VOLCANO MADNESS: Re: [Geology2] Fwd: Construction errors responsibe for the collapse of the Christchurch CTV building (killing 115 people)

Hi Vic,

I am very familiar with the structures in Memphis, TN and St. Louis, MO. Both cities have their oldest buildings nearest the river, including a dilapidated bridge in the latter city. How would I rate their preparation for the big one in these two cities: 0. A big fat zero.

The structures-concrete multi-layered parking and masonry and brick buildings. The newer bridges have been retro-fitted for a moderate quake, but if an 8 pointer should occur, don't bet on any Memphians making a break for Arkansas or Missourians reaching Illinois.

Outlying areas near Memphis use chains on the overpasses up to 2 counties away, so keeping I40 open should be feasible, but the city itself is a Christchurch in the making. The death rate would be enormous for both cities and panic would clog the major routes out of each city. In Memphis, there is a good chance that if folks stayed off I40, they would make it out fairly well. There are many routes in order to disperse in all directions, except west (given the bridge should be compromised). St. Louis has the same set up. Stay off major interstates. Take the back roads. Get out of the city asap.

Worse case scenario for St. Louis is a Busch stadium would be full. It and the nearby parking garages would be toast. The river is so close, it's almost part of the structures, and the downtown area is immediately to the east. This placement would guarantee folks would have a time getting out, especially if the bridges were compromised.

I was in downtown Memphis in December and as I stood on Beale St., I took a good look around. Memphis is in such a perilous condition. Miocene sand goes straight down to the bedrock, but in order to reach the latter, you'll have to go about a few hundred miles. Liquefaction would be so bad that one could not even stand up, much less get the heck out of Dodge. Brick and masonry everywhere. Old historic buildings crowd downtown, as well as the new FedEx Forum, the Pyramid, and the Peabody. What's worse is the water table is very high.

My plans are to move, within the next few years, to Dyersburg, which is a mostly rural area near the Mississippi River. I will have access to many of the features created by the 1811-12 quakes, as the MS River bridge will be about 20 miles away. Yep. I want to move nearer the NMFZ. Crazy, but I want to investigate this area further, including the area where I spent the first 6 years of my life--the bootheel of Missouri. Also, I will be much nearer to Reelfoot Lake in TN and southern Illinois, where there are many geological features to explore.

Back to your question at hand, I have no doubt that if a large quake occurred that the two aforementioned cities would experience the worst in human nature, which is directly opposite of what occurred in Christchurch. Memphis and St. Louis have a rabid crime rate that would come to full term during a crisis. Where's Kurt Russell when you need him, eh?

Lin

On Thu, Feb 23, 2012 at 12:42 AM, Victor Healey <vic.nospam@gmail.com> wrote:

I wonder how many structures in the USA will fail catastrophically in the next big quake do to errors in construction that do not meet basic earthquake standards?
Sometimes this can be due to criminal elements cutting corners to save money.

Begin forwarded message:

Overview of the articles we have written on the New Zealand earthquake
A technical report on the deadly collapse of the Canterbury Television building has revealed what caused the structure to fail in last February's magnitude 6.3 earthquake in Christchurch New Zealand.

The collapse killed 115 people, including 65 foreign students.
The report found the CTV building did not comply with the building code when it was first built in 1986.
Three critical factors were found that contributed to the building's collapse:
- Intense horizontal ground shaking.
- Lack of ductility in the columns, making them brittle.
- Asymmetrical layout of the shear walls, making the building twist during the earthquake, placing extra strain on the columns.

Labour Party earthquake recovery spokeswoman Lianne Dalziel said the report's conclusions were "devastating". "The report has revealed thatthe building was not built to code – a devastating finding, considering the collapse of this building was responsible for more than 60 per cent of the deaths in the earthquake," she said.

Image courtesy halfdone.wordpress.com

Full Press report from the New Zealand Government
Image courtesy Shelby-dog
Intense ground shaking, non-ductile columns and the asymmetrical layout of shear walls were the critical factors contributing to the collapse of the CTV building during the 22 February 2011 Christchurch earthquake, a Department of Building and Housing technical investigation has found.
The Government ordered the investigation in March 2011, along with investigations into the failure of the Pyne Gould Corporation, Forsyth Barr, and Hotel Grand Chancellor buildings, following the 22 February 2011 6.3 magnitude earthquake, which claimed the lives of 184 people, including 115 in the CTV building.
The Department of Building and Housing established a group of leading engineering consultants to conduct the investigations, which were peer reviewed by an expert review panel, chaired by construction law expert Sherwyn Williams.
The comprehensive investigations included eye witness accounts, photographs, site examinations, sampling and testing of materials, structural analysis and testing of various hypotheses using established engineering models.
The investigation into the 1986 CTV building was conducted by Hyland Consultants and StructureSmith.
Three critical factors were found that contributed to the building's collapse:
    – Intense horizontal ground shaking.
    – Lack of ductility in the columns, making them brittle.
    – Asymmetrical layout of the shear walls, making the building twist during the earthquake, placing extra strain on the columns.

The ductility of the columns (and strength) and the asymmetrical layout of the shear walls were found to have not met the building standards of the day (1986).
Other factors that may have contributed to the CTV collapse included:
    – Low concrete strengths in some of the critical columns.
    – Exceptionally high vertical ground movement.
    – Possible interaction of columns and concrete spandrel panels (on the external face of the building), making the columns less flexible.
    – Separation of floor slabs from the north core of the building.
    – Structural influence of the concrete masonry walls, making lower floors more rigid than upper floors, which placed additional stress on the upper columns during the earthquake.

Although it is not possible to be definitive on the sequence of the building's collapse, the common denominator in all collapse scenarios identified by the Expert Panel was the failure of one or more columns on the east face of the building. This is consistent with eye-witness accounts of the building during the earthquake.

Current building requirements are more stringent now than in the 1980s when the CTV building was constructed. Standards have progressively improved over time as more is understood about how buildings respond in earthquakes.

Department of Building and Housing Chief Executive, Katrina Bach, said the Department has already taken action on some of the Expert Panel's recommendations, and will implement the others working with the building and construction sector and local government over the coming months and years.

Image courtesy Shelby-dog
"The findings of the investigations and the learnings from 22 February will make a difference to the way the buildings are designed and constructed in the future – both in New Zealand and internationally." Ms Bach said the technical investigation would inform the Canterbury Earthquakes Royal Commission of Inquiry.

"Copies of the Expert Panel report have been provided to the Police and the Institution of Professional Engineers New Zealand for their consideration and action as appropriate."
Ms Bach said she expected Territorial Authorities (councils) to take close notice of the reports as they developed there own programs of work to address earthquake risks.

She also encouraged property owners and building users to seek information about the standard of their buildings.
Thanks to ER reader Lee from Christchurch for attracting our attention and courtesy to use his pictures
Full report courtesy the New Zealand Department for building and housing.

Image courtesy Shelby-dog