1

LESSONS FROM THE HAITI EARTHQUAKE

Department of Civil and Environmental Engineering Tokyo Institute of Technology

Yoshida Mayumi Kim Hyeong Tae Nakaya Tomoyuki Nguyen Manh Viet

Contents2

Construction Standards Buildings in Haiti Before the earthquake happened The mechanism of Haiti Earthquake The absence of surface rupture Building pressure Conclusions

Construction Standards Buildings in Haiti3

Typical concrete details show:→ Poor quality concrete, lack of consolidation→ Weak cement mixed with dirty or salty sand , act…

No building code in Haiti, no licensing requirements for architects, engineers, or contractors

Seismic design is not included in the engineering curriculum in Haiti

　

Before the earthquake happened4

Haiti government has not supervised construction and not oblivious to Haiti’s plate boundary location

Seismologists have written and spoken extensively about the possibility of damaging earthquakes occurring on the part of Caribbean plate boundary

The mechanism of Haiti Earthquake5

The earthquake occurred on the Enriquillo Fault(strike-slip fault).

Caribbean Plate moves at 12 millimeters eastward and North American Plate 8 millimeters westward.

The fault slips an average of 8 millimeters a year.

In 1751 and 1770, big earthquakes happened on the Enriquillo Fault and demolished the city, Port-au-Prince.

Since 1770, big earthquake hadn’t happened.

Caribbean Plate slipped about 2 meters on January 12.

The mechanism of Haiti Earthquake6

The absence of surface rupture7

No rupture of the surface wasn’t found around the epicenter above the Plate-boundary Fault.

The rupture started more than 8 kilometers underground, but ended at least 2 kilometers below the surface.

There are several precedents : Loma Prieta earthquake (1989), Bhuj earthquake (2001)

Loma Prieta earthquake

Bhuj earthquake

The absence of surface rupture8

It means that elastic energy is still stored in the uppermost few kilometers of the fault.This energy will be released either to the severe future earthquake or a seismic creep.There are surface scars, so it means larger earthquakes had happened before Haiti earthquake 2010.Many thousands will have occurred before historical records began with the arrival of Columbus.

Building pressure9

Serious problems come out because of the Haiti earthquake.

<Structure of buildings> Elementary engineering guidelines for earthquakes resistance in

crucial civil structures have been unfamiliar concepts in Haiti. Example : About 80% of all schools collapsed in the Port-au-Prince area. In

addition, police stations and jails were a similar situation.

<Urban earthquakes > Urban earthquakes have a risk that kills many people just

once. A main cause of a swell in damage is collapsed building. Urban earthquakes also bring a huge financial burden to the

world. Example: US$2.5billion of financial aid in the case of the Haiti earthquake.

Conclusions10

Therefore, earthquake engineers insists the importance of training constructors, the need to introduce an adequate building code and a cadre of building inspectors.

If minimal construction guidelines are required by law in all world’s cities, the future global burden and the toll of local earthquakes could be reduced.

Community leaders responsible for safety of their citizens need to act on seismologists ’ forecasts of future earthquake.