Tsunamis are series of ocean waves caused by disturbances under the ocean, most commonly earthquakes. Once caused, the water is displaced and radiates in fast moving waves. Tsunamis can damage property, cause loss of life, and environmental impacts through flooding and debris. Safety tips include being alert for warnings in coastal areas, having an evacuation plan to higher ground, and not staying near the shore to watch a tsunami come in. Tsunami waves can overload building walls, windows, doors and structural elements, potentially causing complete building failure, especially for structures directly facing the ocean. Designing tsunami resistant structures considers open first floors, deep foundations, orientation away from the shoreline, and continuous steel framing

1. TSUNAMI
ENGR. MD. SHAMIM AHMED
LECTURER
DEPT. OF CIVIL ENGINEERING
SOUTHERN UNIVERSITY BANGLADESH

2. WHAT IS TSUNAMI?
A tsunami is a series of ocean waves that are generated by large
movements or other disturbances on the ocean's floor.
Such disturbances include volcanic eruptions, landslides and
underwater explosions, but earthquakes are the most common cause.
The word Tsunami is derived from a Japanese word translating into
“harbor waves”.

3. CAUSES OF TSUNAMI
Earthquake
Volcanic
eruption
Underwater
explosions
Meteorite
impacts

4. CAUSES OF TSUNAMI
Tsunamis are also called a seismic sea waves because they are most
commonly caused by earthquakes.
In order for an earthquake to cause a tsunami, it must occur below the
ocean's surface or near the ocean and be a magnitude large enough to
cause disturbances on the sea floor. Once the earthquake or other
underwater disturbance occurs, the water surrounding the disturbance is
displaced and radiates away from the initial source of the disturbance (i.e.
the epicenter in an earthquake) in a series of fast moving waves. cause.

5. EFFECTS OF TSUNAMI
 Damaging property
 Loss of life
 Flooding and contamination of drinking water
 Environmental impacts
 Solid wastes and disaster debris
 Radiation from nuclear plants
 Psychological effects
 Post Traumatic Stress Disorder (PTSD)

6. TSUNAMI PRECAUTIONS – SAFETY TIPS
 When in coastal areas, stay alert for tsunami warnings.
 Plan an evacuation route that leads to higher ground.
 Know the warning signs of a tsunami: rapidly rising or falling coastal
waters and rumblings of an offshore earthquake.
 Never stay near shore to watch a tsunami come in.
 A tsunami is a series of waves. Do not return to an affected coastal area
until authorities say it is safe.

7. WHAT CAUSES BUILDINGS TO FAIL DURING TSUNAMI?
 When a building stands in the path of the wave, the wall
facing it tends to block the water, and the pressure here
Increases.
 It can overload walls, window, doors, columns or
bracing systems, or push buildings completely
over.
 Later on the water will swirl out again, loading
the other side of the building.
 Water just 7 ft. deep will have pressure of 450
pounds per sq. ft., much more than any normal structure can withstand.

8.  RCC structures instead of wood, even though wood construction is more resilient to
earthquake.
 RCC or steel-frame structures are recommended for vertical evacuation structures.
 Multi-storied structures, with the first floor being open (on stilts) or breakaway so the major
force of water can move through. Rising water will do less damage if it can flow underneath
the structure. This design is contrary to seismic practice, which makes this recommendation
complicated and site specific.
 Construct deep foundations, braced at the footings.
 As much as possible leave vegetation and reefs intact. They won’t stop tsunami waves, but
they can slow them down.
 Orient the building at an angle to the shoreline. Walls that directly face the ocean will suffer
more damage.
 Use continuous steel framing, strong enough to resist hurricane-force winds.
DESIGN CONSIDERATIONS FOR TSUNAMI RESISTANT STRUCTURES

9. THANK YOU