Date of Award


Degree Name

Master of Science in Engineering


Civil and Construction Engineering

First Advisor

Dr. Yufeng Hu

Second Advisor

Dr. Xiaoyun Shao

Third Advisor

Dr. Osama Abudayyeh


Wavelet transform, structural health monitoring, damping ratio, modal properties, damage detection

Access Setting

Masters Thesis-Open Access


Structural Health Monitoring (SHM) is a process of implementing a damage detection strategy in structures to evaluate the condition of existing structures to ensure the safety of users in the future. The changes in the material, geometric and/or structural properties affect structural responses, which can be captured and analyzed for condition assessment. Various vibration-based damage detection algorithms have been developed in the past decades. Among them, the Continuous Wavelet Transform (CWT) gained popularity as an efficient method of signal processing to build a framework to identify model properties and detect damage in structures. In this study, the application of wavelet transform for identification of modal properties and damage detection is presented and numerically verified through verification examples. Then the method is used in two case studies: a single-span steel girder bridge in Holland, Michigan and a cable-stayed bridge in mainland China. The results are compared with those obtained from the Fast Fourier Transform (FFT) method. It is shown that CWT used for output-only identification and damage detection yields good agreement with results from FFT, while CWT can provide time-domain information and FFT cannot.