Bro-Cure 1

[PEinVA]

A contractor specified BroCure as a curing compound on a new building, for the parking garage slabs. We are putting a penetrating sealer on the concrete, any reason this product would cause issues with the sealer?

It is a chemically reactive, silicate based, concrete curing, hardening and sealing compound.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[concretemasonry]

Read the manufactures information.

You curing compound is a relatively short life coating. Sealers are require penetration and some sicone/silicate compounds can be difficult to penetrate until they have aged.

You atempting to apply a pentrating sealer over another sealing compound.

The manufacturers documents should tell you about compatibility with other coatings.

Dick

 

[cvg]

the contractor is guaranteeing the work, so shouldn't he be responsible for making sure it works? Otherwise, make him use the originally specified products for curing and then for sealing. I noticed that you say the contractor is specifying this, why isn't the engineer doing the specifying?

 

[PEinVA]

Sorry, I should have stated the contractor submitted the substitute to use this in place of the specified products.

What good is it if the product doesn't work but the contractor blames us for not saying otherwise. It's easier to the leg work here, then have to fight with them that it was his responsibility.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[cvg]

if you allow the substitute than you should be blamed. just say no

 

[hokie66]

RC,

I looked up the manufacturer's literature, and it is unconvincing. There is no data as to how good a job of curing it does. Maybe things have changed, but in my experience, any curing compound (chlorinated rubber, wax emulsion) which does a good job of curing is likely to interfere with subsequent sealers or finishes. I think you need documentation of actual experience of what is proposed before allowing the contractor to proceed.

 

[Ron]

RCraine...if it is a silicate based reactive "curing" compound it won't go away like the "wax" based dissipating curing compounds you might be used to. The way the silicate based products work is to react with the calcium in the cement near the surface of the concrete and fill the voids with calcium silicate upon reaction. This densifies the surface and "seals" it to some degree.

This is not compatible with a penetrating sealer as the penetrating sealer won't penetrate!

Use one or the other, but don't use both.

 

[PEinVA]

Ron,
Star for you.

Do you have some documents that you read that provide that information. It would be good to have to show the contractor so he knows we're not just being jerks about it.

Thanks.

RCraine

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[Ron]

ACI 302.1 Guide for Concrete Floor and Slab Construction provides some information on silicates and fluosilicates...here is a pertinent section:

"5.7—Liquid surface treatments
Some floor slabs, improperly constructed, can have relatively pervious and soft surfaces that wear or dust rapidly. Though the life of such surfaces can be short, it can be extended by using surface treatments containing certain chemicals,including sodium silicate and the fluosilicates of magnesium and zinc. When these compounds penetrate the floor surface, they react chemically with calcium hydroxide (a product of cement hydration) to form a hard, glassy substance within the pores of the concrete, thereby reducing dusting of the floor and creating a denser, harder surface.

Liquid surface treatments should be considered only as
emergency measures for treatment of deficiencies. They
are not intended to provide additional wear resistance in
new, well-designed, well-constructed and cured floors, nor
to permit the use of lower quality concrete. The most effective use of liquid surface treatments is on existing floors. New floors should be of sufficiently good quality that such treatments are not required.
If for any reason these surface treatments are to be applied
to new concrete floors, the floor should be moist cured. Liquid membrane-forming curing compounds should not be
used because they prevent penetration of the liquid treatment. These surface treatments should be applied only to concrete floors that are at least 28 days old, and that have been thoroughly moist cured and allowed to air dry."

Excerpt from ACI 302.1, section 5.7

 

[PEinVA]

Ron,
I actually found that section yesterday. Thanks again!

RCraine

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke