One of the most important problems facing structural and design engineers is the analysis of dynamic behavior of bridges subjected to moving loads. In this thesis, the DET formulation for moving point mass was extended to Timoshenko beams subjected to distributed moving masses. Also, vibration analysis of beams with open and breathing cracks subjected to moving masses was investigated. The differences between two models of crack, namely open and breathing cracks, are investigated and shown that the breathing crack model shows less deflection in compare with the open crack model. Being lightweight, thin and easy to bond on the damaged structure, the piezoelectric patch can be designed with minimum adverse effect on the global behaviour of the structure. This thesis extends the use of piezoelectric patches for the repair of cracked Timoshenko beam subjected to a moving mass using transfer matrix method. Based on Timoshenko beam theory, the dynamic response of an elastically connected multiple-beam system was also investigated. The identical prismatic beams are assumed to be parallel and connected by a finite number of springs. Also, the chaotic response of a Timoshenko beam subjected to moving masses with a non-ideal support in between was analysed. Key Words: Timoshenko beam; Moving ma Breathing crack; Chaos; Piezoelectric; Assumed modes.
