New foundation

[Robert_in_NY]

I thought I would share this with you guys. This is a foundation we are working on for a local machine shop. The pit is 8.5' deep and is roughly 30'x30'. While I didn't get to remove the old foundations and concrete I do get to form up the new section and rebuild the rest. The form walls are 4' high and it is 20.5' x 19.5' at the widest points. We are installing 38 pockets for the tie downs that hold the new machine. We will also pour a new floor around the edge of this foundation and pour new walls leading up to the existing floor. This is what we did the first day.

 

[Robert_in_NY]

This is after the foam and 5/8" rerod was put in, we started backfilling so when we add the concrete the form won't blow apart. The form is staked down along the outside every 3'. It will take over 50 yards of concrete to fill just this one section.

 

[MikePA]

That entire area surrounded by the green boards will be filled with concrete???? /w3tcompact/icons/shocked.gif

Do you have to do that in multiple lifts?

 

[Robert_in_NY]

This is how we left it today. 36 of the pockets are formed in with two more left to do when we start to pour. We will have a pumper truck which the cement trucks will empty into and will pour the entire foundation all at once working around the pockets. We will add a lot of weight to the pocket forms to keep them from rising but it needs to be done all at once for strength. I will try to get pics while it is being filled but I will be backfilling the rest of the way at the same time so it will be busy. Once the foundation is done we have two more pours to do, one for the floor around it and another to build walls up to the ground level floor. This is similar to two other forms we did recently for this company but this is the largest of them all. I do enjoy these types of jobs so I thought I would share with others and will gladly answer any questions.

 

[Thomas]

Holy{King Tut Tomb}smokes /w3tcompact/icons/shocked.gifI guess if your going to do it right,do it right the first time..50 yards /w3tcompact/icons/shocked.gif

 

[Robert_in_NY]

We had one problem with a different foundation a few years back. The prints were not right and ended up placing the pockets in the wrong locations. It wasn't our mistake and the owner realize the prints were wrong after the forms were off so we had to drill and chip new pockets. Monday we will go over all the measurements and calculations with the owner and make any adjustments or alterations before the concrete goes in. The prints come over from Japan and are converted over by the pencil pushers in the office at the plant so they tend to make mistakes when working with all these measurements so we are already working on our third set of prints in 4 days. The machine that is going on the foundation weighs 43 tons so we do not mind taking our time to get it right. Take care.

 

[Soundguy]

Only 86 thousand pounds.. and you need a foundation footer like that? How much vibration is this machine going to be putting off? Is this for torque specifications, or lift operations?.. I'm interested ( civil engineer ).

At a little over 2 tons ( ~4200 lbs ) per yard ( depending on psi of concrete, water content, agregrate, and fibre mixes, etc ) ... thats over 200K# on concrete.... I gotta ask.. whatch holding down... a bridge pylon?

thanks,

Soundguy


"weighs 43 tons so we do not mind "

 

[frank_f15]

very interesting!!! what kind of machine is it? and who is doing the hauling and setting it in place?

 

[Robert_in_NY]

I am not sure of the spelling but the machine is a Karaki. It is the third boring machine they are putting in. It is brand new and we are doing what the manufacturer calls for. The machine has the tool carier built in and is completly automated. They do not want the machine to be affected by vibration from itself or any other machines or equipment in the building. We are using a 3000psi mix and as you know these machines are expensive so it is better to do it right and eliminate any possibilities while you are building it before hand. When it is installed it should be able to withstand anything which is what the owners want. This is the largest foundation we have done yet as the other two were smaller versions. This machine when installed is suppose to work in the thousands of an inch so it does not want to have any movement. I hope I answered some of your questions, we are pouring tomorrow morning and the machine will not be installed for another month or more till all the concrete is cured fully. This mix is a 28 day cure so hopefully in a couple months it should be done and installed.

 

[Robert_in_NY]

I do not know who is installing it but it is a Karaki(sp?)

 

[Soundguy]

Well.. those were the two ideas I was suspecting to hear with that kind of footer... built to torque specification, and for a specific vibration isolation rating... I was guessing 2-3k psi for the concrete, and use as a dead weight rather than a weight bearing situation which might have needed 16k-20k psi concrete.

One question. Will there be any isolation structures used to seperate the machines slab and foundation from the sourounding slab? (Rubber or fiber expansion joints?) etc? If the top slab is continous.. I'm wondering about standing waves....

If your interested.. you're pouring about 210k lbs of concrete into those forms, if anyone asks... useless trivial knowledge.

Soundguy

 

[Robert_in_NY]

There is a 2" foam board ran around the entire foundation which can be seen in one of the pictures I posted. This seperates it from the rest of the building and the other floor and walls we will build. We finished the initial pour today. It took 2 hours to pour 46 yards of concrete total. We will remove the forms in a couple days and start forming for the second pour which is a floor around this foundation. As for the weight of the concrete I figured it to be quite a lot. We also added 42 tons of 1&2 stone to help backfill around the forms. We just got another 20 tons of crushed gravel for leveling the ground for the 2nd pour. We will probally have another 20 tons or so of crushed gravel dropped before we are done with the final pour. I took some more pictures of the pump and what we ended up with today and will post them later when I get them on the computer. Later.

 

[Soundguy]

Is foam then going to be used as the expansion joint for the top monlithic slab? or will there be wood/fibre/rubber joints ( surface only ).

Soundguy

 

[Robert_in_NY]

Our floor will sit level with the foundation allowing the foam to be the barrier there. I am not entirely sure yet what the plans are for the rest but I will let you know when we start it in a couple days. It is up to the bosses to decide as they have to live with it. This is the first foundation that we have recessed into the ground as all the rest have been done at floor level which makes things a lot easier. I am learning a lot on this project which makes it fun. Take care.

 

[Robert_in_NY]

This is when we started filling the hole. It took about 1.5 hours to fill it and another half hour to clean up the pump.

 

[Robert_in_NY]

This is a view of the pumper. Nice little machine.

 

[Thomas]

How many yards did it take?

Cement pumpers sure save a lot of wheel barrow time. /w3tcompact/icons/wink.gif

 

[Robert_in_NY]

This is when it was full.

 

[Robert_in_NY]

It took 46 yards. It is the first time we used the pumper and all of the other foundations were wheel barrowed over to the hole. I don't complain though as it was good exercise and it isn't hard to wheel on concrete. Take care.

 

[RonL]

Robert

I'm very much interested in how the pumper worked. I have done concrete work but have absolutely no experience with a pumper. First off, was it worthwhile? Is there a reaction at the nozzle end like on a fire hose? How hard is it to move the hose to the various pour points? Did you rent the pumper? Sorry for all the questions.

RonL