Date of Defense
4-6-2026 3:00 PM
Location
F1-1117
Document Type
Thesis Defense
Degree Name
Master of Science in Civil Engineering (MSCE)
College
COE
Department
Civil and Environmental Engineering
Keywords
local Froude number, control Froude number, super-critical flow, Manning`s roughness coefficient, numerical modelling, Acropora corals, tsunami mitigation
Abstract
This thesis investigates the role of coral reefs as nature-based tsunami protection systems for coastlines in the United Arab Emirates (UAE). The study is significant because the UAE is located near the seismically active Makran Subduction Zone in the Arabian Sea, which may generate tsunami hazards. The research provides a quantitative assessment of how coral reef morphology, particularly reef width and depth, influences tsunami wave attenuation, flow velocity, flow depth, roughness, and bed shear stress.
The study used a multi-phase methodology combining literature review, laboratory experiments, and numerical modelling. Flume experiments were conducted at UAEU using high-fidelity 3D-printed Acropora coral models. These experiments examined supercritical flow conditions with Froude numbers of 1.5, 1.9, and 2.5, representing high-energy tsunami inundation over submerged reef platforms. The results were used to develop empirical models for estimating Manning’s roughness coefficient under tsunami flow conditions.
Numerical simulations were then carried out using shallow water equations to model 12 tsunami scenarios across three tsunami periods: 5, 10, and 20 minutes. Four reef geometries were tested: narrow shallow reefs, wide shallow reefs, narrow deep reefs, and wide deep reefs. The findings showed that wide shallow reefs were the most effective, reducing coastal flow velocity by up to 24% and flow depth by up to 12%. Shallow reefs generated strong tsunami-reef interactions, with bed shear stresses ranging from 700 to 5000 N/m², while deep reefs showed minimal attenuation and stresses below 200 N/m².
Overall, the thesis confirms that reef morphology, especially the combination of wide reef width and shallow depth, is the main factor controlling tsunami mitigation. The findings support coral reef conservation and restoration as sustainable, ecologically positive alternatives to traditional coastal defenses.
Included in
NUMERICAL ASSESSMENT ON THE USE OF STRUCTURED CORAL REEFS TO MITIGATE TSUNAMIS
F1-1117
This thesis investigates the role of coral reefs as nature-based tsunami protection systems for coastlines in the United Arab Emirates (UAE). The study is significant because the UAE is located near the seismically active Makran Subduction Zone in the Arabian Sea, which may generate tsunami hazards. The research provides a quantitative assessment of how coral reef morphology, particularly reef width and depth, influences tsunami wave attenuation, flow velocity, flow depth, roughness, and bed shear stress.
The study used a multi-phase methodology combining literature review, laboratory experiments, and numerical modelling. Flume experiments were conducted at UAEU using high-fidelity 3D-printed Acropora coral models. These experiments examined supercritical flow conditions with Froude numbers of 1.5, 1.9, and 2.5, representing high-energy tsunami inundation over submerged reef platforms. The results were used to develop empirical models for estimating Manning’s roughness coefficient under tsunami flow conditions.
Numerical simulations were then carried out using shallow water equations to model 12 tsunami scenarios across three tsunami periods: 5, 10, and 20 minutes. Four reef geometries were tested: narrow shallow reefs, wide shallow reefs, narrow deep reefs, and wide deep reefs. The findings showed that wide shallow reefs were the most effective, reducing coastal flow velocity by up to 24% and flow depth by up to 12%. Shallow reefs generated strong tsunami-reef interactions, with bed shear stresses ranging from 700 to 5000 N/m², while deep reefs showed minimal attenuation and stresses below 200 N/m².
Overall, the thesis confirms that reef morphology, especially the combination of wide reef width and shallow depth, is the main factor controlling tsunami mitigation. The findings support coral reef conservation and restoration as sustainable, ecologically positive alternatives to traditional coastal defenses.