Good Omens

OK, maybe it's not an omen for things to go well, but we had a pretty good day on the concrete front.

To start off, Noel wrapped the Stupid Pipe in cardboard. This was a last-minute thing and mostly a waste of time. Not only will we never have to deal with that pipe -- it's the Stupid Pipe, not the house water supply, which was well protected under soil and gravel at the bottom of the trench -- but if we were going to wrap it to be able to pull it out then we'd have to have done a lot more excavation and wrapping work. Sure, the cardboard will make it slightly easier to get the pipe out, because the concrete won't get too far into it in the middle. But the ends will be good and sealed in there. Well, if somebody ever breaks the wall apart they will find something weird to puzzle over.

Right on time, the concrete truck pulled up. Our driver was terrific, and since we had never done this before walked us through the process and how he wanted us to signal him. Plus, he was right on top of what was happening and prepared to move and adjust the truck as needed. Yay for Right Away Ready-Mix.

The thing about a project like this is that if you want photos during the process, you either have to be willing to risk your camera to the concrete splatters, or you need three people. Because one person has to direct the chute, and one person needs to vibrate the concrete into place, and that leaves no hands on the camera for blog posts, what a surprise.

Anyway, we got the concrete into place pretty quickly. The concrete vibrator was great for liquefying it just enough to slump it into place. Then it was just a couple of passes with the vibrator to shake out the air bubbles.

I tried to capture the process of bringing up air bubbles, but it was pretty subtle. In the wake of the vibrator you can see some shallow lumps, some of which have black holes in the top. Those are air bubbles, and the holes are where they have popped and are deflating. Very subtle in photographs.

When the whole thing had been shaken free of air bubbles, Noel went around and adjusted the rebar that had been knocked around quite a bit during the process. We then wedged it into place with wooden stakes and so forth.

An architectural historian once told me he wished everybody who ever did any concrete work would carve their names and the date into it for future dating advice. So there you have it. We considered trying to do a pet footprint, but there was such trauma when we did that on the metal shed foundation out back that I decided it was not worth it.

Now that the footing is in it looks less like a weird water feature and more like a wall is taking shape.

The concrete truck driver told us we had a charmed job: we'd estimated the amount correctly, we listened to his advice on how to signal him, and the weather held out, too. It was a pretty good placement, and makes me a little more confident about doing the stem wall part in a week or so.

posted by ayse on 03/07/11