About Us

- Terms of Refrence of WG53 -

Recommendations with regard tothe design and construction of maritime structures in tsunami prone areas
Terms of Reference

1. Historical background - Definition of the problem

The Indian Ocean Earthquake Tsunami which occurred December 26, 2004 due to a huge subduction zone earthquake off the west coast of Sumatra caused devastating damage including casualties numbering 300 thousand. Ports in the area also suffered tremendous damage.

Field investigations conducted by many researchers revealed the damage differed greatly depending on the topography and other conditions in the coastal zones. The damage was reduced by the presence of coastal reefs and sand dunes, as well as coastal defense facilities including port facilities (breakwaters and seawalls). On the other hand, many ships in ports were washed ashore, causing damage to the on-land facilities. This suggests that containers and timber in ports can become very harmful objects if washed ashore.

For protection against tsunami damage, it is essential to prepare in advance based on thorough understanding of not only tsunami damage in ports but also the positive and negative effects on areas surrounding ports.

2. Objective of the study

Once a tsunami disaster occurs, it can be devastating. However, since the probability of its occurrence is very low, only a very limited number of port engineers and administrative personnel have had actual experience with tsunami disasters and therefore their knowledge of tsunamis is very limited.

The objective of the study is to disseminate knowledge about tsunamis to port engineers and administrators. We summarize the fundamental mechanics of tsunamis highlighting comparison with wind waves and describe the damage inflicted upon harbor and coastal structures Simulations of tsunami generation and propagation are discussed, and the anti-tsunami design of port and coastal structures is presented.

3. Review of earlier reports

PIANC has not published reports on tsunamis. In Japan, the Technical Standard for Port and Harbor Facilities in Japan is being revised and the Design Manual for Coastal Facilities will soon be published.

4. Matters to be investigated

The principal aim of this study is to summarize existing knowledge of tsunamis; information from new surveys and investigations is limited. The tsunami disasters experienced in the member countries should be clarified, including the Indian Ocean Earthquake Tsunami.

5. Approach

Each member of the WG will summarize the accumulated knowledge on tsunamis in their country. The WG meetings will be held in the countries which expect tsunami disasters in the future, especially countries around the Indian Ocean.

6. Suggested final report of the Working Group

Contents  (tentative)

  1. Introduction
  2. Definition of tsunami and tsunami observation
  3. Generation, propagation and run-up of tsunami and numerical simulations
  4. Tsunami forces and failure of structures
  5. Recent tsunami damages to port and coastal facilities
  6. Risk of drifting ships and containers
  7. Damage reduction by port and coastal facilities
  8. Anti-tsunami considerations for designing port and coastal structures
  9. Countermeasures against tsunamis in ports
  10. Concluding remarks

7. Desirable disciplines of the members of the Working Group

  • Tsunami researchers
  • Port Engineers and Administrators in whose countries the risk of tsunami disaster exists, especially countries around the Indian Ocean.

8. Relevance for countries in transition

Especially for countries in transition in tsunami prone areas, it is important to design port structures in such a way that after a tsunami the port infrastructure is as soon as possible operational to allow international relief operations.