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Anchor bolt o.c. spacing— earthquake retrofitting

user-7039450 | Posted in GBA Pro Help on

I am trying to order some Simpson retrofit foundation plates and can’t figure out what o.c. Stands for in the table that tells you anchor bolt size, diameter of screw

Here is the context:

Anchor bolt o.c. spacing

Also in the chart that tells you allowable loads DF/SP (160) there are two columns F1 and F2. Not sure what that stands for

Thank you so much!

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  1. Expert Member

    O.C. is "On Centre". It tells you the spacing of the bolts. So every two feet would be 2'-0" oc.

    DF is Douglas Fir. SP is Spruce-Pine

  2. GBA Editor
    Martin Holladay | | #2

    Malcolm is correct. In Canada, o.c. stands for "on centre."

    In the U.S., however, o.c. stands for "on center."

  3. GBA Editor
    Martin Holladay | | #3

    Below is an illustration that shows what F1 and F2 refer to.

    The illustration comes from this Simpson catalog page: "Retrofit Foundation Plates."


  4. GBA Editor
    Martin Holladay | | #4

    You may want to read this Simpson guide: "Seismic Retrofit Guide."

    On page 18, you'll find the handy guide to abbreviations shown below. On page 17, you'll find a glossary.


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