What is the proper anchoring design againest a uplift force
What is the proper anchoring design againest a uplift force
(OP)
I am designing a roof top supporting structure for a four legged telecom tower to resist a uplift force of 770kN per one leg.Beams of the above structure has been designed assuming simply supported and no moments will be transfered to existing columns. More over chemical anchors will be used to resist the uplift force.What is the most suitable approch for a chemical anchor designing for supporting columns of size 250mmX250mm? Will this existing column is strong enough to carry such a loading.






RE: What is the proper anchoring design againest a uplift force
RE: What is the proper anchoring design againest a uplift force
RE: What is the proper anchoring design againest a uplift force
RE: What is the proper anchoring design againest a uplift force
Sorry, but it sounds like you need more supervision. Hire a structural engineer. Not trying to be ugly, just truthful.
RE: What is the proper anchoring design againest a uplift force
RE: What is the proper anchoring design againest a uplift force
This is not just an issue of bolting down the legs. The building structure needs to be verified as well, and this sounds a bit scary. I hate telecom towers.
RE: What is the proper anchoring design againest a uplift force
Thus in summing up I agree with everyone general comments about getting a structural engineer on board that has some experience with this kind of application.
When in doubt, just take the next small step.
RE: What is the proper anchoring design againest a uplift force
Build all the way back to the structural steel inside all four of the columns, use multiple-through bolts to the reinforcing and internal column steel members with shear bolts, develop a complete steel pad fastened to the vertical steel inside the column on the roof (penetrating the nominal roof deck of course) then fasten the tower to the exposed steel.
The theorectical wind could come from any direction, will come from any direction actually, so all four attachment points have to be equally strong against the full up and down worst case forces. As mentioned, pre-tensioning is essential against the vibrating wind loads.