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Under plates grout

Under plates grout

Under plates grout

(OP)
The metal plate has about 10mm vertical spaces underneath it, is non-shrink grout or epoxy better filler or what other materials can be used to fill it that can take load that can go inside the 10mm spaces?

RE: Under plates grout

What is the area of the plate? How much load? Are you going to grout in place or is lt going to be able to be lifted and set in grout bed? Can shims be used instead? What is the plates sitting on?

RE: Under plates grout

Sika 212 non-metallic, non-shrink grout. Check the product specs to ensure it meets your requirements, but I love that stuff...

RE: Under plates grout

(OP)

The plate is just thin long 40mm angle bar where you support those decoration accent bar frames you see outside building, the load is just very low not even 8kN. It's sitting on concrete. Just need to fill in the 10mm space with something that won't shrink. Would there be a good substitute for non-shrink grout? would epoxy work since these have lower viscosity than non-shrink grout?

RE: Under plates grout

Look into using a flowable grout...

Dik

RE: Under plates grout

Non-shrink grout is your best option. There is really nothing readily available that does as good of a job or is as easy to install as it for the application you are talking about.

Is there a specific reason why you want an alternate product?

PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

RE: Under plates grout

Sika 212 non-metallic, non-shrink grout. Whatever you do, you need to use a purpose-made product. I've not seen an epoxy product specification that says it is appropriate for filling large areas been two close plates. Why would it ever, when this is what a non-shrink, non-metallic grout is for.

Don't try to reinvent the wheel. Use the grout.

RE: Under plates grout

(OP)
Can non-shrink grout fill in space as small as 10mm? I haven't handled non-shrink grout. Are these wetter or more liquid than concrete grout? It's difficult to insert concrete grout in the 10mm spacing because not all can get inside, this is the reason I was thinking of epoxy.

RE: Under plates grout

CHECK THE PRODUCT SPEC but if I remember correctly, the minimum gap IS 10mm.

RE: Under plates grout

(OP)
The sika site noted minimum gap is 25mm (can anyone confirm). This is why I considered epoxy as it can get in the 10mm gap, well?

http://can.sika.com/en/solutions_products/02/02a00...

quoting from the product literature

■ Minimum application thickness (neat without additional aggregate): 25 mm (1 in).
■ Maximum application thickness (neat without additional aggregate): 150 mm (6 in). Thicker
applications are possible with the addition of suitable aggregate.

RE: Under plates grout

Okay, so I just checked... In keeping with the general screwing we seem to get in North America because of the overall litigiousness around here, we do not have the same specs as I was familiar with in New Zealand.

Sika 212 minimum thickness (flowable) in NZ: 10mm
"" "" in Canada: 25mm (*cough* BS *cough*)

Sika 300 PT (not available in NZ last I knew) minimum thickness 3mm...

Frankly me thinks we are getting the "make them buy the more expensive product" tactic from Sika...

I'd like to hear a TECHNICAL reason why a product is good for certain tolerances in Australasia and lesser ones over here.

RE: Under plates grout

You have to have a flowable grout, and build a dam in which to pour the grout. When it comes out the other side, you have filled the gap. But for only a 40 mm wide bar, and this thing is just decorative, I might just use 10 mm galvanized shim plates at the bolts.

RE: Under plates grout

(OP)
If you just use 10 mm galvanized shim plates, it can rust inside, so better to fill it up either with non-shrink grout or epoxy. I haven't handled non-shrink grouts. Why is its viscosity lower or more flowable than concrete paste? what ingredients made this so?

RE: Under plates grout

We don't know all the ingredients of premixed grout. These materials are proprietary. Don't even think about making it yourself.

What material is the "40 mm angle bar"? I imagine that 10 plate shims, hot dipped galvanized, would have superior corrosion resistance to that of your decorative frames. One disadvantage of the grout is that it is brittle, thus subject to cracking due to impact. But if that happens, you just grout it again.

RE: Under plates grout

(OP)

Please view attached picture of the decorative frame with grills. It's bolted up, so no problem with attachment. There is just 10mm gap in the angle bar connection to the concrete below. I inserted 10 mm rebar but you can still insert paper to a 0.5 gap below the 10mm rebar. So I plan to remove the bars inserted into the gap and just use non-shrink grout, would it flow into the gap?

RE: Under plates grout

Flowable grout will, as I said before. But you have to provide a dam to prevent it going everywhere, and to assure uniform contact. Trying to dry-pack it will probably not work well.

RE: Under plates grout

But Hokie, if this user is in North America, they are violating the manufacturer's written instructions by following our advice... For the same product which Australia and New Zealand specs say 10mm is perfectly fine!

RE: Under plates grout

I've used Sikadur in past... have to re-think this a bit... It recommends 1" also... although I've seen it used for less than half this value...

Dik

RE: Under plates grout

Dik: That's because it works perfectly fine down to 10mm...

I don't know what Sika is up to other than pushing the more expensive option where available, and being realistic about the cheaper option where they don't market the costly stuff. *sigh*

RE: Under plates grout

And just for the record: I still think Sika 212 is the right stuff for this application.

RE: Under plates grout

I've used Sikadur 42 for almost decades...

Dik

RE: Under plates grout

Per Sika US website

Product Data Sheet
Edition 6.19.2012
SikaGrout® 212
Minimum application thickness: 1/2 in.
Typical maximum application thickness (neat) is 2"

Product Data Sheet
Edition 6.27.2012
Sikadur 42, Grout-Pak LE
The minimum void depth beneath the base-plate should be 1 in (25 mm), but 1.5 in (38 mm) is preferred.

RE: Under plates grout

Thanks for checking CVG; So it is JUST the Canadian Sika 212 spec that calls for minimum 25mm?!? Not impressed...

RE: Under plates grout

What are the angles made of, and they don’t rust? Could use stainless steel shims or galvanize them. Why not make a bunch of square 75mm x 10mm thick shims out of the same mat’l.? Then make up a collection of various thin shims 75mm sq., when you have surveyed the gap variation, +/-. Then, in plan, punch a slot in the shims a little wider than the bolt dia. and beyond the center of the shim; it should terminate 15 or 20mm from the solid edge which will be exposed, when installed in your photo; and it should be an open slot at the opposite edge, for installation. Back-off the bolts a turn or so, retightening the bolts should take up gaps of fractions of a mm. Otherwise, leave that gap open to breath, drain and dry. That detail would be a real dog to dam for a flowable grout, and impossible to pack with a stiffer grout.

RE: Under plates grout

dhengr: That's a temporary solution; You're going to get rust jacking between the plates, even though they'd be the same material, the joints provide a rusting site. I've seen this many times in old bridges...

Grout.

RE: Under plates grout

(OP)

Notice rain from outside can get in the bars and rust them that is why I want to put grout or even epoxy in it.

What is sika "expensive option where available"? Are you talking of epoxy or another more expensive sika grout than 212?

To those who have handled non-shrink grouts. How flowable are they? Are they like shakes that you order at coffee shop? I haven't seen such before and can't imagine.

In your experience. When rain gets inside welded iron connections. Won't it rust the inside? Because if the welded connection in the photo got rusted, the whole frame may just fall leaving the angle bar grouted on the concrete edge.

RE: Under plates grout

(OP)

to add the 4th question from the above message, notice the zoomed attached picture of the gap with inserted 10mm bars. Can non-shrink grout flow in between the 10mm bars or should I remove the 10mm bars inserted in the gap? The reason I inserted them is to serve as shim but then a paper could be inserted under the 10mm bars so if I insert thin metal sheet under them and then put flowable grout on the left free end and in between the bars inserted, the question is whether the grout would flow into all the gap behind?

RE: Under plates grout

If you want to be very certain that you're going to get good filling, use a more specialised grout; Sika 300 is a good example. It is rated down to a 3mm gap as being non-shrink and non-metallic.

With long trench like this I would expect some cracking, but not lots... It is non-shrink after all!

A few more questions are raised by your photo:

- Where is this? (Nice shoes, by the way)
- What cause this gap? What was the original detail?
- How readily are the "rarer" Sika products available where you are?

RE: Under plates grout

(OP)

We don't have Sika 300.. only Sika 215 which still has 10mm minimize gap. I'm in Indonesia.

The gap is done on purpose by the accent installer so water won't be stuck if there is no gap since there is bound to be micro gap where water can stay or hide by some kind of capillary action and stay. He said if the gap is bigger, the water can drain easily by gravity. See attached picture of the entire accent taken from above. It's only bolded at the top so it's like hanging. That is why I need to put grout in the bottom to make the concrete take the load. Won't epoxy injection after sealing with putty be a better option and letting the bars in the gap stay? Or better to remove the bars before putting the sika 212 non-shrink group?

RE: Under plates grout

Bars with epoxy sounds like something a little "different" and you may be walking a fine line as to the applicability of this...

Ask the local Sika rep for advice if you aren't confident in all the people saying grout here. Also by involving Sika's local rep, they cannot claim you used a product incorrectly.

Well, of course they can, and will... It just is much less likely to stick.

RE: Under plates grout

That's 1600 or so pounds hanging on those screws.

RE: Under plates grout

(OP)

This is the inside top details. The whole width of the accent is 2.3 meters wide by 3 meters height. The screws have 2" expansion bolts both in the inside top and outside (previous picture). They said it can carry the accent. But I want the accent to be carried at bottom too.

Can 10mm non-shrink grout be able to carry load? I was thinking of epoxy as it can fill all the gap, but at very small strain it can only carry light load... so I prefer non-shrink grout since the stress-strain are better.

Also to be sure the bottom can carry the load. I think I'll insert metal sheet to the 10mm bars shim.

RE: Under plates grout

Quote (Chster6)


Can 10mm non-shrink grout be able to carry load? I was thinking of epoxy as it can fill all the gap, but at very small strain it can only carry light load... so I prefer non-shrink grout since the stress-strain are better.

If you went with a low-viscosity epoxy resin (not saying this is the best way to go in this application) for a thickness of 10mm you would be best to pre-place small aggregate (less than 10mm), them thoroughly seal (caulk) up all the edges, and gravity feed the resin. The aggregate will act as a heat sink to avoid thermo cracking of thickened/large mass resin.

Unless you fully seal up the edges/boundaries of the extent of grouting, you will get major leaking and a big mess to clean up! Speaking from experience smile

RE: Under plates grout

I have to agree with the accent installer; if you fill the gap with anything that does not also hermetically seal it (and grout won't do that), rainwater will wick into the resulting micro-gap and corrode the flat leg of the angle at the bottom of the accent assembly. The angle will also corrode with the gap present, but perhaps more uniformly, so it may have a longer life.

I cannot correlate the details shown in the three photos; are they all of the exact same object?

Chster6, how did this come to be your problem?

Why do you wish to fill a gap that a presumably experienced professional would prefer to leave open?


Mike Halloran
Pembroke Pines, FL, USA

RE: Under plates grout

(OP)

Yes they are the same object, the 3 pictures are taken of the bottom inside, top inside, and from the roof outside. Just imagine a rectangular accent sized 2.3 meters wide and 3 meters height.

In object like this. The natural thing is to have the concrete support the accent. But the installer wants to leave gap and hang it. I don't think it is stable. I thought the non-shrink grout can seal it. Won't it? If I use low viscosity epoxy (the same they use in sealing cracks) that can seal it and avoid any water seep. What would be the problem of thermo crack in the epoxy since it can still take the load? In a few days. Glass frames will be put over it so I can't access the bottom anymore.

RE: Under plates grout

Many epoxies give off heat while they cure... That can cause other materials to "misbehave" due to localised heating. That's the thermo crack issue in a nutshell.

RE: Under plates grout

(OP)

After discussion with installer, they said grout ok if sealant will be used since the grout part will be higher than the existing concrete and the angle bar is closed, only the end is open which would be sealed.

I purchased one bag of sika 212 from the retail shop. For those who have used this already. How do you know when you have used too much water? Won't it cause spaces in the mix just like water filling up the spaces in concrete between the aggregates and paste making it weak? Doesn't this occur in non-shrink grout? Why?

RE: Under plates grout

Quote (Chster6)


I purchased one bag of sika 212 from the retail shop. For those who have used this already. How do you know when you have used too much water? Won't it cause spaces in the mix just like water filling up the spaces in concrete between the aggregates and paste making it weak? Doesn't this occur in non-shrink grout? Why?

Grab a copy of the technical/ product data sheet for this product or maybe refer to the bag for mixing instructions and water requirements depending on the characteristics you require.

Usually for grouts it will state: "For plastic grout use X liters of water per 20 kg bag" and "For flowable grout use Y liters of water per 20 kg bag". Y will be greater than X. Do NOT use more water than required. Use a mechanical mixer too and mix for the stated duration.

RE: Under plates grout

"How do you know when you have used too much water?"

When you add more than the bag says. If you haven't worked with t before. DO NOT try to do this by eye!

"Won't it cause spaces in the mix just like water filling up the spaces in concrete between the aggregates and paste making it weak?"

Yes and no. Water becomes an integral part of the grout, through the process of hydrolisation. The "magic" of non-shrink is doing this without shrinkage. Really good grouts do this without expanding at any stage as well. Note: While the more water you add, the lower a strength you get, it is not fair to say that it is "weak". Read the specs, stay within the parameters.

"Doesn't this occur in non-shrink grout? Why?"

Sure it does, but raising the w/c ratio is not the end of the world... This isn't flour; so long as the set flowable consistency product's properties meet your needs you're good to go.

And if you want to try and keep water out, try caulking around the base. That may buy you more time, but this is going to rust eventually. Should have been galvanised, in my opinion.

RE: Under plates grout

(OP)

When the non-shrink grout hardened, would it be able to take the load of the accent? or is it just there to fill in spaces?

In the case of baseplates where it is supposed to take loads. How can this occur when the grout just fill in the spaces?

RE: Under plates grout

The grout acts as a block. Check the compressive stress imposed versus the Min safe compressive strength for the consistency of product you're planning to use.

RE: Under plates grout

(OP)
grout acts as block of what?

RE: Under plates grout

(OP)

The 10mm bar shims were removed because it's not in contact with the floor surface. In fact, the angle bar gap is really about 11mm. Windows and frames will be installed over it on Saturday. After I put the grout in the 11mm gap. Would the angle bar on top of it be in contact with it such that the grout will become loading bearing? Because if it does not, the entire windows and frame will be taken by the handing screws above. So how can I make sure the grout in the gap will take the load of it? Does mere filling it do it?

RE: Under plates grout

"Mere filling" under column base plates takes the load, sometimes many hundreds of tonnes. I can't see why it wouldn't carry a decorative frame.

RE: Under plates grout

Sorry in advance about the Zombie, but the younger of my boys was in ICU from late Jan to mid Feb, so I only just remembered to come back to include this info:

I spoke to the local Sika rep about the 212 outside of Canada and inside of Canada minimum gap issue. It turns out that while the mix design is nearly the same, the maximum aggregate size is 8mm in Canada and 3mm basically everywhere else. It has to do with what they can get for a good price and is done to keep the price down on the Sika 212. Given the basic recommendation/rule of thum of S>=3*Max Aggregate, we get 25mm for the Canadian product.

Now we know, and I feel better again about my faith in Sika.

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