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Footing Keyway

Discussion in 'Residential Foundation Codes' started by Keystone, May 31, 2019.

  1. Keystone

    Keystone Sawhorse

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    Does ACI specify having a keyway or vertical upright dowels for connection between footing and foundation or any wall above a footing when we have equal balanced backfill?
     
  2. Mark K

    Mark K Platinum Member

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    You need to talk to an engineer. As opposed to the IRC ACI does not provide prescriptive solutions for common situations. ACI 318 provides the engineer wit calculating the capacity of concrete elements.
     
  3. Keystone

    Keystone Sawhorse

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    Since not one other person replied that means one of two things;
    1. Everyone requires engineering for footing/foundation connections.
    OR
    2. I’m asking a question that really isn’t relevant in most eyes and it’s accepted practice to sign off on whatever is onsite.
     
  4. mtlogcabin

    mtlogcabin Sawhorse

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    I don't use ACI for residential and the IRC requires vertical bars in my seismic zone regardless if the back-fill is equal or not.
    2012 IRC
    R403.1.3 Seismic reinforcing.
    Concrete footings located in Seismic Design Categories D0, D1 and D2, as established in Table R301.2(1), shall have minimum reinforcement. Bottom reinforcement shall be located a minimum of 3 inches (76 mm) clear from the bottom of the footing.
    In Seismic Design Categories D0, D1 and D2 where a construction joint is created between a concrete footing and a stem wall, a minimum of one No. 4 bar shall be installed at not more than 4 feet (1219 mm) on center. The vertical bar shall extend to 3 inches (76 mm) clear of the bottom of the footing, have a standard hook and extend a minimum of 14 inches (357 mm) into the stem wall.
    In Seismic Design Categories D0, D1 and D2 where a grouted masonry stem wall is supported on a concrete footing and stem wall, a minimum of one No. 4 bar shall be installed at not more than 4 feet (1219 mm) on center. The vertical bar shall extend to 3 inches (76 mm) clear of the bottom of the footing and have a standard hook.
    In Seismic Design Categories D0, D1 and D2 masonry stem walls without solid grout and vertical reinforcing are not permitted.
     

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