Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: URM: Shear and Tied Veneer Walls

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Dennis S. Wish PE wrote:
> 
> It has been my understanding for the last ten years, that if the
> veneer is tied properly to a URM wall (i.e., 9" URM with 4"
> veneer) that the full thickness of the wall can be used in the
> pier analysis.
> Has there been any changes in the last few years that removes
> the veneer from the in-plane pier analysis. It is my opinion
> that the ties and mortar binding the veneer to the wall make it
> act with the wall in shear in an equal capacity as the header
> courses with a low collar joint would perform.
> I'd appreciate your comments ASAP since I have to respond to a
> proposal for another firm that wants to disregard the veneer and
> Gunnite the building.
> One more thing, if the veneer is tied, is the H/t ratio
> maintained by the thickness of the wall including the veneer.
> Again, this is how we had been doing it for the last ten years
> of so, but if there has been a change previously, I would like
> to know.
> 
> Thanks
> Dennis Wish PE
> 

If I were you, I would do a push-test on the veneer side and another
test on the URM side to find out the shear strength of the two different
materials. How're your out of plane stresses? Tied or untied veneer
tends to crack or spall and you will lose the stiffness or strength of
the veneer after the few initial shocks(out of plan).  

It is always a good idea to gunnite the URM wall for either out-of-plane
or in-plane stresses, since you really don't know what kind of grout was
used for the veneer.

Good luck,

Thomas Chiu, SE
Thomas Engineering