Tuesday, September 07, 2010

Good post-earthquake commentary

Some good post-earthquake comments and science around the traps.

And I enjoyed this comment by Owen McShane over at Frog Blog’s earthquake thread:

_Quote The BIG story is that this massive earthquake in a major city has resulted in zero deaths. The timing had much to do with it of course because most people were safe at home in their lightweight timber framed suburban beds.
    Had they been in offices many would have been turned into hamburger my moving filing cabinets etc.
    The low damage level is a tribute to our engineers scientists and our building codes.
    Hopefully more people will be aware that “solid brick” is not your best friend in an earthquake.
    Of course we know that Christchurch is subject to earthquakes. That is why there has been a major programme for strengthening older buildings. Every part of NZ is at risk of earthquake. It’s just some are more at risk than others.
    The light timber frame is the ideal construction. I remember a seminar on earthquake design from an expert who had just returned from the great Alaskan earthquake. I house, which could have passed for any bungalow in Auckland, rolled down a steep hill during the earthquake. The window panes remained intact.
    Remember, an earthquake of this magnitude killed 230,000 people in Haiti. Mud bricks may be romantic but they kill you in an earthquake.
    Also those people who have to leave their homes do not have to worry about squatters. They have secure title to return to.
    It is also amazing how quickly services etc are being restored. There is little one can do to prevent underground effects such as broken pipes and gas lines.
    The response time is remarkably good.

If you see other good commentary around the traps, leave a links in the comments and I’ll post them here on the front page.

  • Spotted by Mark Hubbard: a very good article by Frederic Sautet at his 'Coordination Problem' blog, comparing Chch and Haiti earthquakes:  Earthquakes as Economic Phenomena.

    _QuoteThose who live in Christchurch were saved by capitalism and the accumulation of capital it has enabled over the years. Natural disasters are economic phenomena. Governments, including in the West, often ignore this truth to the detriment of the victims who suffer twice—once from the earthquake itself, and a second time from the consequences of poor government policies.

Labels: ,

6 Comments:

Anonymous Mark Hubbard said...

Owen McShane has got it right. Think of this; that was the same scale quake as they had in Haiti where it killed between 250,000 and 300,000 people.

Here, no one has died, and I know they are worse off where the soil liquified on the flat, but just two days after a major quake, I was sitting in my office, where I am now, working as normal: with water and sewage, power and Internet. As if nothing had happened.

That is a miracle, but a very man-made one, as miracles are.

(Don't want to do it again though.)

9/07/2010 09:43:00 am  
Anonymous Falafulu Fisi said...

The occurrence of earthquakes follow a power-law probability distribution (a very well established fact), which is hard to predict. Economic system/s also follow this non-symmetric probability distribution (i.e., a power-law which has been empirically confirmed), but most financial risk managements of today, still use the useless symmetric Gaussian (normal or bell-curve) probability distribution, which has lead to under-evaluations of risks in some financial instruments. What happened when risks are being under-evaluated? Financial earthquakes with huge magnitudes (such as recent financial crises) can occur (to devastating effects).

I wouldn't be surprised if Christchurch engineers/scientists (from a few decades ago) had used the fact that earthquakes follow power-law to evaluate the risks for existing buildings (at the time) if they needed reinforcement or applying new designs for future new buildings so they can withstand certain earthquakes magnitudes.

If the risk evaluation of an earthquake above a certain magnitude says that it occurs only once in every 500,000 years, then it is not worth spending huge amount of money in designing a building to withstand such earthquake because it will never happen during our lifetime.

9/07/2010 10:50:00 am  
Blogger Owen McShane said...

The Napier earthquake was a timely wake-up call and since then whenever we might be getting complacent another jolt reminds us of the need for eternal vigilance and ongoing research.
I was privileged to be in a position to assist with the development of lead rubber bearings as part of base isolation systems which have made bridges and critical buildings more quake resistant.
I was discussing the energy absorption process with a physicist and he explained that the four inch nail is a useful energy absorber and makes a contribution to the performance of timber framed buildings. He was confident that after a quake many of the nails in your typical house would to too hot to touch.
We licensed them to Californian companies and there has been a massive regtro fitting of bridges throughout the US – they learned that lesson from the last SF quake when bridges collapsed and closed down the network.
Katrina was not a quake but reminded us that elevated highways are the best route for emergency evacuation because they are not prone to flooding or rubble falls. Contrary to what some seem to believe public transport is virtually useless at times like this because it does not take people where they want to go and people cannot take any belongings or pets.
My worry about Waterview and the viaduct extensions is that both go underground and more importantly below sea level. Consequently they are likely to be full of water in a Tsunami disaster and we know that people’s fear of tunnels increases dramatically when earthquakes are running around the neighbourhood.
Then people run out of gas in panic and they take ages to clear.
So head for the viaducts and high highways and think of the scientists whose base isolation systems have made them safe.

9/07/2010 11:41:00 am  
Anonymous Mark Hubbard said...

Very good article comparing Chch and Haiti earthquakes at the 'Coordination Problem' blog:

http://www.coordinationproblem.org/2010/09/earthquakes-as-economic-phenomena.html

Quote: Those who live in Christchurch were saved by capitalism and the accumulation of capital it has enabled over the years. Natural disasters are economic phenomena. Governments, including in the West, often ignore this truth to the detriment of the victims who suffer twice—once from the earthquake itself, and a second time from the consequences of poor government policies.

9/07/2010 11:46:00 am  
Anonymous James said...

Someone needs to tell those fuckwits at the Standard (yes I know...why bother)but the first post was how regulation was what saved so many lives and that a free market approach would have resulted in chaos.

But did regulation create these advanced preventative measures spoken of here...or the power of the market and the creativity it encourages and rewards?

9/07/2010 01:38:00 pm  
Anonymous Anonymous said...

Most of the insurance companies have underwriters and so have limited themselves to probably 25% of the actual cost of the repairs. Thus the vast majoriyt of the risk will be met by overseas underwriters. In the long term NZers will pay for this through higher premiums, and thus the 'names' will hopefully not go broke in the process.However, for NZ it looks like our Broken Windows opportunity will be about 500m, or is that not the case?
But I suppose the real broken windows falacy will be shown the uninsured. The assumed the risk instead of paying someone else to take it off their hands, and now have nothing. When they repair their properties, the opportunity cost from the expediture will be forever lost from their lives.

9/08/2010 05:56:00 am  

Post a Comment

Respond with a polite and intelligent comment. (Both will be applauded.)

Say what you mean, and mean what you say. (Do others the courtesy of being honest.)

Please put a name to your comments. (If you're prepared to give voice, then back it up with a name.)

And don't troll. Please. (Contemplate doing something more productive with your time, and ours.)

<< Home