CIVIL-TECT™ - What is it, and why?

CHARLES: Hello, and welcome to our latest webinar. The subject for today is CIVIL-TECT and the launch. We really appreciate having you all on board, giving up time to listen to what we've got for you today. My name is Charles Currie, and I'm based in Napier, NZ, part of the supply and civil sales team. With me today presenting is Brendan Stead, our marketing coordinator. Welcome, Brendan.

BRENDAN: Thanks, Charles. Great to be on board. Apologies to everybody who was expecting Doug Hamlin to join us. He has been unable to come along at the last minute, which is unfortunate because he's got a good deal more technical knowledge than I do. But hoping we can make some sense of it all for you.

CHARLES: That's awesome. Thanks, Brendan. At MARKHAM, we're all about adding life to concrete by embracing challenges. So excited to bring you the launch of our new system called CIVIL-TECT: a designed and installed systematized approach for remediating ageing concrete infrastructure, adding durability and service life.

So at the end of the session, we're going to have a Q&A; we're going to have time for questions and answers. So please feel free to add anything to the button at the bottom of your screen as we go along, and we'll cover that off at the end. Also, we're going to do a quick poll to just share about your background so we can tailor it as we go. I'll leave that up for 20 seconds also. Looks good. Okay, mostly structural.

Awesome! So the learning outcomes for today:

• The hidden issues of concrete structural deterioration. So MARKHAM sees real-life examples of this all the time where concrete structures are not reaching their intended service life. So what are the underlying issues for these?
• Also, breaking the maintenance cycle. A lot of asset owners are locked into short-term maintenance cycles, which ultimately are very expensive. So what can we do to break this?
• Also, mainly the CIVIL-TECT. So this is our systematic approach, as we said, to concrete infrastructure remediation.
• And we'll also be covering off our end-to-end performance-based warranties, so key benefits of our approach for everyone involved. So take us away, Brendan.

BRENDAN: Thanks, Charles. So concrete structural deterioration is something that MARKHAM has been working with for a long time. As some of you may know, we've been in the industry for about 25 years now. Personally, I've already been with MARKHAM for about eight of those, learning all the time. One of the key things that we repeatedly emphasise is the need to act early in maintenance. We hear from time to time of concrete structural disasters. I just noticed this morning, there was news of a partial viaduct collapse in northern Spain. Fortunately, as far as I know, there was nobody killed in that, but there have been other more serious incidents. So it does emphasise, I think, the need to be onto your maintenance game.

So what we often cite is this Law of Fives, which is proposed by Wolter Reinhold de Sitter; part-time professor in the design of structures in concrete at Eindhoven University of Technology, for structural concrete maintenance. The point being, you can take a small step at the outcome of the structure's life; or you can take a step that cost you five times as much when you see corrosion initiation processes are underway; and it keeps stepping up as the deterioration cycle goes. But as you reach the point where there's extensive damage, then it's going to cost you 125 times as much as it would have cost if you had taken some preventative measures early. So it's just a little illustration of the old saying, I guess, a stitch in time. But it's something that we do like to point to, the need of acting early.

One of the points about concrete deterioration is how a lot of what's going on and a lot of the deterioration process is unseen. There's internal reactions happening within the concrete itself. Typically, these are driven by moisture. You've got contaminants carried by moisture into the concrete, and the contaminant reactions are also driven by moisture. So you've got things happening inside the concrete, such as Alkali-Silica Reactivity (ASR), or Delayed Ettringite Formation (DEF). Then you have things like carbonation and other things that ultimately lead to the steel corroding, and then you get spalling where the concrete breaks away.

Now, you might have these things going on, and one of your options might be to do nothing. Unfortunately, we see a lot of people take that option of doing nothing, for as long as they can. As we've already pointed out, all that's going to do is drive up the ultimate repair bill very considerably.

Then you get patchwork, which is what we call cosmetics, when you're coating over a problem. Hand in hand with that goes the fact that people are surprised sometimes to realise that patch repairs have generated the need for further repairs. You get a thing called incipient anode formation, where you get new breakouts and spalling right next to what you've just repaired. So we want to emphasise that this is actually happening inside the concrete, and the need to have a holistic view of the structure and a holistic view of what's happening to it so that you have a holistic approach to your maintenance.

What we observe tends to happen is a maintenance cycle where small repairs are done far too frequently, and also, they start being needed very early in what was supposed to be the structure's service life. We have a structure with a 50 or 100-year service life, and you're looking at it in 20 years and it's needing significant maintenance. That shouldn't be happening. So how do we break that cycle is to treat inside the concrete. We have got a lot of material online already about the science behind this, and certainly I'm happy to point anybody to that after the webinar.

Now, we use a hydrogel treatment to actually treat the porosity of the concrete and bind up the moisture that's moving around inside the concrete and carrying contaminants and feeding internal reactions. The hydrogel treatment actually arrests the internal reactions, and it's a means to treating the structure holistically. Having said that, once you're doing maintenance, hydrogel by itself is not necessarily all that these structures are going to need, so it does need to be assessed properly. But we want to make these repairs or these treatments and remediations last longer, and encourage the structure to extend back to what was its intended service life when you've seen deterioration already.

All of that has gone into driving what we've put together in our CIVIL-TECT system. It includes many elements that we've been doing for many years. But typically, it offers two or three-part system for your given structure. It's an infrastructure protection system. It's easy to specify as a single package, rather than having to choose multiple products and then wondering if they're compatible with each other. We've arranged it so that the system comes in a number of variants. So depending on your structure and its needs and its age, we can select the variant that suits it, which is an economical approach. It can be very customised, if need be, and on the other hand, it can be very simple to specify. Does that make it clear, Charles?

CHARLES: Yes, that's awesome. Thanks very much.

BRENDAN: You take us away on what we mentioned earlier about the end-to-end service?

CHARLES: Yes. So the end-to-end service, we can assist with design and specification, estimating, supply and application, and quality control. Also, I particularly want to mention our performance-based warranty. This is because we've obviously been involved in the whole process and we're not just replacing defective products, as you might say. It is of course project-specific and tied to the outcomes that the client is wanting to see.

BRENDAN: Yes, that's good. Performance-based, and project-specific are important points.

CHARLES: So there are many uses for this, of course. Bridges; culverts; wharfs and other marine areas; multi-level carparks; dams and tanks, including potable water and sewage.

That brings us to the Q&A session, I'll see if there's anything in the box.

BRENDAN: Take that there. But I'll actually include Doug's email in the follow-up email that we send out to everybody. You can get in touch with us if you've got specific project inquiries, happy to look at those.

CHARLES: Awesome. There's one just asking about the warranty, which is a good one for this one; the length of time?

BRENDAN: How long is the warranty? The warranty varies. As we've said, it's project-specific and it's performance-based. So we like to assess the condition of the structure and we like to work towards what the structure's intended design life is. We used to say typically 15 years. In the case of concrete infrastructure, typically now, we would try and issue, wherever possible, a much longer warranty than that. 25 years as a minimum, and we have issued longer periods. Important to understand at all times that it does depend on the condition of the structure when we first look at it.

CHARLES: Yes, that's awesome. Also, how often does it need to be reapplied?

BRENDAN: Okay. So strictly speaking, the hydrogel treatment itself never has to be reapplied. If we are using the CONQOR SC2, which is a topical treatment alongside the hydrogel treatment, which will be required in some cases, that does have a reapplication period. I think it's in the vicinity of about 10 years, but I'll have to double-check on that detail. There again, it’s project-specific, depending on wear and tear.

CHARLES: Exactly. Yes, that's good. Also, one last one. Can I use this on top of patch repairs? Good question.

BRENDAN: Yes, absolutely. You can use it on top of patch repairs. But it plays into what I mentioned earlier about repairs generating repairs. It's all too often that patching will trigger forcing the reaction into the concrete beside where the patch has been done – incipient anode formation – and then you get breakouts beside new repairs. So yes, we do encourage the CIVIL-TECT system to be used in conjunction with patch repairs, if at all possible. There's a couple of different ways to do it. Depending on the condition of concrete, you can treat the concrete with hydrogel before you put the patch in. That is a question which I really rather wish that Doug was here to answer, because it's a bit of a technical one! If anybody's got a project-specific question on that, be free to send us an email.

CHARLES: Awesome. Actually, this is properly the last one now! Are you able to use the system for new structures, too?

BRENDAN: Yes, there is a variant for new structures. If you're talking new structures, we'd like to introduce the discussion of admixtures for the concrete itself, for waterproofing and durability. We also have some specialised admixtures which are ideal for marine situations, for instance, the CONQOR B52. So yes, we do definitely have treatments for new civil infrastructure to make it durable from day dot. Also, just while we're mentioning the civil infrastructure, things like precast and load cover remediation, there's ways that we've been involved in that space for quite some time.

CHARLES: Right. Is there anything else you wanted to add, Brendan?

BRENDAN: No, I think that's fairly good. Another question popped in there, Charles. How do you remediate low cover? I can send you some detailed information on this. But with the hydrogel treatment, the spray-applied AQURON 2000 or AQURON 7000 specifically, because they close up the porosity and waterproof the concrete and prevent the movement of water into the concrete, they can double the effective cover of the concrete over the reinforcing steel. We've had situations where we've been able to save quite expensive precast elements. Some of those bridge beams and so forth can be massive and quite large, and the steel may have moved when the concrete has been poured, and you get a non-conformance. It's very embarrassing for everybody involved, and we've actually rescued those situations a number of times. But that's how it's done, is by increasing the density and the waterproof value of the concrete over the reinforcing steel. As I said, we do have a study paper on it if anybody's interested in the science.

CHARLES: Yes, that's awesome. Well, thanks very much for covering that off for us, Brendan. As you say, if there's any inquiries, feel free to send them through to Doug, Brendan, or myself, and we'll be in touch. But thanks very much for your time, and we'll look forward to seeing you next time.

BRENDAN: Thanks, everybody. Good to have you on board. We'll send out follow-up emails, and there'll be recording available. Thank you.