Good afternoon. Welcome to PCI's webinar series. Today's presentation is Understanding Portland Limestone Cement's Role in Precast Pre-Stressed Applications for a Lower Footprint. This webinar is in partnership with Lehigh Hanson. My name is Royce Covington, Manager of Member Services at PCI, and I'll be your moderator for this session. Before I turn the controls over to our presenter today, I have a few introductory items to note. Earlier today, we sent a reminder email to all registered attendees that included a handout of today's presentation. That handout for this webinar can also be found in the handout section of your webinar pane. If you cannot download the handout, please email PCI Marketing at marketing at pci.org as shown on your screen. Note that all attendee lines are muted. The GoToWebinar Toolbox has an area for you to raise your hand. If you raise your hand, you will receive a private chat message from me. If you have a question regarding the material, please type it into the questions pane, where I'll be keeping track of them to read during the Q&A period. Also, a pop-up survey will appear after the webinar ends. Today's presentation will be recorded and uploaded to the PCI eLearning Center. Questions related to specific products or publications will be addressed at the end of the presentation. PCI is a registered provider of AIA-CES, but today's presentation does not contain content that has been endorsed by AIA. Today's presentation is non-CEU. Our presenters for today are Claire Noacel, Technical Service Engineer for Lehigh Cement, servicing the area of New England and New York State. She is a member of ACI Committees 225, 306, and 710. She received her BS in Material and Science and Engineering from Qingdao University of Technology in China, and her MS and PhD in Civil Engineering from University of Missouri in Kansas City. Her research interests includes SEMs and low embodied carbon cementitious system. Joining Claire is Jay Witt, Technical Service Engineer for Lehigh Cement in the Midwest region, including Ohio and Indiana. He has been in the cement and concrete industry since 2000, specializing in providing product technical support to customers while managing innovative portfolios, including research, lab testing, and customer implementation. He is active in ACI national committees on hydraulic cement, slag cement, and mass concrete. Jay earned a BS and MS in Civil Engineering from University of Akron, where he co-opted with the Ohio DOT construction in District 4, completed research in slag cement, and raced concrete canoes. I'll now hand the controls over so that we can begin our presentation. Okay. Thank you, Royce. Are we seeing the presentation? Hearing me okay? We are, but we're only seeing the ... we're not seeing ... there we go. Perfect. Thank you. Okay. Good afternoon. Thank you guys for joining us. Jay and I are super excited to take you guys on a journey to understand Portland limestone cement's role in pre-chasm, pre-stress application for lowering our carbon footprint. So during the next hour, I will briefly discuss the motivation for pushing this type of cement changes. Then Jay will go into the details to discuss the technical advantage of PLC and what and how PLC will impact your daily production. So hopefully by the hour end, the producers in the audience will find your own opportunities to be ahead of this sustainability movement and provide a lower carbon structural product to your customer as well. Next slide. Sorry, Claire, it's not advancing. You may have to click on the actual slide and then hit the forward arrow. Okay. How's that? Still not moving. Can you escape out of the presentation and go back into it? I just did that. Okay. Still not moving. So I can ... oh, there we go. Perfect. Oh, okay. Thank you. Sorry for the delay. Go ahead, Claire. All right. We like suspension. So here is how this webinar is going to flow like this. We'll start with the motivation. We saw more low embodied carbon demand, particular from the procurement sector from all type of owners. So then we'll dive right into PLC intro and how it's impacting your daily production. And we'll discuss some of other innovative strategy available to you to be more sustainable. And last but not least, just a reminder, our road to carbon neutrality for construction and building material is a journey and not a sprint. So we have to take all the tools available to us. And most importantly, we have to be vocal about our concrete product advantages. Because if we don't, other will. I lost the slide. Jay, we can no longer see the presentation. Oh, my. I don't know. Apologize, Claire. Sorry. It may work a little bit better if you turn off your camera for the time being. Yes. I'll do that right now. Okay. How are we doing now? We're still seeing you and not the presentation. All right. Okay. There we go. Okay. There we go. All right. So we talk about the overview. So to start with the sustainability evolution in the building sector, we have to start with LEED certification. And since it starts in the early 2000s, LEED has been really successful reducing the operational carbon emission. So a success story I like to quote for U.S. building sector, our operational energy consumption have not increased since 2005, even though we've added over 50 billion square foot to our building stock. And those operational carbon continue to decline are down 30 percent from 05 level. Now I've introduced you twice about the concept of operational carbon, OC. So what is this? Operational carbon is energy consumption right after commission and throughout service life for a building. So since Paris Agreement and the climate change movement taking momentum, the other part of carbon, which is embodied carbon, is being paid increasing amount of attention. So EC is short for embodied carbon. Now what it is, is upstream product manufacturing, transport, transportation of the construct material. So with a combination of EC and OC, we really complete a life cycle analysis of a building. So how we measure the embodied carbon is using something called environmental product declaration. So it's a handful, it's short for EPDs. It's often being compared to a nutritional label. So instead of calories, we're accounting for environmental impact indicator, such as global warming potential, GWP for short. Advancing the slide. So for cement, it's kilogram CO2 per ton of cement. For ready-mix concrete, it's kilogram CO2 per cubic meter of a ready-mix concrete. So for you guys, precast, pre-stressed is kilogram CO2 per ton of structural product. Next slide. So the trend we're seeing is embodied carbon policy are sweeping through the country like a storm. Right? Carbon Leadership Forum is a non-profit and a material agnostic organization. So they really have been providing tools for different level of jurisdiction on developing their own low embodied carbon policies. So here is a map of current policy ranging from local to state or provincial to a bigger, like a federal and national level. So many of these policies you see can be summarized with two pillars approach. So first, we see increasing the number of EPDs, so we can learn from the data and improve the data quality of the source information. And second, among those policies, they really want to focus on increasing the availability of low embodied carbon source ingredients and improving manufacturing process. So we can't measure something we don't know. So first, the policy wants to know where the GWP is and therefore can develop a strategy and benchmark for reducing it. Just to put into a spectrum of how these policies have been developing, it's only been almost five years. The first Bi-Clean California Act originally signed into law in October 2017. So not even five years. And this trend has been spread throughout the country. You see heavily throughout the coast region and slowly Midwest states such as Colorado and Minnesota are starting to implement as well. And we don't see this going away. Just to share some current Bi-Clean procurement policy at different level, here is an example of the city of Portland, Oregon. You will see maximum global warming potential per cubic meter of ready mix at each strength class. I know it's very busy, but just get a trend of this. So jumping across to East Coast, Port Authority of New York and New Jersey have similar carbon limits spelled out in a similar fashion. Again, on a bigger level, on federal level, General Services Administration has proposed a GWP limit for each strength class and each type of concrete, such as high, early or lightweight. So cement accounts for 80% or more GWP in concrete. And our industry has recognized where we have a big burden and there are also tremendous opportunities. So anything we can do to reduce those GWPs throughout the supply chain would all benefit. And Portland limestone cement is one of the serious solution we will have. And now Jay will tell you anything you need to know about PLC. Thank you, Claire. I'm back. Hopefully got all the bugs worked out on your part of the presentation so I can go smoothly. But thank you for the introduction. This Portland limestone cement had the opportunity to speak on this for a number of years and to write the specifications with this and be part of this process. All right. Jay, we are not hearing your audio. Okay. It keeps saying I'm muted. Okay. How about now? Yes. Okay. Well, let's keep moving here. Portland limestone cement. Thank you, Claire. We'll move forward. So the first question I get and I always like to define is what actually are we talking about? Is it a new cement? Not really. It's actually been used in Europe 40 plus years. We've seen it in Canada for over 20. We've got some projects in the U.S. that were in 2008 and 2010. But the difference that you need to know from a consumer perspective is what specifications does this fall under? We now move from a C150 cement that you're familiar with. That's our standard type 1 or type 2 or type 5s. But to a C595 specification. So the biggest change here is the amount of limestone in each source. We currently, the C150 spec, the one that you're used to, is allowed up to 5 percent addition of limestone. With the new specification of unfalling under 595, we now can go up to 15 percent. The unique thing is that this product is made from the same clinker. And where exactly is it getting from? In the process of a cement plant, we actually are introducing this at the finish mill. So it's the tail end of the project. And that's the only difference that we have there. Some other differences you might see is the product is typically ground finer. And we'll get into some details of why that would happen. But really we're trying to meet equivalent performance. So that's requiring us to sometimes grind that a little bit finer. And then we'll optimize sulfate for a set control. What does it really look like? You can see the biggest difference is particle size distribution. We're noticing that this is, we have a better particle size distribution by adding some smaller fines. Now the smaller fines come from the limestone, which is a little bit less dense as than the clinker. So in the finish mill that's grinding, this is going to make it a little bit finer. Most people will ask about strength. We've got enough strength testing, not just from our research that we've done, but from other research from professors and within the industry. There's many publications that you'll find that will duplicate these results. For compared to a Type 1, the Type 1L is very similar at most, at the ages. What we're looking for is that carbon reduction in emissions. When you're running the EPDs to find your global warning potential, we can, we see up to 10 percent in just this one aspect alone, just changing from Type 1 to Type 1L. So this is really more of an engineered product that we're using. There's enough durability testing already done and completed with many years of research already completed with that. I can point you to several research papers that you might want to look up if you're interested in that. So how well is this accepted? You can see this chart in 2014. We have a lot of yellow on that and not very much green, and the green is actually the acceptance from the DOTs and from other organizations. But then we jump a few more years from this year. You can see most of the map is actually green. So this is happening not just in the DOTs, but also we're seeing in the FAAs, NAMI Corps, and we're seeing within ACI and international specifications. So how does this really perform? We get some of the details here, but you can see it's actually a particle size distribution. I alluded to that a little bit earlier about the grinding part of this. So we find that the limestone powder is actually presenting a more wider range of distribution, and that's actually going to help our product, not hurt our product. So if you get a little bit finer into the chemistries of things, you have the limestone reacting with a C3A particle that is coming from our cement clinker. So that's going to help the porosity of the product. Then lastly, in a sense, it's a scaffolding effect, which just means we're putting smaller particles in there to kind of fill the gaps. So that gap is now being filled with limestone particle rather than putting a paste in there, a hydration paste. So this is the part that I tend to focus in on in my position here. I get out in the field and I'm in the customer, the rarity mix precast industry, and they want to know what the impact is on their daily production. That's where I kind of get a lot excited about and just go, okay, let's see how this works. So what is the impact at the batch plant? And this is kind of more of a hands-on type approach. So I'm going to compare the type 1L to a type 1. So with mixing, there's no changes. There's no changes in your sequence. There's no adding this before or after. In most cases, in every case that we start out and we don't change a thing. We just change what's in the silos so that the customer already has a silo. They already have the space. There's no added parts to be added. It's very simple. It's a switch in a sense. So then they look at me and go, what do we need to change about mix design? Because they're used to changing things with respect to getting different powders. Maybe they get a type 3 or type 1 day-to-day and they have to know what do we need to change. When we start testing, we don't change a thing. It's one-to-one powder replacement. Water demand, we have found to be similar. Now I say similar because I've had the opportunity to test five different plants using 1L with compared to type 1. We have seen some cases where it's about five to eight pounds more water and we've seen some cases where it's five to eight pounds less water. So the answer is yes, unfortunately. So it really is dependent upon the plant that it's coming from, but for the most part, we're going to leave the water demand. What about using slags or fly ash for your SCMs? In our testing and in many other research testing has indicated similar results, if not greater. So for the most part, we're seeing some greater reaction with these products. And admixture adjustment, this is very similar. All these answers are pretty much the same. Your dosage rates should be similar and that's what we're finding. The predominant answer is we're going to add a little bit more air dosage. And what I've found is with your polycarboxylates, which is your high range water reducers, you will find a little bit less. So at the precast plant, the guys are actually working in placing the products. They want to know, how's it finish? What's our set time? Do I need to let it sit there longer? What's my strength gain? Can I pull my forms when I want to? So if you compare the two, we're finding better finishability and that goes back to the particle size distribution. We're finding that we're getting a little bit more time on the set time, which is sometimes beneficial during the summer months, the warmer months. And then the cooler months, that's something you got to consider. A strength gain, we've got enough results that's showing a similar strength gain on the curves. And one of the things we're starting to get into with the precast is your stability. And this is where you get into your SCC, your self-consolidating concretes. How is my stability? How is my flow going to happen? Do I need to add vibration to it? Do I need to place it properly? And my answer to that is, well, let's start in the fundamentals. Now let's start with your mix design and let's move towards that direction. If there's a stability issue, to me, it's primarily done with aggregates. But we're now noticing that you can sometimes have a different instability, but it's close. Normally people love to talk about strengths. To me, that's an important concept of it. How's my strengths? So we've got some lab testing here and you can notice that the precast mixes are typically geared towards 12-hour, 18-hour, 24. They need that strength immediately. In this example, we have at a 0.37 water-cement ratio. We're getting very similar strengths close to where we need to be. In an example of 850 pounds, there's some differential at the 12-hour, but you can see it's 24-hour. We're coming back on board with the Type 1L. So here's an example of our SEMs, a fly ash. You can see there's some very similars, whether you have a Type 1 or a Type 1L, which is on the left-hand side. With slag, about 30% of some of our testing, you can see we're still getting some similar results. This is in-house testing that we have done. It's a, we believe in show me. And so we've read enough research papers to say these same things. We were able to duplicate it in our labs. So what kind of strategy do we need to implement moving forward? Now, you may be in an area that, like the region I'm in, the predominant cement available today is Type 1L. We have very little Type 1 in our market. So that's starting to become more prevalent as more cement plants are turning over and switching to that. But where do you start? What do you do? Do I just switch? These are all really, really good questions. To me, when you're looking at the grand, the overall holistic part of it in what do I do first and how do I reduce my carbon in this particular material? And there's really, unfortunately, there's not one definitive answer. We believe that Type 1L is a very quick and easy answer that is easily done, that you can move forward and get your first initial savings. But as you look at all of, we call them levers, it seems to be the buzzword now, is at the core of me, I start at the mix design. How are we going to optimize our cement and aggregates? And then we talk about when do you actually need this mix? When are you going to use this mixture? What time of the year do we need to make changes there? And I know I'm complicating things and I get a lot of really odd looks when I'm in a precast plant that make me look up and make sure I know where the door is before they throw something at me of suggesting the fact that they change their mixes so often. To me, that's becoming a more efficient and more optimizing with what you're doing for when you're doing it. And lastly, I'm going to touch on blending cements. So when we talk about aggregates, we talk about the efficiency of the aggregates. Now with this picture, you'll easily see from left to right, we're actually decreasing the amount of paste in the mixture. And if you go back as far as Abrams and look at the details of mix, the core of concrete mix design is reducing the amount of paste. It's that paste that inherently creates some durability, not durability, some engineering properties that they really don't want. But we can make the mix better by using a well-graded aggregate. Many people will blend their aggregates and I've come on under talk about, we don't have an extra bin. And I just kind of politely say, you're going to need to get one. You need that kind of control. And what I find that the producers that have more bins, have more control, they have a smaller standard deviation in their mixtures, they have a better mix day to day. So when we optimize an aggregate, if you don't worry about your aggregates, you get a poorly grade material, you get different shapes and sizes. Ultimately, your mix design suffers. Your mix design suffers in needing higher water, which is obviously reduces your strength. And then it requires more paste for that aggregate. When you dive into well-graded aggregate, and I'm not the first one to broadcast this. There's many before me that have created great programs and that will look at your aggregates, figure out what a good optimum is, where you've got a well-graded varied shape, where it's going to reduce our amount of water, better strength, and ultimately, everything is more efficient. And I tend to use that word quite a bit because I think that is our overwhelming push and direction that we need to head. What is our efficiency? So with respect to cement and SCM's, SCM's are commonly being implemented. But when you're not concerned about this aspect, where you have like a poor or outdated design that might've worked 10 years ago, but now we're providing a much better resources figuring out and investigating what each material is doing. The SCM's have come on board for durability aspects and have added great durability for resistance to many aspects. But when you're using old mix designs, we look at, we talk about a term in our world is how many pounds per square inch? How many, it's how much PSI are you getting per pound of cement? And I started evaluating each cement. Now this value is typically between six and eight PSI per pound. But when you're looking at designing a mix, I've gotten as high as 14 when using an SCM in cement. So in that aspect, we're creating more strength with the proper design. We're getting better dispersion, better hydration. And then we're a lot, we can able to adjust based on current conditions, conditions today and conditions in December, where we can go, you know what, maybe we don't need that accelerator during the middle of summer. Maybe we can back off from going from 2% to 1% or eight ounces, 16 ounces. Maybe we can back off these things or maybe we can pour a different mix on our Friday, Saturday mix since we know we're not coming in on a Sunday. Those are some aspects that when you look at design, that's the efficiency that I'm talking about. So I'm going to walk you through a couple other examples from a GWP or from a carbon type footprint aspects. We're now able to identify each of the materials that are in the mixture and give it some value. So for this example, I'm gonna walk through about five different mixes. So the first mix is type three. If you look down here, we have a GWP of 342. And so with the next mixture, we use the type 1L at 100%. You can see we've already reduced that and this is all done through the EDPs and the product category rules. And that's where all this information is coming. So then now, what if we blend? And I'll get into why we're in a blend here in a second, but just go with me here for a second. Type three and type one, a smash 50-50. We're down to 330, kind of in between the two marks. What if we're gonna blend 70-30? Well, we're kind of playing with that GWP, but we're still less than our original type three of ordinary Portland cement. So then we get our last example. Now we're gonna add an SEM. This SEM happens to be slag in there. And then you'll see the aspect, we're down to 259. Greatly decreased that value. And there may be a project that calls out for a GWP max on your material. This is where we're headed. Now, what I like to point out about the last mixture, you can see the strength at 12 hours is slightly hindered at 12 hours. But what we know about an SEM is it catches up fairly quickly, especially with heat. So another option, blending. Hopefully you're not looking at me weird right now, but I can't see anyhow. But blending type three with type 1L. Why on earth would we do this? And hopefully I'll answer that. Why use this option? It is creative, absolutely. But to me, we looked at the prior example, we talked about how sustainable this is, a blending type three and a type one. We talked about cement efficiency. We've got enough testing done in this that we can see the cement efficiency of this blend. Remember, we're doing a particle size distribution and we know that type three is a little bit finer than our standard type one and type 1L. The cement availability is probably the biggest reason why I've been pushing this, because we know that there is some flux with supply and demand. And we also know that a cement plant can produce more type one per hour than it can type three. So you get in tight spots where supply becomes very, very crucial. We can produce more type one. But then the last one, why are you concerned? All those factors you probably may not be concerned, but the last one is economically. The predominant price of type three is going to be higher than a type one. It costs a lot more to produce and there's less of it. So has this been done? Is this just something I'm pulling out of thin air? No, I actually started it back in 2005. We've got some full-scale testing in there. And then we currently have plants right now that are using this option with some history over the past two years. And this option became a demand in this region because we were simply just out of type three at the time. And you can't stop a plant, obviously, but you need options. And this was a great option for them to go in. So some benefits of the option. We talked about the reducing the carbon footprint, the reduction in costs, 100%, the adjustments that can be made. And these adjustments we have seen, and I've proposed this idea, which remember, I'm kind of a mad scientist, I guess. Why don't we just try this? I realized that the plant can, I can't always do that, but we have some plants that have more than one size and they're able to do this. And they can actually control what they're going to use each day based upon how cool or how cold the concrete is, how cool the exterior elements are. In mid-summer, why are you using type three? Then in the fall and the spring, you could use these blends. And then lastly, it'll relieve some supply pressure and it'll help everybody out. Okay, here's some testing, some strengths. What's it look like in strengths? We started with a 500-ton pound, no air, just to kind of see, okay, where are we at? Are we close? And you can see, we're not too far off even in one day. Now, I realize that precast is a whole different animal, and I'll show you some more examples here in a second. But what about our set time? What about our water-cement ratio? We know that type three is finer and it require more water. We definitely saw all of these aspects. And even in the blend was a nice compromise between the initial set. You can see the 50-50 blend had a little bit faster set than what an average middle of the road would have been between the type one and the type three. So what about a precast mix? Now a little bit more cementitious. We need that more cementitious for that early high strength, 700 pounds. You can see between the two, you jump from the type three on your left there and all the way over to the 50-50 blend, all the way over to one 50-50 blend with an accelerator. So the eight hours, the first column there, the 20, the one day is the second column. You can see the accelerated mixes is coming on board quite fast. So this shows you that we can really manipulate, if you may, or really design things to do what we want them to do. We just need to figure these things out. So what does it look like with a type one L? Okay, now we're blending a type three with a type one L. We've got some results here, eight, 12 hour, 24 hour. Obviously between the type three, which is on the left, and then what's the next one over to type one, we see a dip in our eight hour and even our 12 and 24. That is, we know this, but this is in a lab environment. And then, so if you put this into the heat in a warmer environment, your strengths are going to climb up because of that exothermic reaction of the cement and the water. And here is an example of that exothermic reaction. What we do is we measure temperatures and you can see all four cement categories are represented down there. What's interesting is the type three is kind of right there in the middle, you've got the 70, 30 acting a little bit faster. And that is that particle size distribution where you've got a bunch of fines combined with a little bit coarser material. You can see all the way down on the right-hand side that type one is a little bit slower for the heat. And also the heat rise is not quite as high. You can see that it's about 104 degrees. Let's dive in this a little bit further. I've got a couple more slides with some graphs. hopefully you guys can stay with me. You know, the type three. Now we're gonna, we got here, all of the combinations are witnessed here. We got there, type one all the way on the right-hand side, all the way from the type three on the other side. The big difference here in this graph, and I wanted to show you, is there's the four mixes from the mix two through five is with an accelerator. So this is us venturing out going, okay, so you don't have type three, what are we gonna do? How's it gonna respond? What happens to our 10 hours, 16 hours, 22 hours, seven days? You know, let's get a good handle what's going on here. So here is the hydration curves. You can see they're a little bit, they're very close together, and that's one to indicate. Now, obviously the peaks are different, but that upward slope, that is where your set times and your strength gain is happening within that first couple of hours. So your preset time is not gonna change too much. If you are adding heat, or maybe you're adding a blanket, you know, those are some things you have to consider. All right, so now we're done with the highly technical part of it. I'll slow down just a hair, but I wanted to show you one more thing of, you know, we're considering CO2 reduction in this. Let's consider it a real life example, and this particular example is a beam that has 14 yards of concrete in it. We have four different scenarios that we run here. The straight Portland cement, 100%, 50-50, 70-30, and then we've got one with slag in it. What are we actually saving? So this graph's a little bit backwards. It took a little while for me to figure it out, but we're measuring percent reduction. So the higher the quantity, the better. So we've got our first graph is reduction. I said that wrong, I sure did. See, I told you I messed it up. Then you've got next one, it is a 50-50 blend. Now this 50-50 blend is type three with one blend, and the next one is a 70-30. And then this last one, now we have, this is a percent reduction from the original. And then we have a 72, that should be 75, there's a click order, of type one with our slide. So we're able to show you that we're able to reduce the amount of CO2 by this combination in a real-life example. Where's this come into play? Once again, you could have a specification requiring these aspects. I could see that happening sometimes too, depending on what you think. So here's the actual CO2 avoided, and you can see the best case scenario is all the way down there with the SCMs and the type one and L. I'll turn it over to Claire. You're still there? You don't have any more? All right, thank you. All right, thank you, Jay. From all the real-life experience on blending the PLC with type three, where case is just completely 100% replacing type three or type one with PLC. So just a few pretty pictures on my part. We think the future is now. We see the procurement policy already coming through different levels, and we see the tables, the GWP requirements already out there. The common theme is, next slide, is how can concrete get greener? So we believe in a science and evidence-based approach to lowering the embodied carbon of concrete. I think Jay did a great job, kind of break down the concrete by its each ingredients and provide you an opportunity to see where in these components that you can reduce your carbon. So I think the strategy is increasing our efficiency, where we can find opportunity to increase our efficiency, whether through the aggregate skeleton gradation or utilizing atmospheres, accelerators, or high range water reducers, you name it. This may be not prevalent to precast and pre-stress. For ready-mix world, on day of maturity, we see a specification are trying to allow that to be on 28 days and definitely utilizing both supplementary cementitious material, which is oftentimes recycled and poses lower embodied carbon. So this is another pretty pictures, just trying to flow how we are advancing our mix design, optimizing at each component and each level. Next graph is going to be a similar way, just on a waterfall type of graph and visually kind of help you understand how we are chipping away the embodied carbon step-by-step and eventually, hopefully achieving the carbon neutrality. So here you have a gray traditional concrete using a type one, two, or general use cement by simply switching to PLC and you will reduce a certain percentage of your embodied carbon kilogram per cubic meter. And to advancing that, we add more SEMs and another is increasing the SEMs and pushing it and reducing your paste content by optimizing your aggregate gradations. And this could be on day of maturity. Again, maybe not prevalent to this audience, but it's a way that's being discussed among our bigger design community. Again, increasing the SEMs by allowing the concrete product to mature later. And there are other ways more advancing that we should be expecting the marketplace to keep innovating and providing solutions. And atmospheres, there are type S atmospheres that's providing value to reducing your carbon as well. Next slide. So just to pull the lenses with a broader field of view at Lehigh Hanson and Heidelberg Cement, I think this is our roadmap kind of closing the carbon and material loop. So encouraging all the producer out there and trying to see where you guys can find opportunity to be innovative. And our roadmap is closely aligned with PCA and on GCCA roadmap as well. So one more thing I think is really neat with precast and pre-stress industry is there's a manage. All the precast and pre-stress are durable and they last a long time. And so I saw some talking about adaptive reuse. Here is example of a parking garage, maybe not used often or due to traffic pattern or car sharing. It can be reused to just due to the durability and longevity of the structure. Here is example sketch from a parking garage and adapted reuse into a mixed use building. And another thing is precast and pre-stress is part of a modular construction. So if you read Building Green and they stated a common sustainability benefit for modular construction include all these things that we're trying to going after, either reducing waste, poor safety and reducing operational carbon as well. So I thought that's really unique to you guys. With that, I think that's all our prepared materials. Thank you. Thank you, Claire and Jay for a great and informative presentation. We'll start the Q&A portion of our presentation right now. We have a few questions. The first one is how will sulfate resistant concrete be handled? In higher sulfate areas, we need to be able to use MS and HS cements. This easy one, I can take it. So just like Jay was mentioning, Portland Limestone Cement that flows in ASDMC 595, which is a blend cement also is a performance-based specification. So it allows us on to not, it is no longer unregulate our performance like a chemical based, it's no longer going after calcium C3A content. It goes by a performance-based approach. So upon the result of C1012 data, you will see nomenclature such as type 1L bracket 11, MS, MH, meaning type 1L Portland Limestone Cement with 11% limestone addition, moderate sulfate and moderate heat. All right, thank you. We have another question here. Hold on, quite a few. Oh, that's a long one. Well, you know, we have enough time. I'm going to see if I can actually get through this whole question here. It's a lot. All of the comparison mixes between type 3 versus blended cement profiles seem to assume total cement content is the same. Has there been, have there been any studies showing eight hour or 12 hour springs being the same and increasing total cementitious content to see what that blend would have to be? For example, if you have a mix that needs to be 3,500 PSI in eight hours, and you can get that with 750 pounds of type 3 cement, what would be the mix? What would the mix be using a 70-30 blend of type 3 and type IL, maybe 850 total pounds of cement at that blend? And if it takes increasing total cement, does that actually lower net embodied carbon? Hopefully that made sense to you all. Yeah, definitely made sense. Thank you for the great question. That's a well thought out question that we have struggled with. So that tension that you kind of revealed there with that question is evident. We are getting faster strengths with our type 3 that's really hard to reproduce without using that fine of a grind. So if you're getting a type 3 at one level and you have to add more cement to the mix, once again, it's kind of fighting against the carbon footprint. I agree with that. Whereas the type 1L comes in, there is a point to where if you're adding a little bit more, you still got the same carbon footprint, but I like to go better. I mean, I really do. We've got a couple of mixes that we've gone on site, and that's where we did the experiments with an accelerator. So we're finding that we're going to have to be more creative if you're going to hold the cement, total cement at 700, let's just say that. You're now going to have to use things to bump that strength, to get it moving faster. Eight hours is really tough. 70-30 seems to be a really good blend that we're seeing out in the field. For the cooler months, the summer months, we're backing off even further. So I think I danced around the question without really asking it directly, but we are aware of that tension and we want to do, we don't want to add more powder to the mixture. I've done enough testing in the lab and then in also the thermal profiles to see the difference. But to me, the easiest is use of add mixtures in that realm. And then you start getting into, let's figure out what our mix design can do. Okay. Thank you. Next question is, have you tried PLC and UHPC? Have you done that yet? Claire, have you done that yet? Not yet, but I think UHPC has a lot to do with particle size distribution. Yeah, we welcome any opportunity to work together on UHPC with PLC. Hmm, right. I haven't done it in the lab yet. It's very, very tough to go that route, but we have had one person reach out to us for some material for some testing. So it's relatively new. Okay. Next question is, would the Blaine be higher and by how much? Hmm. I'm going to assume the type one compared to the type 1L. And right now the Blaine is typically about 40 to 50, 60 points higher. Puts that into some numbers. 400 is if your straight cement is there. We're getting comparative results down in the 440, sometimes even 420 range. It just really depends. It's more cement plant dependent, that question. And then we're also, we are still refining that in the States here. So I can't speak for Europe and whatnot. They've been doing this a lot longer than us. Okay. Let's see here. I asked this question already. Yeah, that is part two of that one. Is there any thought of making a type 3L? Great question. I tried to put that into the presentation very subtly. That's why the blend has come on board so heavy. Right now the main concern is getting type one switched over. I can't speak for other cements out there, but I can speak for ours. We are experimenting with this and our hope is to create a product that the precasters can use. All right. Next question. Is there a plan to have a type 3L for high early strength? Is that the same type of question we asked there? Yes, sir. Yeah, same type of question. Translated, it came in a different kind of format. Let's see. I believe that might be all the questions that we have. We have one more question, but I think you touched on this. It says the graphs were tough to look. The graphs were tough to tell the numbers on, but it looked like you showed 12 hours strength to be about 400 PSI lower with type 1L versus type one. Is that correct? Yeah, with that particular cement, that was correct. We've got some other cements that I have tested that have been equal, but 12 hours is a little bit tough because of the makeup of the chemistry in both. So you are correct for that particular cement. We've got other examples to where they're equal, but I had data on it for that particular project. All right, we just had another question come in, and it is what is the recommended curing temperature range for these mixes? Oh, geez. I would resort back to anything from PCI and what they've recommended. Obviously, you've got your cap of 165. We don't want to be over that. So you've got your preset times that we're still holding true to. So I would follow those guidelines. All right, well, it looks like that's all the questions we have. On behalf of PCI, I'd like to thank Claire and Jay for a great presentation. I'd like to thank also our attendees for their participation, and also let everyone know, if you would like to ask questions after this ends, please send an email to marketing at pci.org, and we will forward all the questions over to our presenters today, as also there is a pop-up survey after the presentation ends. Thank you all, have a great day, and please stay safe.

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