||Taiwan is the island which is well known for its distinctive topography features. The central mountain range bisects the land from north to south resulting in most rivers have short courses and rapid streams. As a result, the scour effect could be seem as a critical problem for the bridge structure as the scale of natural disasters increase. The growing amount of bridge failure events in Taiwan due to typhoons and floods in recent years causing the public pay more and more attention towards the bridge safety under natural disaster, and the government and related organization also put a lot of efforts on such problem. This dissertation applies five kinds of sensing units which is based on the same sensing mechanism of developed scour monitoring system to laboratory experiments. Sensing units includes micro-electro-mechanical systems based pressure sensors, vibration-based detection sensors, floating ball, inner camera and handheld camera. The main purpose of this research is to verify the feasibility of developed monitoring system and to establish a warning benchmark by conducting the various test using reduced scale bridge structure model in laboratory.
The feasibility of the developed monitoring system has been verified in laboratory by several experiments. The scour depth measurement by using accelerometers and the floating ball have been successfully applied to experiments, and it could be observed and confirmed that the scour depth can be regarded as the major parameter for the safety evaluation of caisson foundation bridge. Modes of scour failure for bridge structure are complex with many uncertainties, but the proposed sensing mechanisms for scour early warning could be achieved.