Performed a hydraulic and scour analysis of the proposed North Bay Road Bridge in the City of Sunny Isles Beach. The bridge will cross an existing canal with several pier foundations located within the canal. During storm events, the bridge will experience increased water levels and current speeds, which will affect both scour (local erosion around piles) and hydrodynamic forces.
Cummins Cederberg conducted local tide and current measurements for input and calibration of a numerical hydrodynamic model. The current measurements were obtained in strategic locations to develop an understanding of the local flow characteristics.
A statistical analysis was conducted to determine the extreme conditions for various return periods. As severe storms pass the project area, the associated storm surge will generate a rapid increase (and subsequently a decrease) in the water level. During the increase and/or decrease, increased current speeds might be observed at the project site.
A hydrodynamic numerical model was developed to simulate the flow under various conditions. The model was calibrated utilizing the tide and current measurements obtained in the field to ensure the model reflected the actual flow conditions.
Following the calibration, the hydrodynamic flow for various return periods and storm durations was evaluated to determine the design current speed(s). Utilizing the design current speed(s) and water level(s), a scour analysis was conducted. The scour analysis included both the effects of global scour due to contraction in the overall flow area as well as localized pier scour. Subsequently, the hydrodynamic loading was determined.