dowel length for additional new concrete at bot of exist

[delagina]

can someone refer me to how long the dowel should be. should i develop dowel to yield strength both on existing and new?

 

[msquared48]

Don't know what you are doing here, but if this is a concrete beam, I would be worried about providing stirrups here, not dowels.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[TXStructural]

Depends on the forces involved. It looks like you are using these as shear connections between an existing beam and new material being added to increase capacity. Design the dowel embed into existing using ACI Appendix D or embed a full development length. Appendix D does not now apply to chemical/adhesive anchors, but that will be in the 2011 edition and will probably look a lot like the existing appendix. Use your engineering judgment. Extend the dowels into the new material one full development length, hook as needed unless there is calculation which shows you need less. The embedded portion of dowels can ultimately be in tension as they bend along the interface.

 

[delagina]

this is related to my previous thread where i checked another engineers work but he only used bonding agent.

it was suggested by others here to add dowels for the longitudinal shear instead of just relying on bonding agent.

thanks,

 

[delagina]

nevermind this post.

i was able to get enough reference regarding strengthening of RC.


this thread is close as far as i am concerned.

thanks,

 

[BAretired]

Aw gee, and just as I about to divulge the universal law of bonding to existing concrete. Oh well, it'll keep.

BA