anchor bolts...do I need them.
anchor bolts...do I need them.
(OP)
Hey;
Is it stated any where in a code that a structure must be anchored down, specifically, anchored with anchor bolts to a foundation? I have a small shack (40ft long x 12ft wide x 12ft high, approximatly 41,000 lbs heavy.). Do I need to anchor it to the foundation per any codes in Canada even if wind loads cannot move it. There will be no issue for uplift since wind can not get underneath the shack.
Thanks,
M.
Is it stated any where in a code that a structure must be anchored down, specifically, anchored with anchor bolts to a foundation? I have a small shack (40ft long x 12ft wide x 12ft high, approximatly 41,000 lbs heavy.). Do I need to anchor it to the foundation per any codes in Canada even if wind loads cannot move it. There will be no issue for uplift since wind can not get underneath the shack.
Thanks,
M.






RE: anchor bolts...do I need them.
How do they erect the columns with no anchor bolts?
RE: anchor bolts...do I need them.
Never, but never question engineer's judgement
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
Why would you want to be the guy who goes out on the limb? A few well place anchor bolts would be of neglible cost, and would provide a lot of piece of mind.
Also, keep in mind, if there is a problem, it might be hard to prove that you followed a 'standard of care' consistant with what other engineers would do, as I believe most engineers would put in some anchor bolts.
JMHO.
RE: anchor bolts...do I need them.
Mike
RE: anchor bolts...do I need them.
Why take the risk?
RE: anchor bolts...do I need them.
Note that I am not "the others". If your structure is as heavy as you say it is, it doesn't need to be anchored.
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
To whom is your question directed?
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
Don Phillips
http://worthingtonengineering.com
RE: anchor bolts...do I need them.
Since the OP doesn't state what type of building this is, and what kind of foundation it is on, for the sake of discussion, I am going to suppose it is a steel framed ( or at least steel base plates) building on some type of concrete foundation.
I'm not at the office at the moment so I can't look up the coefficient of friction of steel on concrete, but supposing it is around 0.3, then the toal resistance to slideing is 41,000 lbs * 0.3 = 12,300#. 12,300#/ (41'long x 12' tall) = 25 psf wind needed to move the shack.
Not probable as I guess you could say this is part of the 'Main Force Resisting System' but its not a entirely out of the realm of possibility either in a severe wind event. Either way, its cutting it pretty close.
Of course, until I get back to the office, I'm guessing at the coefficient of friction. Or my assumptions about the type of framing could be off too.
JMHO.
RE: anchor bolts...do I need them.
Actually the friction will be reduced by the suction on the roof so the resistance to sliding is actually even less.
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
hmmm...let's throw out any engineering design and code arguments and just consider the cost versus any small advantage that could possibly be gained by putting them in. it's a no brainer (at least to me).
although, i don't really care if you put them in or not...i can't see it from here in the south anyway. but if by some chance you get a wild wind that is strong enough to move it, how many times will you kick yourself for now sticking a few bolts in there. if you don't want to put them in during pouring, spend twice as much and drill them in after the fact. either way, i'd suggest doing "something".
RE: anchor bolts...do I need them.
At the minimum of 6' on center in the US, I count even fewer bolts - 18. Probably 1/2" diameter.
Has to be less than $50.00 US. Oh, pardon me, that was yesterday... $100.00 today.
Just put 'em in.
Mike McCann
MMC Engineering
RE: anchor bolts...do I need them.
Assuming a steel structure, $50 bucks for anchorage bolts seems to me to be neglecting fab costs on the steel columns and installation, but I could be wrong (base plates, welding, drilled holes etc seem to me to be well over $50). To give the OP the benifit of the doubt, there is also the possibility of an existing or already built slab without the bolts in it. Costs can certainly go up depending on the situation.
Normally though the only cases where I would not add anchor bolts are with embedded columns.
RE: anchor bolts...do I need them.
But to be sure by comparing the cost/risk to you personnaly, just put em in.
RE: anchor bolts...do I need them.
Ciao.
RE: anchor bolts...do I need them.
RE: anchor bolts...do I need them.
Thieves are getting more sophisticated now.
RE: anchor bolts...do I need them.
Bolt the supid thing down. IRC says every 6'-0'' minimum.
Check your local codes.
RE: anchor bolts...do I need them.
The client asked the question if the shack is required to be anchored down even if the wind loading would not compromise the factor of safety for sliding or overturning. Obviously putting in anchor bolts would be the wisest thing without taking any risks. I remembered seeing or hearing somewhere where it stats a requirement for a minimum number of anchor bolts per connection. Therefore, I thought that this would be a good forum to ask the question.
I did however; just found that the Occupational Safety and Health Administration (OSHA) Safety Standards for Steel Erection require a minimum of four anchor rods in
column-base-plate connections. The requirements exclude post-type columns that weigh less than 300 lb. Columns, base plates, and their foundations must have sufficient moment strength to resist a minimum eccentric gravity load of 300 lb located 18 in. from the extreme outer face of the column in each direction.
Thanks for the discussion.
M.