Anchor Bolts
Anchor Bolts
(OP)
I have designed a 65 ton bearing press and now must attach it to a foundation. As a mechanical my knowledge of concrete is limited. I have searched some literature an have some formulas, but I do not know if these are the best for my situation. The load is in the horizontal direction this causes a tension force about 25ksi in one of my anchor bolts (FEA model). The formula I used for a j-bolt suggested 27.77" for a factor of safety of 3 with 3000psi concrete. I dont have this kind of depth available. Any suggestions on formulas or anchor types other than j-bolts? I would like to keep the foundation to 24" is this reasonable?






RE: Anchor Bolts
Per an article "Design of Headed Anchor Bolts" in the Engineering Journal of AISC, 2nd quarter 1983, the embedded portion shall be:
Fu (ksi) min. embedment
58 12d
90 - 120 17d
150 19d
This values may have to be increased depending upon the edge distance and the spacing of the anchors. These values are based upon ACI 349.
Both references are useful.
RE: Anchor Bolts
thread256-140434
In the future try to restrict posting to one forum unless you have received no replies after a reasonable amount of time.
RE: Anchor Bolts
Be sure and watch your spacing and edge distance's.
Randy
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
One suggestion: have you considered isolation type anchors?
jjf
RE: Anchor Bolts
/ / / /
/ / / /
/ /PPP PPP/ /
/ / / /
/ / / /
-----------------------------
/ /
/ /
-----------------------------
X X X X X X
X X
X X
This is a crude drawing of the press. The "P" is where the pressing happens in the horizontal about 31" above the
box beam, which is 196" long. This causes the beam to deflect up. The anchors "x" are shown,the 3X locations are the anchors with the high tensile stress. The reason for the limitation on the thickness is due to existing electrical and gas lines. The electrical lines can be moved, however the gas pipeline is not ours it just runs under our facility. I could put a beam across the top but this interfers with overhead crane operations. Thanks for the information,I will check with local anchor dealers.
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
With limited thickness the most prevelent issues will probably be having a foundation system with enuf mass to prevent long term problems from vibration (press is not a compressor or similar object but the problem still exist). The type of bearing strata has big influence on this also. A majority of the time, if I can make a smaller (thinner) foundation than I like work, a solution can be found for your anchorage problem and still be economical. I've anchored big equipment with creative systems before (did similar thing with a bar-b-que grill mfgs. press). Don't sweat the bolt, make sure the system as a whole stays put first when that 65 ton press goes "BANG".
RE: Anchor Bolts
Richard A. Cornelius, P.E.
WWW.amlinereast.com