Water Heater

Large Earthquakes & Tall Buildings

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English: Mexico City Earthquake, September 19,...

English: Mexico City Earthquake, September 19, 1985. Eight-story frame structure with brick infill walls broken in two. The foundation also came off. Credit: U.S. Geological Survey Department of the Interior/USGS/I.D. Celebi Source:http://libraryphoto.cr.usgs.gov/cgi-bin/show_picture.cgi?ID=ID.%20Celebi,%20M.%2024ct (Photo credit: Wikipedia)

I always wonder how large buildings will sustain a large earthquake since both my husband and I work in high rise buildings.

I recently found an article that reviews possible scenarios with earthquakes and how various buildings will handle the stress from the shaking ground. What I discovered was interesting and a bit scary…

First, when it comes a 9.0+ earthquake many scientists really don’t know how “skyscrapers” will handle the prolonged seismic activity. For one thing, severe earthquakes are rare (thankfully) and the large earthquakes aren’t always striking urban landscapes.

Bottom line, we don’t really know.

There are some simulations that help illustrate what could possibly happen and the results were interesting. There is a theory that with a large 9.0 earthquake that tall buildings could possibly collapse since they are not designed to severely sway for up to 5 minutes. A wood-framed small home (per this research) could sustain the 9.0+ earthquake and possibly get out with broken windows and of course, damaged contents.  A brick building might partially collapse under the stress.

Here is the interesting part… say if you have a 7.0 earthquake (think Haiti) – which are often times shallow with a short and abrupt land movement for up to 60 seconds… these earthquakes could slide a wood-framed home off of its foundation, the brick building could totally collapse and the “skyscraper” might have minor damage.

The article also alluded to findings after the 1985 Mexico City earthquake and in that quake (around an 8.1 on the Richter scale) the small and tall buildings survived. Buildings with 6-15 floors had a difficult time absorbing the shock waves  therefore 60% of the buildings in this size range were significantly damaged or collapsed.

How a  building performs is the condition of the shaking and the engineering/design of the structure.

Whatever building type that you and your family live, work, or reside in… may it always be safe.

Source:

http://www.iris.edu/hq/files/programs/education_and_outreach/retm/tm_100112_haiti/BuildingsInEQs.pdf

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Water Heaters: When the Earth Shakes it’s a 600 lb Missile Sitting in Your Garage

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Water heater sm

Water heater sm (Photo credit: Wikipedia)

This may sound dramatic which I am at times (just ask my husband about my infamous hyperbole over the years) but we are all sitting on a potential 600 pound “Missile” in our homes. A full size water heater can be extremely dangerous if it’s not anchored when a megathrust earthquake hits.

In fact, according to the State of Oregon Building Codes Division: “The water heater seismic strapping requirements and applicableseismic zones have changed with the adoption of the new codes. Now all water heaters under the 2005 Oregon Plumbing Specialty Code statewide must be strapped. Water heaters installed in buildings within the scope of the 2005 Oregon Residential Specialty Code are required to be strapped in all counties in the state except the following: Wasco, Jefferson, Deschutes, Crook, Sherman, Wheeler, Gilliam, Marrow, Grant, Harney, Umatilla, Union, Baker, Malheur and Wallowa.”

Sample Product (this is not an endorsement, I just pulled the top ranking site that popped up on Google):

http://reviews.homedepot.com/1999/100067210/10-3-in-w-x-13-2-in-d-x-2-in-h-galvanized-steel-water-heater-earthquake-restraining-straps-reviews/reviews.htm

I urge everyone to anchor their water heaters before the big one hits, however, I have to add this story that I happen to find very interesting, ironic, sad, whatever… you decide.  We had our water heater replaced and I was informed by the plumber that I need to anchor it down. Not a problem. I went to… now I dislike using store names but I am going to do it this once since I know this large company (like the company I work for) has a listening tool and Google Alerts set to notify their Marketing team back at their headquarters when their brand is referenced online and I want them to see their “logic” at work. OK, so I went to Lowes in Tigard and I asked for an earthquake restraining strap. The clerk on the West side of Portland told me that they don’t have any in this particular store. I was puzzled. She then proceeded to tell me that earthquake straps are available on the East side of the Willamettte River. Huh? I countered that the subduction zone is off the Oregon coast and last time I checked the Pacific is to the west of the Willamette. In fact, the west side of Portland is probably a bit more vulnerable due to the additional proximity to the fault. The clerk nodded and agreed but then she said “try explaining this to our distribution center in North Carolina. In their mind the only thing threatening our area in Mt. Saint Helens.” Really?!? That’s just so…. 1980. So Lowes Companies, Inc. (I am really trying to hit their alerts now) will you please advise your distribution center that seismic straps need to be distributed to ALL of your Portland stores?!?

And, since Home Depot being another large corporation has alerts set up for their competitors (I know this because our company does this) as well, Hi Home Depot, can you please check to ensure that all of your Oregon & Washington stores carry this strap vs. only having it in one store for a silly reason like Lowes… Thanks.

Reference Link:

Click to access Int100.pdf