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This experimental project investigated the debris accumulation in front of structures during tsunamis (debris damming), which leads to an increase in the forces imposed by tsunami flow on structures. The study was conducted through the construction of a 1:20 geometric scale physical model. Tsunami-like waves were generated over an idealized slope and transported different shapes of multi-debris, representing shipping containers, over the flat test section to measure debris loadings on elevated column structures. The experiment optically measured the debris impact and damming process, along with the corresponding loads on the entire column structure using a Force Balance Plate and separately on an individual column in the front row using a load cell. This unique data set will help to understand the impact of various factors on debris-driven damming loads, including wave characteristics, specimen configurations, and debris shapes. This data will also help to develop and validate numerical models that predict the motion and dynamics of floating debris during extreme coastal events. This project is the outcome of “Collaborative Research: Experimental Quantification of Tsunami-driven Debris Damming on Structures” with collaborators from the University of Hawaii at Manoa, Louisiana State University, and Oregon State University.
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Tsunami debris motion and loads in a scaled port setting: Comparative analysis of three state-of-the-art numerical methods against experiments
We present an international comparative analysis of simulated 3D tsunami debris hazards, applying three state-of-the-art numerical methods: the Material Point Method (MPM, ClaymoreUW, multi-GPU), Smoothed Particle Hydrodynamics (SPH, DualSPHysics, GPU), and Eulerian grid-based computational fluid dynamics (Simcenter STAR-CCM+, multi-CPU/GPU). Three teams, two from the United States and one from Germany, apply their unique expertise to shed light on the state of advanced tsunami debris modeling in both open source and professional software. A mutually accepted and meaningful benchmark is set as 1:40 Froude scale model experiments of shipping containers mobilized into and amidst a port setting with simplified and generic structures, closely related to the seminal Tohoku 2011 tsunami case histories which majorly affected seaports. A sophisticated wave flume at Waseda University in Tokyo, Japan, hosted the experiments as reported by Goseberget al. (2016b). Across dozens of trials, an elongated vacuum-chamber wave surges and spills over a generic harbor apron, mobilizing 3–6 hollow debris-modeling sea containers-, in 1–2 vertical layers against friction. One to two rows of 5 square obstacles are placed upstream or downstream of the debris, with widths and gaps of 0.66x and 2.2x of debris length, respectively. The work reports and compares results on the long wave generation from a vacuum-controlled tsunami wave maker, longitudinal displacement of debris forward and back, lateral spreading angle of debris, interactions of stacked debris, and impact forces measured with debris accelerometers and/or obstacle load-cells. Each team writes a foreword on their digital twin model, which are all open-sourced. Then, preliminary statistical analysis contrasts simulations originating off different numerical methods, and simulations with experiments. Afterward, team’s give value propositions for their numerical tool. Finally, a transparent cross-interrogation of results highlights the strengths of each respective method.
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- Award ID(s):
- 2131111
- PAR ID:
- 10586366
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Coastal engineering
- Volume:
- 197
- Issue:
- 2025
- ISSN:
- 0378-3839
- Subject(s) / Keyword(s):
- STAR-CCM+ Debris–fluid–structure interaction
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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