Upper Walls Poured!
On Tuesday we had great weather. It was the day of the big pour. After prepping for the last couple of weeks we were ready to fill the forms with concrete for our on-farm butcher shop. The big day was here!
Construction is often like this – you prep, prep, prep and then there is some big event like pouring concrete, putting on the roof, etc that all of a sudden changes everything leaving you with a sense of accomplishment. During that prepping time it can feel like it is going on and on without great progress but all those little steps must be made so that we can have a boring pour. Excitement is the last thing you want when dealing with 200,000 pounds of liquid rock.
Pumped! – The Movie!
The above YouTube movie shows the pump truck unfolding like a preying mantis and the beginning of the pumping of concrete into the forms. I’ve sped it up 16x as the reality is much slower and safer. The result is we look like a bunch of Keystone Cops. Let the movie load fully before watching it for the best viewing experience.
Things to watch for:
- Pigs – See if you can spot any pigs.
- Count the Crew – How many people do we have working to make this pour. Details later.
- Wind – We live high in the mountains, at least high for the east coast. We pretty much have continuous winds. You’ll notice the brush and trees shaking. The pump truck is shaking quite a bit too. That’s a lot of wind catcher up there.
- Swaying Pipe – Catch it if you can! I was holding the hose at the output end and keeping it from shaking too much. A challenge.
- Dave – The pump truck operator in the green cameo coat with his remote.
- Snow – Look at the mountains in the distance. Fortunately most of the snow melted by noon when we started pouring.
- Whey Driveway – That is what is directly in front of the camera. This is how the whey trucks drive up to the whey tanks so we can use gravity feeding – no pumps there.
- Form Work – They look small on the west uphill side, just 4′ or so but are 13′ high or so on the east side because the building is set into the hillside. This gives it a low profile. In the end it will look like one more barn along a back country road.
- Insulation inside the forms is integrated into the concrete pour to give super insulation and high thermal mass to save energy.
- Spot the Pumpkin
- Clouds – Since the movie was sped up so much the clouds are rather dramatic, racing across the sky.
This concrete pad is the sub-slab of the lairage which is the area the animals stay the night before slaughter. It is just outside the actual abattoir. The surface is rough because we’ll be pouring the rest of the slab next year. This sub-slab pour covers our insulation, pipes and such.
We used 25.25 cubic-yards of concrete in this pour. The concrete we’re using weighs about 4,000 lbs per cu-yd so that is about 200,000 lbs or about 100 tons of concrete. [Edit: Actually it was 200,000 lbs that I was thinking of for the whole wall height. There is 100,000 lbs in this pour plus 100,000 lbs we had poured in the walls before. Thanks to those who caught that slip of the fingers!] In just the walls we plunked down twice the weight of our tiny cottage. This pour also cost more than half as much as we spent to build our entire cottage. This makes sense as the butcher shop is about five times larger than our house and even more ruggedly built although it is constructed along the same design lines as our home.
Top of the Pour to You!
When we were all done we pulled the concrete off the form headers and cross braces, mounted it up, stuck in more chunks of granite and drew a key line down the middle. This will be where our next stage up ties in when we begin pouring again in the spring.
Our concrete mix was 3,000 psi with a 5″ slump and 3/8″ aggregate. We used Super-P water reducer and fiber as well as the rebar which helps with crack control in very thin areas. The concrete also had hot water in it as we’re pouring after October 31st – Halloween special. It was just barely liquid enough to make it into the tight parts of our forms with some poking, shoving and vibrating. It took us two hours to pour and by the time we got the last concrete in it was already setting up as three of us quickly went around the top with spatulas and floats. No time to lose.
Tops of Walls Covered in Burlap
Actually, no, the hot water is to keep the concrete warm so it will cure. Since we’re pouring into insulated forms this is even more effective. Curing is also exothermic – generating heat. We added covering to further help the process. Concrete is not dried but chemically cured, a process that goes on and on and on. In a month it will be up to most of its strength.
The way we worked was I started out up on the forms with Ben and Will spotting me from the ground. They also watched the forms for any problems. Ben was outside watching the exterior of the forms for any signs of potential blowouts.
Dave, the pump truck operator hand his chest mounted radio remote control with which he played with his big toy truck. Some guys get all the fun toys.
The concrete truck drivers delivered three truck loads to the hopper on the back of the pump truck – one of the trucks was pink but it never shows in the video.
Ben is cracking the threaded tie rods free of the concrete matrix after the initial set of the concrete. We will continue to do this about every 12 hours, then 24 hours, then 48 hours until the concrete cures from green to white. This makes it so that we can retrieve most of the rods at a later date to reuse them on another pour.
And a boring time was had by all. Hallelujah!
Outdoors: 40°F/22°F Partially Sunny, Flurries
Tiny Cottage: 65°F/61°F
Daily Spark: Jack of all trades and a master of many.