Tsunami-driven debris hazard assessment at a coastal community: Focusing on shipping container debris hazards at Honolulu Harbor, Hawaii

A framework combining a tsunami flow model and debris (large floating object) transport model was developed to evaluate the kinematics of multiple debris and sequential hazards in a coastal community. We derive the analytic solution of the semi-analytic model of debris transportation, and adapt to evaluate the impact of tsunami-driven debris at Honolulu Harbor, Hawaii as a case study by simulating the motion of 2500 shipping containers under a hypothetical 2500-year tsunami event. The study provides a framework for assessing tsunami-driven debris hazards in a coastal community by introducing new types of intensity measures for tsunami-driven debris hazards. The final debris dislocation in the numerical debris transport model was quantitatively compared with the debris impact hazard region of the ASCE 7-22 method. This study introduces new types of hazard maps showing the intensity ratios of the debris dispersion, maximum impact loading, accumulated impact loading, and 5% exceedance impact loading. These new hazard maps characterize the potential impact loadings from debris dispersion on a community scale and display hotspots that show the strong intensity of the hazards from debris. The sensitivity of the new hazard maps based on the debris model parameters is also discussed.

Automated summary

A framework combining tsunami flow model and debris transport model is developed to evaluate the kinematics of multiple debris and sequential hazards in a coastal community. The impact of tsunami-driven debris at Honolulu Harbor, Hawaii is assessed by simulating the motion of 2500 shipping containers under a hypothetical tsunami event. New types of intensity measures for tsunami-driven debris hazards are introduced, and hazard maps showing the potential impact loadings from debris dispersion are presented.