The Technical Reflections from Kevin that I included in the previous blog post started out as an email that Kevin put together late one night and sent to me, as well as to some coworkers both here in Canada and at the Colorado Springs office. Well, someone forwarded it to someone else, who forwarded it to someone else . . . and it eventually ended up in the hands of an adjunct faculty of city planning and urban affairs at Boston University, who asked if he could post it on his blog (check out the April 5, 2010 post).
It’s one thing to be pulling together in-house reflections of a situation for eMi and our personal blog – quite another for these reflections to be made public, so there was a bit of a flurry of activity as Kevin confirmed with his team members and some others at eMi that his assessment of the situation was accurate. Here’s the comments of Glenn Gilbert, one of Kevin’s Haiti team members, that rounds out Kevin’s technical reflections:
I would characterize the cause of the extent of failure as: traditional Haitian construction is heavy, stiff and brittle, and does not account for lateral forces. Inattention to construction detail compounds these weaknesses.
The main function of column stirrups is to prevent the buckling of the principle reinforcing. Once the reinforcing buckles, the concrete has little capacity to resist bending and compression forces.
I can think of two other construction detail deficiencies we saw: reinforced masonry for which the grout wasn’t consolidated in the cells, and the “epoxy grouted dowel” in the masonry column on the porch at EFCA. I think the epoxy grouted dowel is significant because the shows the lack of understanding on the part of the part of the Haitian workers and the need for supervision and education.
I think the key to better construction in high seismic areas of the third world is reinforced masonry walls, better quality block and construction education. I think you could leave the column construction as it is if the walls were designed correctly. We could suggest limiting traditional construction to two stories, and the roof to be wood framed.