Bolt bearing strength in concrete or masonry 1

[ARKeng]

This has been a repeated question over and over on this forum. I've never seen an answer I felt "solid" about using though I've gotten some good advice on how to approach it. Today, I believe I have stumbled upon a "source" that can be used for these types of "through bolt" type problems in the least likely of places: The American Wood Council has a Technical Report 12 "General Dowel Equations for Calculating Lateral Connection Values with Appendix A" (link below to the copy I found.

AWC Technical Report 12

This source essentially contains the backup and derivation for all the dowel equations in the NDS. Appendix A gives a value to use for "Fe" for concrete in the same NDS equations used for dowel connections in wood. The main body discusses and has examples of the calculations, and even addresses how to handle hollow members like would occur in hollow CMU or HSS members.

Hope this helps everyone!

 

[klaus.]

Thank you for sharing this useful information


best regards
Klaus

 

[P1ENG]

Some thoughts:

What do you do with duration factor if calculating this using steel side and concrete main members? It says steel bearing stresses have been divided by 1.6 so that duration factors may be used. It does not say the same thing for the concrete section.

The notes in the table limit the Fe value of concrete to 7500 psi, so going to a stronger than 2500 psi concrete does you no good.

Remember the NDS uses ASD while ACI uses LRFD.



Juston Fluckey, SE, PE, AWS CWI
Engineering Consultant