-
European Council for the village and small town ECOVAST
Russian Committee for the village and small town-ECOVAST
 

 

   

.
Article of interest about Haiti construction

Flawed Building Likely a Big Element
By HENRY FOUNTAIN http://topics.nytimes.com/top/reference/timestopics/people/f/henry_fountain/index.html?inline=nyt-per
Published: January 13, 2010

Engineers and architects who have worked in or visited Haiti
http://topics.nytimes.com/top/news/international/countriesandterritories/haiti/index.html?inline=nyt-geo
say that substandard design, inadequate materials and shoddy construction practices likely contributed to the collapse of many buildings in the earthquake that struck Tuesday.

http://www.nytimes.com/2010/01/14/world/americas/14construction.html Cameron Sinclair, executive director of Architecture for Humanity http://www.architectureforhumanity.org, a nonprofit design group based in San Francisco, said he was horrified when he visited Port-au-Prince and Gonaives last October to assess the quality of construction there.

Mr. Sinclair said that design and construction were far worse than in other developing countries he had visited. In Haiti, most if not all of the buildings have major engineering flaws, he said.

Most houses and other structures are built of poured concrete or block, there being very little lumber available due to mass deforestation, said Alan Dooley, a Nashville architect who designed a medical clinic, built of reinforced concrete, in Petite Riviere de Nippes, a fishing village 50 miles west of Port-au-Prince.

Concrete is very expensive much of the cement for it comes from the United States, Mr. Dooley said so some contractors cut corners by adding more sand to the mix. The result is a structurally weaker material that deteriorates rapidly, he said. Steel reinforcing bar is also expensive, he said, so there is a tendency to use less of it with the concrete.

Building codes are limited or nonexistent, so columns and other elements made from concrete are often relatively thin, designed without proper margins of safety. We would double the design strength, just to give it a factor of safety, Mr. Dooley said, referring to practices in the United States. There theyd design it to what it would hold.

Concrete blocks are often substandard too, said Peter Haas, executive director of Appropriate Infrastructure Development Group http://www.aidg.org , a nonprofit organization that is working on several projects in Haiti. Many of them are made in small batches at peoples homes, and the quality can vary. When youre buying blocks at the store you really have no idea of where theyre from, Mr. Haas said. And all it takes is for the block that was made at home to collapse.

When builders in Haiti do take disasters into account in their designs, their most recent experience has been with hurricanes http://topics.nytimes.com/top/reference/timestopics/subjects/h/hurricanes_and_tropical_storms/index.html?inline=nyt-classifier the last major earthquake having occurred two centuries ago. Newer construction has been developed to withstand hurricanes, not earthquakes, said John McAslan, a London architect who has studied Haitian buildings, working with the Clinton Global Initiative http://www.clintonglobalinitiative.org. If you engineer for one youre not necessarily covering the other.

Mr. Dooley said that his original design for the medical clinic called for a steel roof, but that was changed to a reinforced concrete one to better withstand hurricane-force winds. The building survived the earthquake with apparently little damage, he said.

But many other concrete roofs presumably collapsed, adding to the loss of life. Mr. Sinclair said he had seen houses where builders put concrete roofs on top of low-grade blocks. Then it just pancakes, he said.


 

  . .