http://www.afswall.com.au/index.php/news/2-uncategorised

 

Looks like an Australian product. I was hoping to not buy forms, due to cost, and the fact that most of the concrete we do is cut up infrastructure stuff, lots of angles and wing walls.

 

I have built a lot of walls out of 3/4 that were 16' feet tall. Ties were drilled out 8" from the edge and then 16 oc in the field. If poured at a safe rate the forms will hold just fine. Walls that tall would get 2 kickers per strongback.

 

You can do it with 3/4" form ply. It will be pretty expensive though.
A wall that size.... I would use a double waler system (maybe even up the size of the lumber to 2x6) and place my tie holes at 10 to 12" o. c. at the bottom for about 4 or 5 rows.
How thick is the wall going to be?

 

I would not consider pouring a wall that tall with plywood. I would find a supplier who can rent you some symon forms. Only way to go, imho.

 

I second renting some Symons or the like.

 

Whats the application? That would be a very time consuming snap tie and waler build...
If you have access to a crane gang forms might be a good option.

 

This is a wall on a dam. Its 12 inches thick. I expect the fill rate to be fairly slow. Like I said I like ply because of the cut up nature of our jobs I can use the ply easier. And I came up a carpenter so its easier to do for me. It will run 3800 to rent symons for the first job, but I am bidding 4 seperate projects at the same time though so I figured I could buy the ply for about 7 and it would last me for a few years. But I don't want any blowouts thats for sure.

 

Tie spacing and whaler spacing are all dependent on the height of the pour and thr rate at which you fill the form.

ACI 347 is the standard publication that will give all of that information. I would suspect that the spacing would be fairly close unless your fill rate is very slow.

I keep a copy of the standard in my office .

 

I'd contact EFCO or Symons.

 

Or Peri.

 

Or Logiks (sp?)

 

I've only used 3/4 ply on 24" and less forms.

All other ply forms have been 1-1/8" ply.

Check with the pro form setters, they do this daily and can probably have half the forms set before you are unloaded ....

Definitely worth a call ....

 

To do 3/4 forms you are also going to be buying a lot of 2x4's also.

It's not like you couldn't build the gang forms with e-beams and super studs.

There is also Doka Framax system. they could be build in place then pulled out and used again in gang form. Have done that before. :laughing:

Leave the 1 1/8" panels where they belong on a residential job.

 

In warm enough weather and a slow enough pour rate you could probably do it with a 12' x 12" hole pattern according to ACI. that is a lot of ties. Walls like that you should have a professional design. Are you looking to use plywood because that is the system you own?

if it only the two walls, It hardly calls for a large gang system unless you already have one. they are the best in repetitive situations.

 

Like I said I have done 3/4" form walls that were around 30'-32' tall. We built the walls 16' for the first pour. Then jumped for the top pour. All with the standard 16" layout. To do stuff like that you need good carpenters and pour team.

I prefer a good jump deck system but you know. You build with what you got and you do it good. :thumbsup:

 

This is all 3/4 plyform. You can really go how high you want as long as you brace enough and your vibrator is long enough I suppose.

 

I agree you can go fairly high with ply, I have done 8-9' house wall no problem with walers though. Look at how Hungry Horse dam was done. Nothing but 1x lumber with walers and that is a pretty big dam. Or for that matter concrete elevators done with 1x slip forms. all in the design and bracing.

 

MEVA light panels the fastest way to go. They strip the best and can be hand or crane set. I would gang a wall that size and crane set it. Efco or doka are good options also. At minimum symons panels but plywood is a no no. It can be done but too $

 

Problem with the form systems is it will bust the bank for the project, its pretty much a guaranteed lost bid. Seems like that pictures says alot, but then again it could have blown when they poured it. Also we live in Montana, the design is the shapes drawn on the paper there is no pour or form or calcs supplied.

 

Pretty sure it didnt blow out.
This pic was taken right after the last form was removed and before we cleaned off all the "boogers" and whatnot from the forms.

 

Its not a bad thing to lose a bid sometimes

 

We win about 1 out of 8, but on a 120k project buying a set of 30k forms its just a waste of time if your trying to price it into the project. I have lost the last 3 bridge projects by less then 4 percent, I don't have to be overly cheap to win. Im just doing the proper due diligence before I price it.

 

When I mentioned EFCO or Symons I meant renting, not buying. I know EFCO also sells reconditioned. I've seen used forming systems on Ebay too.

 

Worked concrete for a major construction company for 8 years. I've worked on bridges, dams, buildings and a few other challenging projects. I suggest renting symons or peri, or something similar. The cost difference between form fabrication and labour won't be much different than the rental fees. Plus with a system such as symons, they're much more versatile. Is it a small dam? Most dam jobs I have been on have a crane, which may make it a little easier to move material.

 

Unfortunately there won't be a crane, its very remote, we have to build a make shift road in and out. We are bidding the general contract. So you think that the savings from using Symons on labor would outweigh the plywood? Thats probably pretty close. And Symons forms are going to be stronger in the end right? It is relatively small yeah. 16FT high by 90 ft long with a 12 inch thick wall, then backfill behind it and 8ft tall by 50 foot wall at the bottom and a spillway that goes between.

 

So that was 3/4 form ply? And is that a 9 or 10 inch pattern?

 

3/4, I dont remember the spacing. I want to say 12" but dont quote me on that.

 

Unfortunately there won't be a crane, its very remote, we have to build a make shift road in and out. We are bidding the general contract. So you think that the savings from using Symons on labor would outweigh the plywood? Thats probably pretty close. And Symons forms are going to be stronger in the end right? It is relatively small yeah. 16FT high by 90 ft long with a 12 inch thick wall, then backfill behind it and 8ft tall by 50 foot wall at the bottom and a spillway that goes between.

I don't have much experience with form ply builds, other than building odd ball fillers or single formed walls. But I would guess the labor savings would be tremendous. Plus scaffold brackets hook right to the forms.