7.0 hits Haiti?
7.0 hits Haiti?
(OP)
What's goin' on?
Somehow, I never thought of this region as prone to earthquakes of this magnitude. Very strange to me.
Somehow, I never thought of this region as prone to earthquakes of this magnitude. Very strange to me.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask






RE: 7.0 hits Haiti?
See Table 3 on page 341 of:
http://www.jstor.org/stable/4312732?seq=2
and
http://boo
While in the DR for a seismic conference some years ago, the organizers drove us out to see one of the major faults, which had caused 100+ feet of displacement of a creek bank over some relatively short period, creating a big "Z." Truly eye-opening. Then, they showed us what I think they said was the remains of the first church built in the New World, which was destroyed by an earthquake within a few years. (My Spanish is not great, so I won't swear that's what I was told.)
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
Will be a terrible outcome. Lot of the local housing is nothing but concrete with little reinforcing and i'm certain that what is in place is very likely not placed properly. Moreover, the heavy roofs will play havoc with the thin brittle walls in the out-of-plane direction.
Unreinforced masonry/concrete is very popular in these sorts of places similar as it is in Mexico outlying the main city. Or even in South America. No steel or good solid wood construction.
Regards,
![[pipe] pipe](https://www.tipmaster.com/images/pipe.gif)
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
RE: 7.0 hits Haiti?
Dale Grant, a U.S. Geological Survey geophysicist in Golden, Colorado, told Reuters there had been no quakes this large in Haiti for more than 200 years.
"There were two major quakes there in 1751 and 1770 but, since then, there has not been a quake of this magnitude," Grant said.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
http:
RE: 7.0 hits Haiti?
The dome of the government center is on the ground, so apparently, the shake was not is the codes or the standards used.
Dick
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
If you go to the USGS website you can click on the seismic hazard for the area of this quake and see that it is in a low to moderate zone. Supposedly, the seismicity jumps up as you go east from there but whoever published that seismic hazard map may be re-thinking that area. Such is the danger of using recorded history to guess at millions of years of geology.
RE: 7.0 hits Haiti?
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: 7.0 hits Haiti?
Ryan Coggins, P.E., S.I.
http://www.linkedin.com/in/ryancoggins
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
To be quite frank, I noticed the same construction in the Cascun area of Mexico 15 years ago. Seemed to be the norm for small masonry buildings of 3 to 4 stories.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
I just saw a report that they are putting the death toll in at least the 1000's and possibly 100k.
Ryan Coggins, P.E., S.I.
http://www.linkedin.com/in/ryancoggins
RE: 7.0 hits Haiti?
It is just depending on the market requirements and politics.
Real codes and enforcement in Haiti is non-existant. Other islands do have much higher requirements and standards, but good masonry construction is the norm.
I look forward to getting there to look at the failures and causes.
Dick
RE: 7.0 hits Haiti?
Moreover, now that the "big one" has technically occurred for them, will this be enough of a political impetus to change the codes and adhere to them? Somehow, with the embedded political corruption there, I don't think so...
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
What I forgot to note in my earlier post is that they don't build with wood and steel or even rebar as it is hard to get and therefore expensive. Hence in most of the Central and South American areas as well as Carribean the material of choice is masonry or adobe.
Regards,
![[pipe] pipe](https://www.tipmaster.com/images/pipe.gif)
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
RE: 7.0 hits Haiti?
Problem is, whether it was a beam or column, there was absolutely no shear or confinement steel. None whatsoever.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
It is absolutely ludicrous and criminal to me that the hospitals, presidential palace and communication facilities have collapsed.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
I heard a number (21) some time ago that seems awful low.
RE: 7.0 hits Haiti?
It is amazing how many successful great multi-million dollar baseball players come out of the eastern side of the island (Dominican Republic) where they have some facilities and a taste for improvement, but that is the local situation that was created.
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
My thoughts and prayers are with all the Haitian people.
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
U.S. committed 100 million and more in the future.
Maybe this will prompt them to shell out cash for other countries BEFORE it happens.
On another note.. I was in the DR last summer and suprisingly almost every building that I say being constructed had rebar sticking out of the unfinished walls. Maybe that's just because it was near the resorts?
Anthony Deramo
American Bridge Company
RE: 7.0 hits Haiti?
I wonder where the US will pull the money from...(borrow from China again?)
Ryan Coggins, P.E., S.I.
http://www.linkedin.com/in/ryancoggins
RE: 7.0 hits Haiti?
I am not real optimistic about the "clean slate" attracting the kind of capital investment it would take to build a new Port-au-Prince. Private charities and other governments will be the main forces. This is very different from the Chicago fire or the SFO earthquake, because outside of those two cities, there was a functioning national economy as a source of capital, along with a middle class, insurance, etc. The earthquake in Haiti will be far harder and slower to recover from.
RE: 7.0 hits Haiti?
It takes time to get the traditions and "kinks" out and to rebuild confidence in an area for rebuilding.
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: 7.0 hits Haiti?
I would like to think that the rebuilding process will spark some kind of circulating economy for them.
I am pretty sure their hurricane codes are out the door too.
The best teacher in the world is History.
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
Bottom line is pay me now, or pay me later. The problem is that "later" involves payment in lives too. Rather permanent debt I'd say.
Do it now, the right way. No one said that it had to be fast and all at once. Just do it the right way.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
H... for that matter, if they had been living in tents, the loss of life there would have been minimal. Tents don't crush people when they fail, but poorly constructed masonry sure does.
I realize that I am being altruistic here, but if you are going to change things for the better, you have to start somewhere.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
Since labor is relatively cheap, maybe prestressed concrete can be "introduced" to rebuild.
RE: 7.0 hits Haiti?
It looks as though the port had only on container crane and it's is leaning precariously while sitting on a collapsed dock. The trouble is that all sea going cargo is containerized and there are hardly any ships that have cargo booms.
I've been talking with an acquaintance who is in the
prestressed concrete business about getting in touch with the proper people about the same thing. The problem is where and who. The few attempts we have made have been to no avail, with one commenting we want money not advice.
Another idea that crossed my little mind is to construct single units using something approaching a round footprint. This would be very good for hurricanes and could possibly be reinforced for earthquakes.
I am also trying to locate my old ferrocement boat building buddy.
RE: 7.0 hits Haiti?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
RE: 7.0 hits Haiti?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
There rest of the Carribean has successfully practiced good construction for hurricanes and what seismic history there has been using the locally available materials. Even something as simple as vertical steel along and opening and a bond beam as a top course makes a big difference where the construction is controlled by tradition and performance and not by cost cutting.
Codes are not the only answer. - I was involved in the damage assessment starting a day after the Northridge quake and found many problems ranging from poor construction practices to solidly grouting walls where not needed that tended to concentrate loads and prevent distribution to the rest of the structure. The hospital and addition there was a prime example.
In Haiti and similar areas the real human disasters are in residential structures and depend on good construction practices since the buildings are not engineered unless they are commercial.
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: 7.0 hits Haiti?
ASCE urges donations, volunteers for Haiti relief
January 19, 2010
RESTON, VA. — The American Society of Civil Engineers urged its members and partners to join it in supporting the relief efforts organized the American Red Cross. ASCE also encouraged its members to consider volunteering to help at the scene, especially structural engineers or individuals who speak French or Creole. ... Read full article
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
I wish I had a solution for the situation that they are in but I don't. And we as engineers function by analyzing problems and coming up with solutions. Sorry, in this case, I'm stumped.
rmw
RE: 7.0 hits Haiti?
***This event supersedes event AT00398542.
Region: HAITI REGION
Geographic coordinates: 18.428N, 72.875W
Magnitude: 6.1 M
Depth: 9 km
Universal Time (UTC): 20 Jan 2010 11:03:44
Time near the Epicenter: 20 Jan 2010 06:03:44
Local standard time in your area: 20 Jan 2010 11:03:44
Location with respect to nearby cities:
41 km (26 miles) WNW (301 degrees) of Jacmel, Sud-Est, Haiti
49 km (31 miles) WSW (257 degrees) of Carrefour, Ouest, Haiti
59 km (36 miles) WSW (257 degrees) of PORT-AU-PRINCE, Haiti
ADDITIONAL EARTHQUAKE PARAMETERS
________________________________
event ID : US 2010rsbb
This event has been reviewed by a seismologist at NEIC
For subsequent updates, maps, and technical information, see:
http://ea
or
http://earthquake.usgs.gov/
RE: 7.0 hits Haiti?
"Good to know you got shoes to wear when you find the floor." - Robert Hunter
RE: 7.0 hits Haiti?
Now I live in the US and like Concretemasonry points out, we have our own construction technique problems. I saw many of those issues in the Northridge earthquake as well. Like many of you, I see pictures and video of what remains in Haiti and there is lack of proper reinforcement. Not enough rebar in relation to what appears to be the physical size of the member, no shear reinforcement, in some cases no reinforcement at all.
I also agree with others that having stricter codes is not the issue or the problem here. The problem is having enforcement of those codes. Unfotunately I also believe the problem runs deeper than some us can grasp. Like many Latin American countries more education is needed in Haiti, not just in earthquake preparedness but also in general. By the way, no disrespect is meant, I know Latin American countries have great engineers and other great professionals but we need more. Adding to the problem is the corruption that plagues many goverments of the world.
It is frustrating to know that what can be avoided with good engineering judgement can not be accomplished because of political reasons. I really hope for the best for the people of Haiti. My condolences to anyone that is part of this forum and has lost anyone to this tragedy.
I do want to mention one more point and request your input. I believe that at some point one of the reporters mentioned that beyond the immediate epicenter, there were pocketed areas of damage with areas of minor or no damage at all. I would assume that this could be attributed to the different soil profiles in these areas and how the energy was transmitted thru those profiles. Any thoughts.
RE: 7.0 hits Haiti?
Second, it is fairly common to see areas of severe damage interspersed with areas of little damage, like you describe. Structures on rock or on thin soil above rock tend to be loaded by lower peak acceleration, generally shorter-period motion, and fewer strong cycles compared to those on alluvial or other soils, because of the dynamic response. It was seen in the Loma Prieta, where areas of fill along the waterfront experienced much worse shaking than areas on rock much closer to the epicenter. In the 1925(?) Santa Barbara EQ, downtown Santa Barbara CA, on thick alluvium, was severely damaged, whereas higher ground a short way north, on bedrock or a thin layer of soil above bedrock, experienced much less damage. Think of Jello in an iron pan. One reason the Mexico City earthquake was so destructive, even though the epicenter was very far from Mexico City, was the thick lacustrine sediments.
rmw - I too would go back to DR in a heartbeat. Great people, great coffee, great merengue music by Cuatro Cuarenta. Haven't been to Haiti.
Regards,
DRG
RE: 7.0 hits Haiti?
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
I agree with you that for some it may be a matter of no housing at all, in fact for the great majority that is the case. I lived in an Adobe house in Guatemala. But like I also mentioned, the problems run deeper than a code, even code enforcement that I mentioned, but also lack of education and so much corruption. Yes, there is no point in code or code enforcement if you can not afford it but the corruption of some governments does not allow for even there own presidential palace to be safe from such a disaster, not alone a hospital (which its just a shame). The intent of my statement was not to provide a simplied analysis of the problems but rather mention some of the problems that plague our countries of the world and that I have noticed as someone who resides in the US but comes from another country. When it comes down to it and more than anything - I am angry for the loss of human life, its just not acceptable even when reality hits. Like RMW, I am also stumped.
RE: 7.0 hits Haiti?
Positive thoughts, huh? I wonder if they will get the message...
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: 7.0 hits Haiti?
Alan
"The engineer's first problem in any design situation is to discover what the problem really is." Unk.