School Used as Emergency Shelter - Any Design Changes?
School Used as Emergency Shelter - Any Design Changes?
(OP)
I recently completed the structural design of my old grade school.
The school has came back and said they want to use the new school as an emergency shelter in the event an emergency comes up.
Are there any changes structurally I would need to do to my design?
To me, it would seem it is just back-up power (redundancy), lighting, food and water storage that need to be considered and nothing structural.
Thank you,
D
The school has came back and said they want to use the new school as an emergency shelter in the event an emergency comes up.
Are there any changes structurally I would need to do to my design?
To me, it would seem it is just back-up power (redundancy), lighting, food and water storage that need to be considered and nothing structural.
Thank you,
D






RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
If you have seismic considerations, you might increase your seismic loading similarly.
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
http://www.FerrellEngineering.com
RE: School Used as Emergency Shelter - Any Design Changes?
This is a loaded question because the owner's expectations of a shelter are usually very different than what can be provided.
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
They do not address the structural systems of a gym or other vulnerable structures. The concept is life safety/survival under severe conditions. Obviously a tall floor space would be bad choice, but the lower areas with more stability and less exposure make more sense.
Most of the suggestions (not a code) are based on life safety and protection from winds and especially projectiles, because FEMA has a great background in that area. For residential protection from projectiles and debris (the largest cause of deaths), there only a very few select wall systems recommended because of the extensive testing over the last 15-20 years or so. These can be used or existing walls can be modified to approximate the results, but not quantified.
It is well worth the time to look over the concepts and see how they apply.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: School Used as Emergency Shelter - Any Design Changes?
Than again, my old grade school was built pre-air conditioning and pre-Columbine (warfare) problems, so maybe new schools have "no" outside windows .....
RE: School Used as Emergency Shelter - Any Design Changes?
Has the contract been awarded? You mentioned you had bids. Change is significant that re-tender might be in order.
I would suggest that you do not 'push for them not to go this route'... in the event that there is a problem and collapse, you may be in for serious law suits.
If the school wants this, then deal with it as a significant change.
Dik
RE: School Used as Emergency Shelter - Any Design Changes?
FEMA 361 does address the structural design of buildings used as community shelters. It deals with both loads and projectiles. ICC 500 is the newer "code" version of the FEMA guidelines.
RE: School Used as Emergency Shelter - Any Design Changes?
There is a *very valid* reason that hallways and bathrooms are the traditional areas of choice for 'hardening'. Your customer is trying to "reinvent the wheel". Sometimes [almost always] the 'usual & customary solution' represents an optimal design.
Wheels are round for a reason.
RE: School Used as Emergency Shelter - Any Design Changes?
Done all the time.
RE: School Used as Emergency Shelter - Any Design Changes?
Also - Check with the owner to determine the tornado category, typically in fujita scale, F1, F2, etc. go to national weather website to find the corresponding 3-sec guest wind speed.
RE: School Used as Emergency Shelter - Any Design Changes?
Keep in mind this is really for tornadoes and not hurricanes that typically have much lower winds. The concept is meant to be applied to small life saving structures for survival and not for groups with longer term needs.
Windows obviously have a more relaxed threshold, because shutters or other systems are also expected to be used or required.
Dick
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: School Used as Emergency Shelter - Any Design Changes?
The anti-gym bias is typical with a lot of folks because for many years schools were instructed to stay away from large gym rooms because of their tendency to collapse in high winds. People were instructed to sit in the long hallways with their head between their legs - with light gage metal deck roofs above and glass windows and doorways at either end...
I designed a school gym in the 1990's under FEMA 361 for 200 mph. The school was actually a new one my two kids were eventually to attend. After it opened I visited with the principal and asked if he was all clear on the use of the gym for storm shelters. He blinked at me and said, "No, no. The Civil Defense inspector slapped a shelter sticker on the mechanical room - that's where we should go." I had to do a lot of communicating with the school district to straighten that out as the mechanical room was only framed with light steel beams, hollow core floor above (for the air handlers) and was perhaps the worst place in the world to go. They finally instructed the principal to head to the VERY hardened gym structure...much to my relief.
Texas Tech (Mehta et al.) have provided testing for projectiles and in some cases 4 1/2" concrete walls are enough. FEMA 361 suggests 6" thick. I've worked with Texas Tech on projects in the past and we've been in situations where a 4 1/2" concrete wall panel was acceptable. The missle test is 100 mph (not 145) and a 15 lb. 2x4.
dhoward - you use the term "emergency shelter" which doesn't necessarily mean tornado or hurricane. You might clarify.
RE: School Used as Emergency Shelter - Any Design Changes?
JAE is exactly right.
RE: School Used as Emergency Shelter - Any Design Changes?
Count me as a vote for JAE regarding gym shelters. I have designed three schools in Florida with such a requirement. It's been awhile so I can't recall the State document we were required to follow for the design, but roof uplift loads in the corners of the building can be on the order of 200 psf or more. The walls are either tilt-up concrete or solid-filled & reinforced masonry.
RE: School Used as Emergency Shelter - Any Design Changes?
If you have designed such a beast - KUDOS - and I believe it could be done - just the ones I have seen would be worthless.
RE: School Used as Emergency Shelter - Any Design Changes?
Thank you for the ideas and suggestions.
RE: School Used as Emergency Shelter - Any Design Changes?
JAE got it right; it's readily 'doable' with a big budget. Heck, the Army made an above-ground bunker that withstood being inside an atomic fireball. $$$$$$
RE: School Used as Emergency Shelter - Any Design Changes?
RE: School Used as Emergency Shelter - Any Design Changes?
Dik
RE: School Used as Emergency Shelter - Any Design Changes?