I am in the process of pouring an 8" thick 36" high concrete retaining wall for my new WW shop. This wall is 80' long and returns 30' across one end. The wall sits on a 24" footer with plenty of steel. Every 4' or so there is a #4 rebar cast into the footer and extending up into the wall forms.
The building will be post frame construction and one wall will sit directly on the 8" concrete retaining wall. Every 8' we have positioned a 4" steel channel to be cast into the concrete in a vertical position. The purpose of these channels is to extend above the wall about 2' and hold the 16' wood posts (using bolts). (The posts for the other two sides of the building will be installed in the earth as in typical post frame construction). Each of the steel channels has 5 holes cut with a torch and #4 rebar goes through each of these holes. The 5 rebar extend for the entire length of the wall and are each tied to the rebar cast into the footer.
Because this wall is critical and supports one wall of my building, I want to do the best possible job and want to specify the optimum concrete mix. We want something that will flow well around all of this steel and have excellent strength and finish. We may not actually rub the wall out but we will definitely use a vibrator. We are set to pour this wall on Friday.
So WOODWORKERS, there must be some engineers out there in WW land that can tell me what concrete mix to use for this wall. Example: 4000 psi, 5000 psi, pea gravel, 1" aggregate ....etc, etc. Thanks for any concrete expertise you care to offer.
Rob