Fake 7.5 quakes anger Chch residents
Tue, 17 Apr 2012 6:09p.m.
By Annabelle Tukia
Simulated earthquake testing in Christchurch is angering some residents whose homes are being shaken.
Building foundations on liquefaction prone land have been put through a simulated 7.5 magnitude quake at Christchurch’s QEII stadium.
One of the tests lasted ten seconds and was not unlike what the city has been experiencing for the last 18 months.
Nearly 300kg of explosives were used to simulate earthquake forces for the purpose of testing building foundations.
Tonkin and Taylor geotechnical engineer Peter Millar has been involved in the tests.
“In the test panels there the magnitude would have been close to 7.5. This is what we've designed this to, but what happens is the energy dissipates with distance away and so by the time it’s got to the nearest residence it's at a very low level.”
But after enduring months of earthquakes and aftershocks some residents say this second round of testing at the stadium is the last straw.
Keith Mackay is not happy.
“It was much greater than I expected, in short it was frightening.
“Actually this house raised. I was on the telephone looking out the window at the time of the explosion and visibly noticed the house lifted.”
In a round of testing last November four different foundation systems were tested and Mr Millar says that revealed one in particular that coped well with liquefaction processes.
Today's testing was about refining those results.
“By stabilising a layer about 2m deep with cement, and what that does is it confines the material underneath and reduces the levels of settlement.”
Although the testing is in its early stages, it is already generating interest with nearly 10,000 homes in Christchurch sitting on liquefaction prone land.
EQC Canterbury events manager Reid Stiven says it is necessary.
“EQC are trying to establish whether we’re able to effect repairs to land in tc3 categories [blue zones] that are cost-effective and durable and may allow us not to have to go down the track of a site specific foundation development.”
Tonkin and Taylor say today's testing is likely to be their last at the site, which should be good news for the QEII residents who say they have had enough.
Post a Comment
Before commenting, please take the time to read our moderation guide
(Won't be published)
18/04/2012 8:09:47 p.m.
It really would have been appreciated that surrounding suburbs be given a 'heads up' about this. With social media around it's very easy to share information - if this news article had been on last night to inform us of the testing then tonight's article of complaint wouldn't have occurred. And it's not just the people in the surrounding suburbs that are affected, it's the animals. If I'd known about the testing I would have arranged for my dog to be elsewhere yesterday. Instead, we came home to a clearly petrified puppy. Today she is still tortured by yesterday's blasts and jumps and barks at every little noise and bump.
18/04/2012 11:54:28 a.m.
LOL what a bunch of idiots! it may only go 2 block wide, think of the damage 2 blocks below! this should of been tested somewhere were earthquakes are not a problem! stupid stupid stupid!
18/04/2012 11:47:16 a.m.
I can understand the logic of testing on the land currently affected by liquifaction. After all this is something that could not reasonably be done elsewhere is via a computer simulation. I think what Christchurch residents should be worried about is the fact that engineers and eathquake experts had no idea that there was a fault line running through Christchurch. What else don't they know?
18/04/2012 1:15:09 a.m.
Has someone lost their minds. This is crazy.
17/04/2012 11:23:13 p.m.
I wasn't happy about this either. I heard no warning siren and it sounded like someone was playing the drums on my wall and it shook my house quite strongly. I live two streets over from qe2 and I was terrified
17/04/2012 8:35:45 p.m.
No warning this was happening today. We are 2-3km from QEII and it was scary and loud. Our house jumped, was shaken then rolled for around 30 seconds. Their suggestion that only a few homes would have felt it was total lies.
17/04/2012 7:38:21 p.m.
It would of been nice if they had of warned us they were doing it.
32 months after the first earthquake, dozens of Christchurch...
All 350 passengers on board a commuter train that derailed e...
Video has emerged of a skydiving incident in Motueka last ye...
The woman who first tried to lift the lid on paedophile Jame...
Copyright © 2013 MediaWorks TV. All Rights Reserved.