Shear Transfer across Vertical Construction Joint
Shear Transfer across Vertical Construction Joint
(OP)
Hi
When transferring a large shear force across a vertical construction joint, is the ACI shear friction method an appropriate shear model for design.
I have compared different scenarios using the shear model for beams and have found that a typical situation (0.25% flexural reo and Asv/s=4.52) I can get a shear capacity of 1.7N/mm^2 (roughly 0.04*f’c).
When using the shear friction model, if I load the cross-section full of reo so that I have 1% reinforcement crossing the shear plane I can get a shear capacity of 3.0N/mm^2. It does not seem intuitive to me that I can get more shear capacity thru dowel action than by a monolithic section.
Also, is the shear friction method only applicable if the dowels are located in the compression zone of a suspended slab?
This has all come about from a terrible detail where I am attempting to transfer a large shear force across a vertical construction joint in a suspended slab (at least for now, I have a feeling that I will be relocating the construction joint).
All input will be appreciated.
Thanks
When transferring a large shear force across a vertical construction joint, is the ACI shear friction method an appropriate shear model for design.
I have compared different scenarios using the shear model for beams and have found that a typical situation (0.25% flexural reo and Asv/s=4.52) I can get a shear capacity of 1.7N/mm^2 (roughly 0.04*f’c).
When using the shear friction model, if I load the cross-section full of reo so that I have 1% reinforcement crossing the shear plane I can get a shear capacity of 3.0N/mm^2. It does not seem intuitive to me that I can get more shear capacity thru dowel action than by a monolithic section.
Also, is the shear friction method only applicable if the dowels are located in the compression zone of a suspended slab?
This has all come about from a terrible detail where I am attempting to transfer a large shear force across a vertical construction joint in a suspended slab (at least for now, I have a feeling that I will be relocating the construction joint).
All input will be appreciated.
Thanks






RE: Shear Transfer across Vertical Construction Joint
RE: Shear Transfer across Vertical Construction Joint
http://www.nceng.com.au/
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RE: Shear Transfer across Vertical Construction Joint
Do you guys spend your saturday's keeping up with eng-tips?
It's large, V*/(b*D) is 2.3N/mm^2 if it where a monolithic section. I'm not going to run the gautlet and just re-locate the joint. They won't like it but I don't care.
Thanks for the help.
RE: Shear Transfer across Vertical Construction Joint
RE: Shear Transfer across Vertical Construction Joint
RE: Shear Transfer across Vertical Construction Joint
Dik