In the world of concrete, it feels like everything is about sustainability. Yet, one of the more surprising findings from a recent deep dive into the 2023 performance data from the American Concrete Institute’s main SmartBrief newsletter was that none of the top 20-clicked stories in ACI SmartBrief this year were explicitly about sustainability. Industry stakeholders and SmartBrief readers also showed deep interest in 3D printing, structural investigations of major building collapses, and much more intricate R&D, but sustainability was not the hot topic we thought it would be.
But while sustainability might not be the biggest concrete news darling, it is unquestionably at the center of everything happening in the actual industry itself. And that’s not lost on ACI President Antonio Nanni. Just last week, Nanni was at the COP28 conference to offer a peek at what is said to be the world’s first code for low-carbon concrete. SmartBrief recently caught up with Nanni to learn more about the code, the increasing role of fiber-reinforced polymer in the industry, and ACI’s latest center of excellence, PRO.
The following Q&A has been edited for length, clarity and timeliness.
SmartBrief: How would you say, both from from an industry and an academic R&D perspective, concrete sustainability took a step forward in 2023?
Nanni: I would say that sustainability for our industry is a challenge, but also an incredible opportunity. I think what happened in 2023 is the realization in our industry that the sustainability train has left the station, and everybody is on the train. I think what is happening today in terms of the R&D, thanks to the commitment of cement and concrete manufacturers, would have would have been unthinkable a decade ago. Every day, there is something related to a new startup that is looking at carbon capture, new supplemental cementitious materials, or 3D printing. So there is an excitement, and an influx of ideas and creativity, that I think is transforming our industry.
SmartBrief: What is the biggest challenge facing concrete sustainability?
Nanni: The challenge is twofold. The first one is scaling up to meet demand. The issue is not money, because if you can scale up, that means you can address demand from an economic standpoint. But the other challenge is durability.
SmartBrief: What message is ACI trying to send with the publication of it’s low-carbon concrete code?
Nanni: We get it. We’re on top of it. We just don’t talk the talk. We walk the walk. We are coming up with a document that will allow our industry to have references because designers need standards and contractors need specifications. You cannot build without those tools. We do not take safety for granted. Safety remains paramount in what we generate. But I think that there is a higher sensitivity to the issue of sustainability, to the issue of life cycle, to the issue of durability. So we want to build for the future, not for the present.
SmartBrief: What more can you share about the low-carbon concrete code?
Nanni: This low-carbon concrete code is the first step of what I would define as a living document. It is going to change over time. You cannot speak about low-carbon concrete as a recipe that would be good for every country and every region. The way emerging countries develop concrete is different than how it is in the United States, so we cannot have the same recipe. So this first document only addresses the issue of compressive strength as a criterion for low-carbon concrete. But the next step, and perhaps even more importantly, would be to look at the durability of that material system. But it’s work in progress, and all the credit goes to ACI Committee 323, which has done an incredible job to develop this document, really, in one year, which is unheard of in our organization and in many other organizations. So this, again, speaks to the understanding of the importance of this and the dedication of our volunteers and staff to make this a reality.
SmartBrief: Is fiber-reinforced polymer (FRP) a part of this sustainability equation? Is that addressed in the low carbon code? Or is that something that with its own separate advocacy through NEx: An ACI Center of Excellence for Nonmetallic Building Materials?
Nanni: The use of composite reinforcement is primarily to address the issue of corrosion of steel or reinforcement. I don’t think that composites will replace steel completely; just the opposite. FRP will be another tool in the toolbox to address the life cycle of our structures. So when you have issues related to durability, FRP could be the right answer.
SmartBrief: What kind of industry traction is ACI seeing for FRP?
Nanni: Well, the good thing is that the industry is scaling up the price of glass FRP. It is now very competitive, and there is an abundance of these materials. There is a new code, ACI 440.11-22, that was issued a little over a year ago, and it will be included in International Building Code by reference. So we feel that we’re making progress, but that code itself is also in the first iteration. For example, we are not explicitly addressing structures in seismic zones. We don’t specifically address fire protection. But look at our flagship 318 code. It has been around for 100 years, and started as 13 pages in the first edition. Now it’s a little over 600. As we develop new knowledge, we translate that knowledge in specifications and standards that our people use them. I think there is a lot of excitement in the FRP arena. We recently went as a delegation of ACI to Saudi Arabia and held a workshop related to the use of these materials. Saudi Arabia is very interested. For countries that don’t have the access to certain metals, FRP becomes attractive from a resource perspective.
SmartBrief: One last question. ACI has been very central to the civil engineering and structural engineering communities. But lately, through the development of PRO: An ACI Center of Excellence for Advancing Productivity, more of a focus on concrete contractors. Can you speak a little bit to the importance of ACI engaging that community?
Nanni: PRO is really speaking to the fact that, in order to build well, not only do you need good engineering, but you need good contracting, and the two communities have to talk together. Sometimes you see a design that does not account for the fact that somebody has to build it. I dedicated my recent ACI President’s Memo to the meaning of constructability. Because even if I’m an academician, I understand that, you know, there are people really who do it. You know, the guys with the hard hats. The rest of us take credit for many things, but the people in the field are the ones who make the difference.
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