Hi Bruce,
First, there are two things to consider with decks supported on masonry piers: 1) are they attached to the house in any way; 2) are they free standing and not attached to the house in any way.
If attached to the house in any way, then the pier footings are required to be below frost level just like the footings for the structure. With the deck attached to the structure, the structure will provide some lateral support and bracing.
If not attach to the house in any way, then the pier footing are not required to be below frost level. However, with the deck now completely free standing and receiving absolutely no lateral stability from the house, the deck itself will need to be designed to provide its own lateral support to resist leaning, twisting and other affects of loads trying to move the deck. Those other loads include occupants moving across the deck and moving about on the deck.
The masonry piers will need to be constructed in accordance with, including limitations on their height:
- From the 2006 IRC. (underlining and bold are mine)
- - R606.6 Piers. The
unsupported height of masonry piers shall not exceed ten times their least dimension. When structural clay tile or
hollow concrete masonry units are used for isolated piers to support beams and girders, the cellular spaces shall be filled solidly with concrete or Type M or S mortar, except that
unfilled hollow piers may be used if their unsupported height is not more than four times their least dimension. Where hollow masonry units are solidly filled with concrete or Type M, S or N mortar, the allowable compressive stress shall be permitted to be increased as provided in Table R606.5.
- - R606.6.1 Pier cap. Hollow piers shall be capped with 4 inches (102 mm) of solid masonry or concrete or shall have cavities of the top course filled with concrete or grout or other approved methods.
The piers which are tall enough to support a deck would exceed 10 times their least dimension and require being filled. Additionally, for a deck with an height below it of 8 feet (96 inches) the minimum masonry unit size would be a 10 x 10 inch unit, a 12 x 12 inch unit is a more common size. The piers would also have to address any and all loads, including uplift, overturning, sliding, lateral stability, etc., just to name a few. It is most likely that the pier would need reinforcing steel in it, and quite likely that it would need multiple reinforcing steel bars vertically to attain the stability required, most likely 4 vertical bars with hoops to hold the bars in place, making it into a free standing column with the masonry units acting simply as a form for the concrete/grout used to fill them.
There would also be required to be an embedded anchor bolt or other attachment as is required by the code as related to your specific area, likely a minimum 1/2 inch embedded anchor bolt.
Can anyone suggest a specific reference that defines how a wood deck should be connected to a brick masonry column?
Short of being able to link an ACI 318 or ACI 530 reference on the internet, go here (note: place cursor over link, right click, select "Open in New Window" -
http://www.awc.org/Publications/DCA/DCA6/DCA6.pdf ), scroll down to page 9, scroll down to Figure 12: Typical Footing Options, the right footing with the embedded anchor, and make that footing taller vertically into an 8 foot high column, with the embedded anchor bolt being used to anchor the directly to the deck instead of through an intermediary post.
Does this provide sufficient information for you are should I try to find something more specific if possible?