Abstract: In 2023, Jacobs Engineering Group Inc. was hired to design a fishery harbor in Johnson Bay, ME. The main objective of the design was to serve a tranquil harbor for 35 fishing boats while providing a safe harbor under 100-year wave conditions. The other constraint of the project was to come up with a design that would not only serve the intended function but also meet the strict budget limitation that was granted a few years prior during the feasibility stage. The structure comprises a rubble-mound breakwater, transitioning into a pile-supported high-level platform with a wave screen on the seaward side. The project site is located along the Bay of Fundy, which is known for achieving the largest tidal variation of any location in the world at its northern reaches. At the project site, the tidal range is approximately 22 ft between Mean Higher High Water (MHHW) and Mean Lower Low Water (MLLW). Due to the unique wave and water level characteristics of the project site, it was determined that a three-dimensional (3D) hydraulic physical model of the structure would need to be tested to ensure that the breakwater trunk and its transition to high-level platform withstands design criteria for rock stability and wave overtopping. The physical model's objective was to verify the pier's structural integrity, identify any weak points, ensure wave overtopping was within acceptable levels, and determine whether the design could be optimized to reduce the client's project costs. Proposals to conduct physical model tests were collected from several internationally well-known laboratories. Subsequently, the proposals were evaluated based on technical and cost merits and scored to determine the best laboratory to execute the work. Once the laboratory was selected, detailed model drawings were developed and shared with the laboratory during a workshop. With limited guidance from a senior engineer, the author supervised the model testing for the base layout and assessed the results to verify that the structure fulfilled the design damage criteria. The physical model testing included cases corresponding to the 1-,10-,50-, and 100-year return period water levels and waves. The 100-year wave case was run for extreme high and low water levels to ensure structural stability at the crest and the breakwater toe was sound. The 3D physical model test results showed that the structure experienced damage well within the acceptable limits, and wave overtopping was minimal relative to the design criteria. Therefore, it was optimized to reduce the client's construction costs. The poster presentation discusses these findings with damage assessment and results with graphical illustrations.
Please describe the young professional’s contributions to the project, including but not limited to, building a model, writing a technical report, performing calculations, construction administration and observation tasks, and any aspects of design. (500 words max): The contributions of the presenter to the project include: • Performing extreme value analysis of water levels and wind speeds to determine various return period extreme events • Investigation into local sea level rise • Performing Spectral Wave Modeling to determine extreme wave conditions near the site for both high and low water scenarios • Performing Boussinesq Wave Modeling to determine wave tranquility behind the breakwater during extreme storm events • Evaluating design alternatives for reducing costs, such as change in structure type and length • Performing Goda and Sainflou wave pressure force calculations • Performing wave overtopping calculations according to Eurotop 2018 • Assisting with Sediment Transport Modeling to determine sedimentation within the harbor • Writing Design Criteria report • Writing numerical modeling technical memorandum • Oversight of physical model testing.
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