I think my second favorite pattern is the Yorkstone Slate. There are a ton of tools in this set and they fit together in increments. Each tool is separate, so no two jobs are ever identical, because it is almost impossible to duplicate the set exactly. They start at 6" x 12" and go up to 42" x 42". The colors used can drastically change the look from sandstone to slate. If you go in and hand tint, it is incredible. We used this pattern for an historic restoration project on the Marland Mansion in Ponca City. It was an awesome job.
Just so you don't think my job is all sweetness and light, there are some serious hazards to being a FPCF. One of these hazards is the dreaded concrete pump. We *hate* the pump. It is a dirty, dangerous piece of equipment. Unfortunately, sometimes we simply have no choice but to use one. This project was the roof of the library at Tulsa University. There was no way we could get a mixer to it, and we couldn't hardly expect our poor crew to wheelbarrow 14 thousand square feet. Talk about murder by concrete. Here is a picture of a concrete pump.
In order to use a pump, you must first prime it. This means you have to order a yard of grout from the concrete company. Grout is basically watered down concrete without any rocks, and it sort of greases the inside of the hoses to make the concrete pass. Sorta like those fiber pills my DH chokes down! HA! Anyway...after you have lubed the hose, then you start pumping the concrete through the system. This is great, until you have to stop. On this particular job, we had to stop a lot, since the pours were all 8 foot by 8 foot. Now every time you stop the pump, you risk a clog. Then you have the excitement of running up and down the hose with a sledge hammer pounding on it, trying to break up the clog. If this doesn't work, then you disconnect the hoses piece by piece till you find the clog and dump it out. Unfortunately sometimes there is a defective hose, and when the pressure builds up, it can explode. This actually happened to us on the TU job. I shudder to think what would have happened if any of us had been standing next to that hose. It shot rocks at least 75 feet, and was so explosive that concrete actually wrapped around the round light fixtures. It was terrifying, and gave me a whole new respect for the danger involved. I have no doubt that it would have been deadly had anyone been any closer than 50 feet.
At the end of each day, you have to take the hoses apart and wash out each section. What a pain! Not to mention the monumental mess the pump itself makes. It spews concrete everywhere, and guess who gets to clean that up? Certainly not the pump jockey, or the mixer driver...
FIRE!!!
Ok, not really. This is one of the reasons I don't mind getting up early. 
If I wasn't a FPCF, I would miss out on sunrises like this!
7 comments:
I want my kitchen floor to be like that last concrete you did--with the different sizes. I love that!
Are you saying you won't come here and do it?
LOL I would love to come do that for you. Dragging the DH along would be another matter completely.
I do know of another FPCF. She owns a company in Kelowna, British Columbia, Canada. The company name is: Silver Springs Ventures. Her Name is Connie Crissler. Her email is: connie@concreteteam.com
She is a very driven businesswoman, and she knows her stuff. Her business has expanded so much that they have 2 concrete pumps, a truck-mounted line pump, and a 38 Meter boom pump - both Concords.
I'm very impressed with your shop - and the concrete work around it and your home, a nice way to dispaly your handi-work, which is top-notch stuff. BTW.
I an a member of a concrete pumper's forum, if you'd like to check us out, go to: www.concretepumpingadvice.com
We can likely give you some tricks of the trade to make your pumping experiences a lot easier. BTW, short breaks in pumping shouldn't readily cause plugs. A concrete pump is a good quality-control machine, there is a very slight difference in mud that pumps or not. Hope to see you there!!
Speedy
Hi Speedy :)
There are a few women in the construction business. Most of them are pretty tough!
We aren't a big company, just a small family operation, but we have been doing this for a long time, and are proud of our work.
I am not very driven. By the end of the day, I am almost too tired to drive home ;-)
We rarely use a pump. The problem on this project was two-fold. One was the way it had to be poured, which caused frequent stopping, waiting and then re-starting, and two, a pump jockey that either didn't know what he was doing, or was not paying attention. I couldn't believe the force of the explosion. It was not fun. We were using a pump friendly mix, as well as retarder, and water reducer, but when it is over a hundred degrees and you have to stop and wait so much, you are going to have the occasional problem.
I will point my DH to the pumper website. He is the one who orders the mud :-)
Good, I hope to see him log in, and ask us a couple questions and share his experience as well.
As far as the 'hose-whipping' or 'explosive release of air' incident you described, I would place more blame with the mixer driver, he let the level in the hopper get too low and the pump took in a gulp of air and the air was pumped through the system. (it's a simple job....keep the hoper filled with a conststant level of concrete. I doubt that you were pumping faster than about 30 yd/hr while the pump is stroking - and that's maybe 1/4 of the time?)
The air gets put under the same pressure as the concret, and shrinks in volume, until it gets near the end of the hose, then it wants to get back to normal atmosheric pressure, and it can push the concrete in front of it out VERY fast, as you saw. It is stored energy. Ideally, the system has nothing but concrete in it and as we know solids and licuids are incompressible (wet concrete is actually considered a fluid, that's why you can pump it. When the pump stops, the concrete stops moving. If there is air in the hose, there is also stored energy!!
This PDF: http://www.concretepumpers.com/pdfs/Hosewhip_Bulletin_FINAL.pdf explains this very well. The ACPA (www.concretepumpers.com) would likely send out a DVD and a number of pamphlets that you can share with your crew.
You should ask if your pump company is a member of the ACPA and if they have ACPA certified operators. If so, they have access to all knds of safety material for mixer drivers, operators, concrete placers.
Sorry to be so long-winded, but you described a serious situatuion, I'm glad that nobody got hurt, just dirty, it most definitely is a dangerous machine if care isn't taken.
I think we are talking apples and oranges here. This was not an air incident or hose whipping, a section of the hose exploded. I have picked concrete out of my husbands belly after an air incident, and this was completely different.
The hopper was full during the entire pour. I know this because I was the one putting the admixtures into the mixer. The system had clogged, and the operator kept pushing, trying to shove the stoppage through. There was apparently a defect in the hose that would not show up during normal operation. We had about 240 feet of 3" system on, and instead of stopping and finding the clog, the operator pushed. Needless to say, when the hose gave way behind the blockage, the pressure shot the concrete everywhere. The section of hose that blew up was about 4 sections in from the boom. The clog when we finally found it was about 6 sections from the open end. We uninvited this particular operator back.
We pumped 60 straight days on this job, and that was the only real incident we had, other than occasional blockages. We had to live with the blockages because the pours were 8' x 8', and we had to stop pumping to move to the next 8x8 or disconnect system.
This pour was really difficult, with no other options for a boom, due to existing trees, and very restrictive access for the mixers. It was totally different than the usual pump pour, like footings or large slabs.
A good pump jockey is a great asset to a good pour. We appreciate them, and do everything we can to make their job easier. Sometimes, you just get a guy who would rather be doing something else, and that can be dangerous. Fortunately for us, this time, nobody was hurt, and the damage to the building was minimal.
I am just glad that most of our pours don't require a pump. I am a weenie and they scare the bejeebers out of me on a good day.
Thanks for all the helpful information :)
Your welcome for the info....I like to assist if I can. Pressuring a plug through is NOT the right way. All that hammering with a sledge takes it's toll on hose....it tends to break the reinforcing fibres, as you can attest.
The RM plant needs to make a better pump mix. 10 minutes of sitting should not cause a plug. Flyash is a great boon to a mix's pumpability. I'm sure you'd rather ante up another 5 to 10 dollars per yard for a safe, pumpable mix. It would pay back in the time saved fighting. Plus if you know the price up front, you pass it on....
Hope your future pumping goes better.
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