

Samuel Labi

Committee Member 1

Kumares C. Sinha

Committee Member 2

Jon D. Fricker

Committee Member 3

Fred L. Mannering

Committee Member 4

Thomas Morin


In an era of increasing demand and loading, aging infrastructure, and funding shortfalls, infrastructure agencies continue to seek cost-effective solutions to persistent and pervasive questions regarding the upkeep of their physical assets. One such question is the appropriateness of the current fixed condition thresholds used at several agencies for rehabilitation timing purposes, whether there is the possibility of having flexible rather than fixed thresholds, and determining what these thresholds should be. A related question is how these flexible thresholds may vary, depending on the objectives of the decision maker, the relative weight of agency and user costs, and the form of expression of the life-cycle cost associated with the candidate rehabilitation schedules. Fortunately, a number of past researchers have developed inputs that are valuable for addressing this issue. Also, there exists data from in-service infrastructure that could be used to test the hypotheses regarding the sensitivity of the optimal schedules.