Work

Investigations on the development of hybrid mound breakwaters for tsunami defense

Year: 2025

Type: article

Abstract: • Traditional rubble mound breakwaters experienced significant damage during tsunami overflow, highlighting the need for improved structural integrity and resilience. • The developed hybrid mound breakwater enhanced structural stability and resilience against tsunamis. • The hybrid model demonstrated substantial reductions in structural damage, lateral shift, and subsidence, indicating improved safety and reliability in coastal defense. • The hybrid mound breakwater reduced the development of higher pore water pressure in the seabed during tsunamis. Tsunamis significantly damage coastal infrastructure and lives, resulting in extensive economic implications. Despite the global adoption of breakwaters as a primary coastal defence measure, it was observed that the structural integrity of several of these breakwaters was compromised during past tsunamis. The present study addresses these vulnerabilities of breakwaters by particularly focusing on the most commonly adopted rubble mound type breakwater. Further, this study introduces a novel technique in order to enhance the reliability of these structures by mitigating the tsunami induced failure mechanisms. In the novel technique, wrap-faced geogrids are implemented to reinforce the rubble mound without compromising the breakwater functionality in dissipating the incident wave energy through transmission. A comprehensive evaluation was carried out, including tsunami overflow tests, analytical assessments, and numerical simulations, to ascertain the effectiveness of the novel hybrid mound breakwater. The findings indicate that the developed hybrid mound breakwater withstood level 1 tsunamis with a 96.7 % reduction in settlement. One of the critical failure mechanism of breakwaters observed during past tsunamis was due to the seepage induced scouring of the foundation. The hybrid mound breakwater showcased a 42.37 % reduction in the foundation pore water pressure during tsunami by incorporating cut off walls. The numerical simulations also reconfirmed the enhanced performance of hybrid mound breakwater to protect the coasts from future tsunamis.

Source: Applied Ocean Research

DOI: 10.1016/j.apor.2025.104489

Authors: Manu K Sajan, Babloo Chaudhary, Akarsh P K, Babita Sah

Institution: National Institute of Technology Karnataka

Language: English

Topic: Earthquake and Tsunami Effects

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $2,950