Potential Earthquake Damage and Important Decisions.

jill's picture

I plugged in my old address in Altadena, California to this site’s damage estimator, and placed a magnitude 7.5 earthquake (a plausible event) on the San Andreas fault. I placed the epicenter near Palmdale, California. The result I got was unsettling, and frankly made me glad I now live in an area where I only have to worry about ice storms, blizzards, tornadoes and mosquitoes. Here’s what I got:

Your test earthquake produced a simulated peak ground acceleration (PGA) of 19.033%g at your home location. Given your description, the damage factor (DF) for this event is 0.2372. This means on average you would experience $241,000 in damage (assuming a home value of $1,012,500).

If I still lived at this home in southern California, I would certainly be using this tool as a guide to help me figure out whether to buy earthquake insurance, make sure it’s bolted to the foundation, and secure nonstructural components (elements that are not part of the load-bearing system of a building). Or, I might gamble against having to spend a large chunk of my retirement nest egg for repairs to my home if I decided not to buy earthquake insurance. 

So – is 19% g at that location something I should be concerned about? It doesn’t sound that bad. To try to quantify the meaning, I did a quick review of g-forces.

When there is an earthquake, the force caused by the shaking, or acceleration, can be measured as a percentage of gravity, or percent g. The term g-force really refers to acceleration, which corresponds to the force applied to something that causes a change in position or speed. When you’re in a moving car, for example, the g-force is what pushes you around in your seat. Racecar drivers use 3-point harnesses since they can experience continuous forces up to 5 g’s during a race. The space shuttle experiences about 3 g’s on launch and re-entry.  A fighter jet pilot can experience up to 12 g’s during a maximum turn, and has to wear a special pressurized flight suit to avoid blacking out. Fifty g’s is the limit for most humans, who would die or suffer major injuries under such a load.

Earthquake forces vary greatly, and can change rapidly – back and forth, side to side, up and down. The largest earthquake forces measured have been about 1 to 2 g, but most earthquakes have lower forces. Still, even a seemingly small percent g can cause great damage to structures. Because all permanent structures are anchored in some way to the ground, and are designed not to move, it doesn’t take much ground acceleration to cause damage.

Back to my (former) house. From what I learned from my refresher, a percent g-force of 19 probably wouldn’t do much at all to me personally if I were standing outside the house in an open space. But if I were inside the house during the earthquake, I would likely sustain injuries due to breaking windows, flying glass, falling books and wall shelving, or TVs and other appliances rocketing off counter spaces – all of it “nonstructural damage.” In fact, just about any feature of a home that is not load-bearing or actual structural material is considered nonstructural. About 70% of the original cost of most buildings is in the nonstructural components, and most of the value exposed to risk from earthquake damage is nonstructural.

A logical conclusion is that both structural and nonstructural mitigation, coupled with an earthquake insurance policy – at least in the case of this level of risk – are important considerations.

Resources 

Comments

HarryWilliams's picture

The earthquakes and cyclones or ice storms are natural calamities which we cannot assume or estimate how they will be and when they will come into our lives. You have made very good point but if you can check in write my essay blog for the reports of earthquakes caused in last 150 years says you the statistics of the earthquakes.

screen23's picture

We have been so fortunate that we can play free roblox online at this website and there is no need to worry for the roblox robux generator online as we all want something like this to have the hack for the roblox game.

BachJohann's picture

Thanks for posting this info. I just want to let you know that I just check out your site and I find it very interesting and informative. I can't wait to read lots of your posts. voyance amour

jordanss123's picture

thank you very much for sharing the best post with all needed stuff. www.yeezy350find.com

HarryWilliams's picture

That is very good thinking by you to keep damage estimator in your old house and try it to measure the magnitude of the earthquake through it. I also read an article which was written by you from best-essay-writing.services blog while I in search of my college assignment work of my subject articles from that blog.

BachJohann's picture

very interesting post.this is my first time visit here.i found so mmany interesting stuff in your blog especially its discussion..thanks for the post! cartoon HD

lionel's picture

Construction companies and building owners must think about these things mentioned here. These are some effective techniques to deal with the issue of earthquakes and the damages caused by the same. Structural and nonstructural mitigation, coupled with an earthquake insurance policy will be the best way of dealing with it.  American Improvers Home Extension

HannaChriz's picture

This is the first time I have come across this site and came to know about this community that provides services for Earthquake Forecasting and Hazard analysis. The group of members of this community gives their best for developing tools that will forecast events like earthquake, floods and other hurricanes. Read Full Article

Enimeny22's picture

Me too. I happy be here. I make homework help essay writing (doahomework.com)  and can take a lot interesting things from this site. Thanks.



newtoner's picture

 

I never pass by a worthy piece of information. Your post is exactly like that. Thanks! By the way, I can recommend one very good essay help website. I think your guests will appreciate it.


Roman's picture

Thank you for this post. It is hard to find really important info while surfing the Net. Guess what? I also have a piece of news for you! I have found a trustworthy custom writing service and share it with you https://rocketpaper.net/harvard-mba-essay-writing

BachJohann's picture

That is the excellent mindset, nonetheless is just not help to make every sence whatsoever preaching about that mather. Virtually any method many thanks in addition to i had endeavor to promote your own article in to delicius nevertheless it is apparently a dilemma using your information sites can you please recheck the idea. thanks once more. http://www.mansfieldsailingclub.com/

BachJohann's picture

Please share more like that. آموزش سالیدورک

BachJohann's picture

This one is good. Keep up the good work I also visit here:Microdermabrasion and I get lot of information.

Risk Alert