Pouring steps down to the creek/swimming hole...nope, never done it before!

[2manyrocks]

Looks like the OP would either need a crane or would have to set some temporary beam with a hoist to use a tremie?

If he isn't going to place wet concrete at the base, I suspect he'd still need something similar to set a similar sized huge rock.

Or maybe it won't rain during the month of August and the water levels will drop.

 

[MotorSeven]

I think a Tremie is out. I deleted the pad in the creek for the one by the swimming hole dam....it just stuck out too far in the current. The last tread is sitting on the end of the rip rap, so I think I can dig a pretty good hole there to fill with crete.

Here it is with the blow out forms all done, and all that is left is the rebar:

As for the blow out prevention, I bucket-ed up sand/rocks from the creek to fill in any gaps below the OSB.

 

[ultrarunner]

Any idea how many yds of concrete required?

I need to do similar on a downslope but no water or creek issues.

 

[2manyrocks]

Concrete calculator for stairs is at the bottom of the page. Concrete Calculator

But the OP's stairs look really, really, deep to fill with concrete.

 

[ultrarunner]

Concrete calculator for stairs is at the bottom of the page. Concrete Calculator

But the OP's stairs look really, really, deep to fill with concrete.

Im thinking the finished weight will be considerable...

 

[Streetcar]

I would add more support of Osb . There will be a lot of pressure from concrete on forms.
on side note bottom of riser is typically cut at 45 degree angle to aid finishing tread

 

[Streetcar]

Im thinking the finished weight will be considerable...

guessing finished weight will be between 4to5 tons

 

[MotorSeven]

I calculated between 4-5 yards, so 7,000 +- Lbs each. As far as blow out protection, all I did is to stake it where possible due to hitting rock everywhere else. If you think it will help, I can add 2x6" vertically screwed to the sides of the stair tread down to the ground/rock every few feet. We will set large rocks against it when I have some help right before the pour. Maybe I can cross brace things horizontally from other rocks several feet away in some places.

I have asked for a wet mix when filling basement block, so I assume I can get a dry mix? A thicker pour would help contain it, but shorten working time, so we will have to hustle. What I want to try, is to pour only half way up, then move the truck to the other staircase and repeat. This will give it time to set up a little before filling to tread height.

I did not do a chamfering edge in the form, so will just hit it with the edging trowel instead.

Yes, the one next to the pigs is the taller one by a good margin & is worrsome. The rip rap under it is huge there, with lot's of voids going down 2-3'. Bucketing gravel in those voids is slow work, but it does fill them up. Working on it Sunday, as it's pontoon time on the lake today and tomorrow.

 

[2manyrocks]

What is the temp and humidity you're working in? The heat index in Middle TN is supposed to be 105-106 today.

 

[ultrarunner]

I added a couple of lengths of threaded rod to keep my stringers firmly in place…

 

[MotorSeven]

What is the temp and humidity you're working in? The heat index in Middle TN is supposed to be 105-106 today.

92 today @ 53%

I added a couple of lengths of threaded rod to keep my stringers firmly in place…

Not a bad idea, so you just cut them off when done? How to keep them from rusting?

 

[2manyrocks]

Concrete snap ties are made to keep forms from spreading during the pour. Once the concrete cures, they can be broken off and leave a hole to be filled later hiding the tie.

 

[Streetcar]

Order low slump concrete (2 or less)and pour slow.
I would add both external 2x6 and internal form ties. The internal form ties should have large washer against the wood forms to prevent the ties from pulling through the forms
concrete will be pushing around 150 pounds per cubic foot against forms

 

[MotorSeven]

Yikes, internal form ties might be hard to find in time. I might have to resort to a 1/2" pvc pipe and all thread/washer.

Info is appreciated///

 

[MotorSeven]

We pour today. Finally got in touch with my neighbor who has been a concrete guy most of his life. He inspected the forms and made recommendations to beef them up, like those on this thread have already done. We were in the process of doing that when he arrived. He thought a 4" Slump mix would be about right for this pour. Since I know that means thicker than normal, I didn't know what it really meant. His description:

Picture filling a traffic cone with cement, then turn it over on the ground & remove the cone. A 4" slump means that the wet crete will bulge out of its cone shape by 4". A 0 slump would have the cone shape not bulge at all, while a 10 slump would result in a large puddle of mud.

He also cautioned the use of a vibrator for this type of pour, and thought that tapping on the forms lightly would be a safer bet in preventing blow outs. Since I don't care about minor void imperfections, I nixed the vibrator for today.

Hard to tell in the pic's but the staircase next to the pigs has a lot more volume, so it appears taller due to the terrain. He thought that filling to less than 50% of that form first, then moving to the other staircase might be wise. I think it's a good call, so wish us luck.

 

[2manyrocks]

Good luck.

 

[lilranch2001]

You have chosen a very challenging project, but with a little luck, and a good accomplice it may pull off very well for you. It sounds like you have listened to to a lot of peoples suggestions and come up with good solutions to your issues.

Good luck today!

 

[MossRoad]

Didn't see any rebar in any of the pics...

Hope you have plenty.

 

[MotorSeven]

The pour went...ok. The only problem was almost a fatal one....5 old bastages don't move fast enough and the 4" Slump started setting on us in the middle of pouring the second staircase. We also certainly could have used a vibrator, and I kick myself for not going and picking it up to at least have on hand.

We started on the higher volume staircase with the intent of pouring it half full, letting it set a bit, while pouring the lower volume one. It was immediately apparent that the mud was so dry that we knew the forms could handle the full pour, so we went for it.

We left a man on the 1st one and moved to the 2nd. A few steps up, we had the driver pause while we leveled things off. 10-12 min went by, and when he tried to send us more crete down the chute, it was stuck in the hopper. We took a shovel party to it and got it broken up, dumped that off to the side and continued filling. The driver said we had to hustle as he could feel the mud curing in the Mixer. So we went with no huddle and got the form full.

I was off by about a yard and a half, so we had left over to put across the top of the rip rap where the water current is strongest(in front of the short leg of the pig wall). As the mixer rotated, I could hear the load banging one time per revolution....but it came out and was spread ok.

It was then a mad dash to get the steps edged, which was a pain in the .....!*#(yes, champhering strips would have been way better)
All in all, I don't think we could have moved any faster. Pulling the forms off today, and loading pics now.

We started at noon 15 and quit at 2:30.

 

[MotorSeven]

Didn't see any rebar in any of the pics...

Hope you have plenty.

We put 50' of 1/2" in each form....could have used more since there was plenty of room.