Bolt Turn of the Nut Method - Bolt Force
Bolt Turn of the Nut Method - Bolt Force
(OP)
I'm trying to determine the number of turns required to get a predetermined prestress value for an anchor rod. Would I determine this per the following?:
Stress in Bolt: P/A
Strain: Stress/E (in/in)
Corresponding Anchor Change in Length: Stretch Length*Strain
I know the number of threads per inch so I know the amount of length the nut will move with each rotation and I can calculate the amount of pretension needed. Am I off base here? I can't seem to find anything in my references or online. Thanks.
Stress in Bolt: P/A
Strain: Stress/E (in/in)
Corresponding Anchor Change in Length: Stretch Length*Strain
I know the number of threads per inch so I know the amount of length the nut will move with each rotation and I can calculate the amount of pretension needed. Am I off base here? I can't seem to find anything in my references or online. Thanks.






RE: Bolt Turn of the Nut Method - Bolt Force
RE: Bolt Turn of the Nut Method - Bolt Force
Your thinking is correct however the real difficult bit is knowing the actual length of the anchor bolt to consider in the stretch calculation, example if I were doing this for a stud in a tapped hole, I would consider half of the thread engagement to be part of the effective length of the stud in the stretch calculation.
https://books.google.co.uk/books?id=NaZwZK2xm-QC&a...
“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein
RE: Bolt Turn of the Nut Method - Bolt Force