This article is an excerpt from Episode 14 of Alchemy-Spetec's podcast The Injection Connection, featuring veteran coatings expert Murray Heywood. (If you'd rather view or listen, an audio/visual version of this excerpt is posted at the bottom of the article.)
Charlie Lerman: One of the things I say and again - and I’ll bounce this off you since you're from the coating side - I always contrast our grouts to coatings because with coatings, you can see them, you can touch them, you can do all kinds of tests. And I also always say it behooves us to train our contractors well and support them to get the products installed correctly because it's not like a coating. When you're a coating manufacturer, if there's a problem with your coating, you come out there, you do a pull test, you do a spark test, you can check the millage of it, you can say the surface prep was wrong and you could say, "You know what, you didn't follow the right installation procedures." With grouting, I’d come out and say the same thing that the contractor didn't follow the correct procedures, but what are we going to do? Cut the wall out? Dig up the whole thing in downtown and show? We can't prove any of that. It's very important. Grouting gets a black eye when it's not installed right because we can't test all those things. And I think that's one of the reasons that grouting has always stayed kind of small is because there are no really great, quantifiable, repeatable engineering tests that work everywhere to test grouting.
Murray Heywood: No, it really comes down to, did the water stop, right?
Charlie: Yes.
Murray: And if the water doesn't stop, that doesn't necessarily mean that there was something wrong with the grout. It's often that the problem was bigger than you thought because you can't see it. You're doing educated guesses. As a grout geek you know, "Well, I’ve seen this before. I know that we're going to have to put a port here and we're going to chase it around here." You can make some educated guesses but you're right. I can go in with the coating and with my gauges and test the DFT and quickly say, "Well, your spec said you're supposed to have 40 mils on here. You've got 20. So you're half of what you should be. Shame on you." Or I can pull the coating off and say, "Well, you have no surface profile, you didn't prepare it." And I’m sure the skeptics are thinking, "Oh, yeah, well, you're just saying that to cover your own butt." It’s virtually unprovable other than, when the water didn't stop it's obviously not working. And they say, "Well, your grout’s no good." I do a lot of failure analysis and failure investigations. That's the majority of what I do now is failure analysis. And I like that, it's kind of like CSI Paint. And I enjoy that. But still to this day, 100 years into this coating thing, the biggest cause of failure is poor application, poor surface preparation, and poor environmental conditions during the application. It always relates, 98% of the time, back to something that didn't go right with the application. And that can be the same with grouting. If you don't know how the water's flowing or if you can't make some educated guesses on how the water's getting in, you don't know where to start. And sometimes, as you know, you could be pumping grout in one side and it's coming out the other side and not doing anything.
Charlie: It always goes somewhere. It's about how we get it to go where we want it to through a foot of concrete. How do we control a liquid? That's what it comes down to.
View the video version of this excerpt...