The Future Of Sustainable Concrete

In this episode, Ivan Diaz Loya, Vice President of Technical Services at Ozinga, joins host Dave Walsh to discuss why people should care about reducing carbon in the manufacture of concrete, the standards helping the industry move forward, and what the future for sustainable concrete holds in store. Then, JP Ervin discusses pioneering standards work on the otherworldly phenomenon of karst, including caves, underground streams, and sinkholes.

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Transcript

Voiceover (00:06):

Standards are everywhere from the floor beneath your feet, to the aircraft above your head. This is standards impact presented by A STM International.

Dave Walsh (00:21):

Welcome to Standards Impact, the official podcast of A STM International. I'm your host, Dave Walsh, editor in chief of ASTMs flagship publication Standardization News. Today we're joined by Ivan Diaz loa. Ivan is the Vice President of technical services at Ozinga, and he's with us now to discuss standards to reduce carbon and the progress being made to create cleaner concrete. Ivan, thanks for joining us.

Ivan Diaz Loya (00:52):

Thanks for having me, Dave.

Dave Walsh (00:54):

Well, I guess the first thing we should do is probably introduce you to our audience and maybe you could tell us a little bit about your background. Maybe you could tell us how you got involved in the field of concrete specifically, and then maybe what brought you to A STM after that?

Ivan Diaz Loya (01:07):

Yeah, yeah, absolutely. I started out getting an internship over in GCC, which is headquarters in Chihuahua, Mexico, which is where I'm from. That was right after I finished my bachelor's degree in materials engineering, so I got an internship there with the r and d lab and did a lot of work with standards, doing some r and d and different types of alternatives, cements that were working on and new projects and things like that. And then later on I went out to work on my PhD over at Louisiana Tech. The work there was on alternative cements. We tried to adapt standards that were made for the Portland cement industry in concrete and to this new materials, but kind of became clear to me that there was actually a need for developing new standards for these new emergent materials that were coming up. So later on I applied for a scholarship over at C nine, which has the Catherine and Brian Mallard scholarship. I ended up getting that scholarship. I was doing some work on geopolymer concrete, fly based geopolymer concrete, just kind of highlighting the need for new standards for new materials. So that's kind of how I got into it. Now, as you mentioned, I'm with oa, I'm vice president of technical services, and I'm responsible for QC for vetting new technologies and some r and d as well.

Dave Walsh (02:32):

Before we get into the topic of standards development and some other questions that I was going to pose to you, I thought maybe we should start with a very basic one for not just our audience, but the wider audience that this podcast reaches. Why should people care about reducing carbon in the manufacturer of concrete?

Ivan Diaz Loya (02:48):

People should care about reducing CO2 emissions in general. Actually, concrete has a fairly low embodied CO2 compared to other materials on a per ton basis. There's just a lot of it produced out there. You might have heard the statistic that concrete is the most consumed material next to water in the world. The numbers on concrete production are pretty staggering, and so that makes the emissions kind of be significant. At the same time, the main driver for emissions in concrete is Portland Cement. About 3% CO2 emissions in the US are associated with the production of Portland Cement. So concrete is about 17 to 15% cement by weight depending on the performance requirements for concrete. On average, a cubic meter of concrete has a hundred to 300 kilograms of CO2 of embodied carbon or CO2 per cubic meter of concrete. There's definitely room for improvement there, and I think there's a responsibility from the industry to work on lowering that number.

Dave Walsh (03:57):

I was going to follow up with an earlier comment. You said that sounded interesting because I've heard before that concrete is the second most consumed material on Earth after water. Have you heard any numbers for that? Because I've heard that fact before. Do you know how much cement is created in a year or how much concrete is created in a year?

Ivan Diaz Loya (04:14):

Well, I think the number is about 4.1 billion tons according to the Global Cement and Concrete Association. Pretty big number.

Dave Walsh (04:24):

Yeah, that's a huge number. That's pretty impressive. So you're a member of committee CO nine on concrete and concrete aggregates. So what are some of the things you're working on in your committees and specifically what standards are you involved with? What's going on there?

Ivan Diaz Loya (04:37):

To tie it up to what I was mentioning before, one of the clearest ways to reduce CO2 in concrete is by using supplementary cement tissues materials to replace part of the cement. There's been some big changes in the industry related to the availability of supplementary cementitious materials, if you can, keeping track of the news in terms of energy production, about 50% of the energy in the US used to come from coal fired power plants, and there's been a dramatic change in that regard over the last 12 years. There's been a lot of closures of coal fired power plants. Now we're looking at probably more around just over 30% of power being produced by coal fired power plants. Fly ash, the most whitely used supplementary cementitious material or SEM in concrete has been affected by that less coal firepower production. That means less fly. There's been a lot of work in C nine as you mentioned. I'm a part of that and specifically on C 9 24, which is the subcommittee and supplementary cementitious materials to try to increase the pool of S SCS that we can use in concrete, and that's changes to existing standards, developing new standards. Recently there was a lot of changes that took place in A-S-C-M-C six 18, which is a standard specification for flys and natural S for using concrete to aim at exactly doing that to try to expand the pool of supplementary cementitious materials that we use in concrete.

Dave Walsh (06:13):

Well, you just touched on one of the new technologies, one of the sustainable new technologies in your answer just now that you mentioned fly ash, but some of the other technologies I've heard of are nanotechnology, blended cement. I imagine that these technologies, it takes a lot to keep up with them in the standards world. Technology can get a little ahead of the standards. So how are you keeping up and how are you going to address that?

Ivan Diaz Loya (06:36):

There's definitely many new technologies and emerging materials trying to address lowering body CO2 in concrete. For example, one of these new technologies or new emerging materials comes to mind is ground glass, and I'm talking about post-consumer glass, basically your beer bottles and all kinds of waste glass being taken to a recycled facility, ground to a fine powder, and basically using that as a supplementary cementitious material. So that was one good example of subcommittee C 9 24 developing a standard to allow the user of these materials in concrete. You kind of keep up with them by just staying involved, and it's impossible to be involved with everything, but you can pick your battles in terms of what you think is interesting. What can you think that can be impactful for the industry? There's also a new committee on C one, which I'm also a part of C one, which is a committee on cement.

(07:37):

There's a subcommittee, as I mentioned, C one 13 on special cements, and there's a lot of focus on developing new standards, specifications and test methods for this new emerging materials. A lot of these materials, there's a lot of good materials out there. The hurdle or the obstacle, one of the main obstacles they face is the lack of standards that can give confidence to the buyer or purchaser and give confidence to the producer that they're producing good quality material and basically facilitates the commerce between the two. So those are examples of activities that are going on, and I keep up with them by just maintaining my A STM membership. I try to attend meetings regularly. I think I've just missed a meeting or two in the last 10 years probably. Like I mentioned, you can't be involved with everything, but you got to pick what you can contribute most in within your subcommittees and just really trying to dive in into the things that you can be involved with.

Dave Walsh (08:42):

We've discussed several different cementitious materials now, several different types, fly ash. You mentioned ground glass in a powder form. What do you think is the future for sustainable concrete? What do you think the best path is forward? I mean, is it a combination of those materials or is there one that you think is the future?

Ivan Diaz Loya (08:59):

Certainly many options. Portland Cement Association released a roadmap for a carbon neutrality and that roadmap, it's a five prong approach, is related to reducing clinker amount cement, cement itself, concrete construction and carbonation, and so without going into depth to every one of 'em, but I think the ones that are more promising are definitely an increased use of supplementary cementitious materials. They're great for the concrete industry because not only they reduce the embodied CO2 in concrete, you have materials like fly ash. Also, you have a wide availability of slack cement, which is a byproduct of the steel making industry. Those are great ways to directly reduce the amount of CO2 in concrete. The work for doing that is already being laid out. As I mentioned, there's a ommunity specialist cements that is working on trying to facilitate the commerce of this type of materials. We're working on revising new standards. As I mentioned, A-S-T-M-C six 18 did a big revision in allowing certain materials that weren't allowed before, such as ground bottom ash. That's the bottom ash that comes from the combustion of coal as well. I think the groundwork is being laid out right now. It's a long process, but I think A STM right now is working towards revising their standards, developing new standards, and making sure that those are reflective of what's going on out there in the marketplace, making sure that we have sound technical background behind those standards.

Dave Walsh (10:43):

As a layperson, I think one of the most interesting aspects of concrete that we've been discussing is the nanotechnology, and I've read about nano silica and how this makes concrete denser and harder and more durable. Is that a realistic way to go in the future, or is it cost prohibitive or is it kind of a ways off it? It just sounds very interesting to me.

Ivan Diaz Loya (11:05):

Yeah, that's right, Dave. There's definitely a lot of interest in nanotechnology. C 9 24 right now is currently working on developing a new standard specification for the use of colloidal silica and concrete. So colloidal silica is basically another word for nano silica. It's a very small nano size silica, a more silica particles that are come to suspension and are basically kind of doses in that mixture in concrete. There's a lot of research studies that they say they can provide a benefit in concrete, similar to other supplementary cementitious materials, how promising that is or how much of the gap that we have can fill in. I think that remains to be seen, but I think there's definitely a need for a standard for colloidal silica and other nano technologies that may facilitate the commerce of these type of new technologies.

Dave Walsh (11:59):

You work for ozinga, which is a pretty big cement company. Maybe you could tell us about what you do in your daily work. How do you help reduce carbon emissions day to day? How do standards play into that?

Ivan Diaz Loya (12:11):

Yeah, so I work for ozinga. As you mentioned. Ozinga is a family owned company, fourth generation, privately owned company that has a strong sense of responsibility to lower body CO2 in concrete. With that, we are working constantly and try to develop new technologies, new materials that can help us achieve that goal. We always have to keep in mind what are the gars that we have in terms of the standard specifications where we can fit in to be able to introduce these new materials on a daily basis. I just make sure that we're sourcing sustainable and high quality cementitious materials. I enjoy developing partnerships with universities that can lead to the production of more sustainable concrete and just working with people with new ideas and technologies, talking with startups, vetting new technologies. That's something that I enjoy and I do on a daily basis.

Dave Walsh (13:12):

What is something about your work or maybe the cement industry in general that might surprise listeners? What's something that we would not have guessed?

Ivan Diaz Loya (13:20):

Well, I think one of the things that people would be surprised about is how much work gets put into standards, how often revisions happens in standard specifications and test methods and guides. There's a lot of background work that goes into it and try to make changes to standards that reflect the latest information and latest research that we have and make sure that our standards are up to date with that, that they're also up to date in terms of changes in the industry. As I mentioned, the change in the fly industry, so there's a lot of change that goes into it, and I think a lot of people may see standards as being much more unflexible than they are.

Dave Walsh (14:06):

How much cleaner and how much more sustainable do you think the cement industry can become? Do you think there's a lot of room for reducing carbon? Do you think you're almost at the limit? How much more do you think can be done?

Ivan Diaz Loya (14:17):

There's definitely room. I think there's some aspects that have more room than others. I think that we should be working on all aspects to be able to reduce. I think that, for example, optimizing processes and so forth, instrument managed production also go a long way, but you can only optimize so much, although you can constantly be optimizing, but I think there's some aspects that have more potential to be impactful than others. As I mentioned, I think the use of supplementary cementitious materials is a big one. I think that alternative cements definitely have a lot of potential in helping us lower or making bigger strides in lowering the body CO2 in concrete, and I think on my part, I'm happy to say that try to do my part. The company I work for tries to do its part, and that's something that I really enjoy. Well,

Dave Walsh (15:12):

Before we wrap up today, I do have to ask you, I've been asking other podcast speakers the same question, and that is, do you have a favorite standard or is there one that stands out to you? Maybe you think it's cool or it's useful for whatever reason. What is your favorite standard?

Ivan Diaz Loya (15:28):

Yeah, I think that's an easy one. I really do have a soft spot for A-S-T-M-C six 18, which is a standard specification for fly and natural S for using concrete. That's a specification that I've been working on pretty hard over the last five years and making those changes to make sure that they're reflective of the changes that are happening in the industry, and I'm proud to say that I was a contributor to that change and making sure that our standards are up to date and reflective of what's happening in the industry and have the rights guardrails to allow the safe use of new materials

Dave Walsh (16:06):

Separately. I was going to say, does that the standard contribute to sustainability, or is it just very useful for the industry?

Ivan Diaz Loya (16:12):

Definitely contributes to sustainability because it allows us to use a wider pool of supplementary cementitious materials. As I mentioned before with this changes in availability of supplementary cementitious materials for using concrete, the availability of fly edge went from 70 million tons a year back in 2010, 2012 to less than 30. So the use of fly edge, for example, in concrete has remained about constant, just over 10 million tons, but demand for concrete has continued to increase. So fly edge, for example, hasn't been able to keep up with that growth in demand. We need to increase the pool of sems that we use in concrete because SCS are definitely one of the best ways to reduce embodied CO2 in concrete. And not only that, but supplementary cementitious materials also help us make concrete more durable. They have a functional benefit in concrete and make concrete better so it's not just a sustainability part, but actually make concrete last longer. So I think that's definitely key.

Dave Walsh (17:28):

What's the final word for our audience? What would you like to leave them with? Final sort of answer here? I

Ivan Diaz Loya (17:33):

Would invite everybody to get involved with A STM. It's a greater organization to be a part of me as a professional. I've learned a lot of things in A SDM, so particularly to the younger folks, I would definitely encourage them to get involved in A STM. A lot of things that you can take away in your professional life, a lot of mentors that have come across along the way, so it's just a great organization to be a part of.

Dave Walsh (18:00):

Ivan, thanks for being with us today. We really appreciate your time.

Ivan Diaz Loya (18:03):

Thanks for having me, Dave.

Dave Walsh (18:09):

And now it's time for our regular standard spotlight segment with Sen's content editor JP Irvin.

JP Ervin (18:21):

Many people are fascinated by caves. They enchant the imagination and leave us in awe of our natural world, moving us with their beauty, wonder and mystery. Despite the popularity of cave exploration and tourism, many may not be familiar with the word karst, a term for special types of landscape, including caves, underground streams, and sinkhole. Karst is formed by the dissolution of soluble rocks such as limestone. It covers about 20% of the world's land surface spread across Mexico, Slovenia, Ireland, and other important sites in the us. Cars. Topography is part of the springs of Florida, the Carlsbad Caverns in New Mexico and the mammoth cave in Kentucky globally. It is especially prominent in the huge Nullabor plane of Australia and the South China cast, which was designated a world heritage site. In addition to its beauty, cast is important to humans for several reasons. Casts is the soul or primary water supply for 700 million people across the globe, including residents of Rome, Vienna, and San Antonio.

(19:23):

It also creates a unique ecosystem that hosts special organisms, including some found nowhere else but in caves. Kars is also important for agriculture, industry, medicine, paleo, climactic, research and archeology. This phenomenon additionally warrants attention because of safety concerns. Kars susceptible to damage or contamination, and car sinkhole are particularly significant since they threaten human lives and can risk damage to roads, homes, fields, and workplaces. A STM has taken an interest in cars for several years, but in 2019, A STM, soil and Rock Committee D 18 saw the importance of establishing a new subcommittee dedicated to the topic. Since their first meeting in 2020, the subcommittee has been at work developing several standards. One of its most elementary tasks is formalizing terminology and identifying methods to characterize tasks that are crucial for allowing us to understand and discuss the topic. The committee is also considering preliminary environmental impact assessments and methods for mapping groundwater movement in the future. They have an interest in developing methods of monitoring sinkholes and responding to the biological and cultural value of caves. Ultimately, parse is a crucial part of our society and or natural world warranting greater understanding of its importance and preservation of its beauty and its functions.

Dave Walsh (20:45):

If you want to learn more about any of the standards discussed in this episode, visit astm.org for all the latest. And if you enjoyed the show today, remember to like and subscribe so you never miss another episode. I'm Dave Walsh, and this has been Standards Impact presented by A STM International.