For those of you who are doing tower re-analysis, how are you dealing with hooked anchor bolts?
There have been thousands of hooked anchor bolts installed for communication towers over the last 30-40 years. ACI 318-08 Appendix D, equation D-5 limits the pullout strength of hooked anchor bolts to much less than the tensile capacity of the bolt. By this equation, most of the anchors do not meet the original design loads of the tower, let alone any improvements.
How do you explain to a tower owner that what has been holding his tower up for years needs to be upgraded?
Have there been a lot of anchor failures? I have not seen one or ever heard from anyone who has to know what the particulars were.
Thanks for your comments and suggestions.
There have been thousands of hooked anchor bolts installed for communication towers over the last 30-40 years. ACI 318-08 Appendix D, equation D-5 limits the pullout strength of hooked anchor bolts to much less than the tensile capacity of the bolt. By this equation, most of the anchors do not meet the original design loads of the tower, let alone any improvements.
How do you explain to a tower owner that what has been holding his tower up for years needs to be upgraded?
Have there been a lot of anchor failures? I have not seen one or ever heard from anyone who has to know what the particulars were.
Thanks for your comments and suggestions.