Shearwall Reinforcement Cast in Wrong Location 1

[tclat]

Dear All,

I have a 10" r/c shear wall where the starter bars are cast in the wrong location by 4" over the entire length of the wall. The wall is in a basement and the architect will allow us to increase the wall thickness to 14" in the basement only. ACI 12.14.2.3 allows non contact lap splices up to the smaller of 6" or 1/5 the length of the lap splice for flexural members.

I was thinking of cranking the outside bar at a 1:6 slope and leaving the inside bar as is while using a non-contact lap splice. In the location of the crank, I'm thinking a capping beam would also be useful to confine the crank. Is this an appropriate detail?

Thanks

 

[KootK]

I think that your detail is right on the money. Non-contact lap splices offset perpendicular to the member have caused problems in the past. Two other options:

1) abandon the dowels and drill and epoxy new ones if you can make it work. No doubt you've already checked this.

2) extend the rebar from the wall above all the way down to the foundation so that your non-contact lap is a story long. Depending on where things are at, this might be cheaper than the beam formwork.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[KootK]

Another option is to place leg down U-bars at the top of the 14" walls and make the non-contact lap splice work as a strut and tie joint. At the concentrated zones, you'd need to get the same job done with rebar ties. This might be the most contractor friendly option after replacing the dowels.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[slickdeals]

Take a look at this report, particularly Page 20. This discusses the strut and tie model for such a load transfer.

 

[msquared48]

Link?

Mike McCann, PE, SE (WA)

 

[slickdeals]

Oops. Here you go.

http://www.wsdot.wa.gov/research/reports/fullreports/417.1.pdf