Scour effect on a single pile and development of corresponding scour monitoring methods

Bridge scour is a major cause of bridge failures and has emerged as a significant concern for bridge engineers. Most previous studies focus on investigating causes of the scour but not on its consequences, in other words, very few studies have been carried out on the response and feature changes of structures due to scour. Therefore, the present paper mainly studied the scour effect on a single pile or pier. A theoretical solution was derived first to obtain the relationship between the scour depth and the pile response, including static and dynamic responses. Since the expression of the solution is tedious and not easy to understand, two examples were used for the demonstration and parametric study. Based on the numerical observation, the present study proposed three possible methods for detecting and monitoring the bridge scour. Finally, a monitoring system using fiber optic sensors was designed and tested in the laboratory to verify the theoretical and numerical results and the monitoring mechanisms.