How Much Rebar in Pond Masonry Wall?

[zeuspaul]

I'm building a koi pond. It is dug into the side of a slope. The outer wall is about thirty feet long concave inward. This outer wall will be about five feet high and built of 8 x 8 x 16 concrete block and then waterproofed.

The wall will be backfilled about two thirds of the way. The upper two feet or so will have no support from the earth.

Should I run lateral rebar in every course? Two twenty foot sticks overlapping ten feet in the center? Or can I get away with rebar in every other course? I'm planning on using 5/8 in rebar. Would 1/2 be adequate?

Does the bottom course need rebar? It will be backfilled with concrete.

How often should I drop vertical rebar? Every third hole?

Thanks

Zeuspaul

 

[HappyCPE]

You should run "Durowall" or galvanized masonry wire reinforcing horizontally every other course.

Vertical rebar typically would be every 3rd cell [24" oc] with #4 or #5.

If this is holding back earth you should consider going with the heavier wire and rebar or using wire every course and #4 every other cell. YMMV!

On edit: The website below has some interesting seismic stuff, since you're in California, but I'm not sure of the applications. I would cut and bend the wire reinforcing to the curve of the wall, and overlap the ends. Also, if I am imagining this correctly, the curved wall will have a lot of force channeled into each end - you should consider doing some heavy piers at the ends, filling all the cells with concrete, to anchor the thing. Think of your wall as a sideways arch.

Dur-O-Wal Single Wythe Systems