Vibration testing of cracked reinforced concrete beams under sustained load
University of New Brunswick
In this thesis, topics relevant to vibration testing of cracked reinforced concrete beams are discussed. First, the effective moment of inertia is obtained from different formulas. Then, an analytical model based on Euler Bernoulli beam and differential transformation method (DTM) is presented. After that, for concrete beams that had been preloaded and subjected to a sustained load (less than the preload) for a duration of 8 years we developed a finite element model in ABAQUS with appropriate modelling assumptions. The damage plasticity model is used as a material property for numerical modelling. In this stage, parameters such as different mesh sizes and element types were studied. Subsequently, different vibration tests are conducted on the physical model, and the dynamic characteristics of the cracked concrete beams are successfully extracted using the operational modal analysis (OMA). It is shown that the results of OMA are not mostly affected by excitation types. The frequencies of concrete beams under cyclic load are successfully obtained. Several discrepancies and inconsistencies were observed in the experimental study results and the numerical and analytical models. However, due to the university closure because of the COVID-19 pandemic, the tests could not be repeated to validate the data. Therefore, the author recommends the presented experimental results in this thesis to be validated prior to any further analysis.