Tornado rips through town - GIF

[Altair]

Tornado rips through Andover, Kansas.




Previously:

Historical map of tornadoes in the U.S. - photo
Tornado shapes and sizes - photo
Driver pulls out of garage just as tornado hits - GIF
Car sucked by tornado - GIF
Pickup truck drives away after getting tossed around by tornado - GIF

[rgsparber]

And that is why I don’t live outside of Chicago anymore! These twisters are absolutely frightening.

Rick

[mansworld]

In Tornado prone areas, why do they keep building lightweight flimsy houses? They build the dream home from wood with a tiny above-ground/ underground concrete storm shelter!

[nova_robotics]

In Tornado prone areas, why do they keep building lightweight flimsy houses? They build the dream home from wood with a tiny above-ground/ underground concrete storm shelter!

This is long and drawn out, but it's worth the read.

So this is completely counter-intuitive and I absolutely did not expect this to happen. I did a $40-ish million dollar tornado recovery job a few years ago. There were all kinds of structures on this site. Steel frame with various types of siding (mostly glass fibre reinforced plastic, some old trafford tile), wood framed structures, block structures as well as block structures with brick veneer. Some structures were on the ground with concrete foundations, some elevated structures (overhead conveyors). Where's the surprise? Steel framed structures held up the best with minor damage to siding and roofs, wood frame structures were second best with minor to moderate damage but generally still survived, and brick and block buildings were absolutely leveled, almost without exception. The ones that were somewhat left standing were damaged beyond being recoverable, with every mortar joint being completely broken. There was a big block wall, maybe 50 feet long and 12 feet high. I could get it to rock and flex by pushing it only with my hands. Even a small CMU 100-ish square foot pump house that looked like it should be able to withstand a direct strike from an Abrams tank was taken down to the foundation.

Now I have to qualify this. The brick and block structures, some of which were multi-story office buildings, were just mortar and brick/blocks. The blocks were not concrete filled and rebar reinforced. But either way these structures DO NOT stand up like you would expect. Pretty much without exception every brick and block building was completely demolished. This was absolutely and completely counter-intuitive, at least for me. I did not expect multiple wood structures with FRP siding to shrug off an F3 tornado while CMU builds were destroyed. Mind blown.

So I ran some numbers afterwards, and it does actually make sense. If a tornado can produce even a 1 PSI pressure differential, that is an absolutely enormous distributed load on that wall. A 10ft x 10ft section of block wall will experience 14 tons of force SIDEWAYS under those conditions. Wood and steel frames can tolerate those side loads, bricks and blocks cannot. Those wind loads have the tendency to cause the wall to bend or flex, which breaks all the mortar joints. Once the mortar joints are gone it's just stacked blocks held there by gravity.

Anyway, that project was a real eye opener. I'm certain if you had something like an ICF structure, or if you actually installed the CMU blocks properly with rebar and concrete fill the situation would be much different. But concrete still sucks in bending.

[Hoosiersmoker]

Fortunately enhanced EWSs make mass casualties from tornadoes all but a thing of the past.

[Philip Davies]

Fortunately enhanced EWSs make mass casualties from tornadoes all but a thing of the past.

I didn’t know what EWS meant, so googled it, and kept getting “news now” featuring yer beloved ex-president!

[Frank S]

I didn’t know what EWS meant, so googled it, and kept getting “news now” featuring yer beloved ex-president!

Googling or Binging or Yahooing, or whichever your favorite search engine will always yield a wide range of possibilities never even remotely related to the subject you are in need of inquiring about. In this case the EWS stands for Early Warning Services, it can also stand for Early Warning Systems which would be the nuts and bolts hardware used by the services. Unfortunately, the Acronymization of so many things have become one of the banes of society's confusion.

[mklotz]

I didn’t know what EWS meant, so googled it, and kept getting “news now” featuring yer beloved ex-president!

Philip, bookmark this site...

https://www.acronymfinder.com/EWS.html

It's rare that I can't find the definition of an acronym there, even SWMBO. :-)

[hotdog0627]

Whenever I encounter an acronym in an email, I'd reply back and say "... sorry, I do not understand... Too many TLA's that I dont know."

So what's a TLA? ... Three Letter Acronym

[Hoosiersmoker]

Whenever I encounter an acronym in an email, I'd reply back and say "... sorry, I do not understand... Too many TLA's that I dont know."

So what's a TLA? ... Three Letter Acronym

EWS isn't technically an acronym, it's initialism. AIDS (Affected Immunodeficiency Syndrome), YAHOO (Yet Another Hierarchical Officious Oracle), the group ABBA (Agnetha, Björn, Benny, Anni-Frid) are acronyms. They form "words" or letters that can be pronounced as words anyway. FYI...