 Well, I'd like to welcome everyone to this celebration of faculty careers for Jan Olick. This is one of many in a series that we're having. It's part of our post-10-year review process that's occurring within the College of Engineering. Maybe I should mention just a little bit of background on that and maybe before I do that. But I'm so comfortable with this audience because I know you all for the most part. But I'm Robert Frosch. I'm Associate Dean of Engineering for Resource Planning and Management. So I'd like to welcome you here on behalf of the College of Engineering. Again, talking a little bit about post-10-year review is a process that the College of Engineering initiated several years ago. And so for senior faculty, faculty that have been promoted for past seven years past their promotion, we're regularly doing these review seminars. It's a celebration of the progress that Yana's made over his career. So he'll tell us a little bit about what he has done in his recent past, as well as kind of the history of what he's been doing. But then it's also charting the course for the future, not just where we're stopping and celebrating today, but celebrating what his future successes will be and how he'll move off into the future. So past this process of having this seminar, Yana will also be meeting with the head of the school, GS, and he'll also be meeting with Leah as the Dean that talk about kind of his future plans and where he's headed with that. So that was just a little bit about the background of this symposium. The other thing I wanted to do is obviously introduce Yana. Yana's been a colleague of mine now since I started here. He was here slightly before I started here in 97, and I was looking back in here, it was 1994. So I knew you had just started a little bit when I first started back here in 97. And actually when I first met Yana was before that, turns out I was a student at University of Texas Austin because Yana has some connections to UT. Yana did his master's degree there in structural engineering. And before he actually has another master's in airports pavements right from Krakow University in Poland. So again, I had a connection at UT, but I was at, I think it was Salt Lake City, ACI, and I think that was where I first met Yana. And he was at Penn State at the time as a faculty member. So I've known Yana actually for quite a few years. And since being at Purdue, we've actually collaborated on a number of projects, both research related as well as actually some consulting that we've had to do for helping out the Yana Department of Transportation. So I consider Yana a good friend. And so I've known Yana again for many years. And we also love concrete. We're both in the concrete area. And we devote a lot of time to ACI. And so we always, besides being here on campus, we get to see each other at conventions. And we'll be in about a week or so and we're off to Milwaukee. So without further ado, I really wanna celebrate Yana's faculty career. He's been again with us for over 20 years now. Yana, looking forward to your presentation. Thank you very much, Robert. I think I'm mic'd, so I should be hopefully recordable. And I hope you can hear me without the mic. This room is not that big. Well, thank you very much everybody for coming. It's a wonderful opportunity to share with you what I've been doing for, let's say 20 plus years. And we'll see what directions I have in mind as far as the future remaining years of my career. A little bit about myself for those of you who don't know exactly where I come from. Robert already introduced me and mentioned that I came from Poland. I was born in the city of Krakow. And that's where I went to school and I got my first two degrees there, Bachelors of Science and Master of Science in Civil Engineering in what's called Krakow University of Technology. And in 1982, I guess it was, I got a Fulbright scholarship to study in the US and I came to University of Texas at Austin, about 6,000 miles from home and spent about two years there. I got my Master's degree there in Sexual Engineering. And I really like working with materials and applications to infrastructural components. And I was talking to my advisor, Dr. Kara Skidio, at the time and I said, you know, what would you recommend for a good materials program? And he says Purdue University. And I said, where is Purdue? And he didn't know exactly. Which was a little bit alarming. But we took the Atlas out, that was before the internet and we figured out it's in Indiana, so I actually flew in here to a scoped place. It was in January and it was a heavy winter and coming from Austin, it was a shock. Small town, completely covered in snow. The small airplane landed at Purdue Airport and I barely could see the road. But anyway, the program was good, so I decided to come. So I got to Purdue to work on my PhD. I got here in 85, graduated in 87. And for the next few years, I was kind of wandering all over the US. I got my first faculty position at the Colorado School of Mines. So I spent about three years there. And when I was there, I got a phone call from Penn State and they said, well, you are at the program that really doesn't have a big research component, which was true. There were departments at the Colorado School of Mines that were very much research oriented, but the department of engineering or division of engineering, as it was called, was not. There were three young faculties there that we were trying to put together a graduate program. We didn't have a graduate program. It was difficult to compete with all the well-established program for tenure and promotion if you didn't have graduate students and didn't have a research. So I took the opportunity and moved to Penn State. And when I was there, I got an offer or invitation to come back to Purdue. I obviously knew the place and I very much liked the faculty members who were here and the labs were fantastic and decided to come back. So that was back in 1994 and I didn't move yet, okay? It seems like everybody seems to be moving around. Anyway, what do I do? I kind of like to think that I work in the area of durability and sustainability. And the reason I work on that is because of interest to me, but it's sort of an underlying theme of what's happening in the cement and concrete industry. So over the years, certainly during my career, there's this growing interest in focusing on durability and sustainability. And that has various forms. Anything from usage of secondary fuels in cement production and this is mostly to incinerate some waste from other industries, in increased usage of industrial byproducts such as fly ash, silica, a few metacol in slag and so forth. New admixtures are coming on the market since like almost every month and the Kelland concrete mixture designer is rather complex because of those admixtures. There's potential for incompatibilities from time to time. So that makes a professional life rather interesting. Probably the most important one in this category is really increasing demand for longer life of the structure. Especially when we are facing a staggering bills for fixing the infrastructure, the question naturally comes up, what can we do it better? Can we do it in more reliable way? And I said, well, you know, this is really a good field to be in because what I am interested in is looking at the micro-structural level and at the chemistry of the system and I know it's pretty critical to making sure that the big elements work. So the title of my talk was durability, sustainability, why is it that the small or little things matter and they matter because of the micro-structure and chemistry that is involved that actually dictates the behavior of the element itself. There is also issue of scale. I mean, we are talking about market that is very, very large. In 2014, you can see that the word cement production was about 4.1 billion tons. That corresponds roughly to about 10 billion cubic meters of concrete we assume about 400 kilograms of cement per cubic meter but associated with that tremendous production of cement is the release of CO2 or greenhouse gas, roughly about one ton of CO2 per ton of cement. So the cement industry produces about 4 billion tons of CO2 which everybody is worrying about recently, right? On the grand scale, it's really not that much. It's about 5 to 8% of global CO2. The other industries including automobiles produce more but it's not negligible, right? 8% is still a pre-sizable amount. And the fact that we have deteriorating infrastructure, economies are predicting that's going to present some drag on the economy in the future. So seems like right now is a good time to start worrying about those things and more people do worry about those things. I thought being the university as a home to the astronaut, I need to make some analogy of concrete usage. If we make six in diameter concrete cylinder which is a standard cylinder for testing, we can reach the moon four times a day. That's how much concrete we are making, right? It's 230,000 miles to the moon. So imagine four cylinders six in diameter dead tall. So there is a lot of money at stake. There is a lot of infrastructural components that are affected by what's happening. So this is supposed to be about my research interest. So my research area are really traditional and novel supplementary cementitious materials. And to a small extent, I work in the asphalt areas. So thank you very much for coming. They represent the black side of the civil engineering as opposed to the white side represented by concrete. I worry about durability of concrete, performance in concrete, and all this is obviously interrelated. More specifically, what I work on is on advanced characterization techniques for cementitious materials. I worry about microstructural properties and the effect on performance. I spend a lot of time on mechanisms of deterioration, trying to understand what those are and trying to come up with some models that can provide information about future performance based on what I learn about the materials from this bullet one, and based on what I learned from bullets two and three. So it's difficult to summarize in 50 minutes or so everything that I've done. And you would be bored, I'm sure. Even though it's an exciting topic for me. But I will talk about few items that I spend probably the most time on. The issue of fly ash and other supplementary materials is something that I've been working on for the last 30 years. My master's thesis was, my second master's thesis was dealing with fly ash. And throughout my professional career, I've done a lot of different research projects that are related to those materials. So this is the SEM image of the fly ash. This is the silica fume. You can see nice little round spheres. And, you know, those are other metacol in natural pozzolans, slag and so forth. I wanted to talk a little bit about fly ash because fly ash is one of those interesting materials because it's a byproduct of cold burning in the power plants. And it's being captured and in 1980s, the power plant will actually pay you if you wanted to take it off their hands because they had to store it and they had to build a big storage pond that, you know, environmentalists were not happy with the storage and nobody knew what to do with it. Once people determined that they could be beneficially utilizing concrete and actually improve the properties of concrete, the companies emerged that started marketing the fly ash. So they will buy the fly ash from the power plant. Power plant is a business of making power and not worrying about the fly ash. They will be sort of intermediary. They will buy that from them, maybe do a little bit of classification or some sort of enhancement of the properties, very minimal, and then turn around and sell it to the cement producers or to concrete producers. We typically, sorry, we typically talk about two types of fly ashes, type F and type C. Type F is what we call a low calcium fly ash. Type C is a high calcium fly ash. And they are actually quite interesting when it comes to how they influence the properties of concrete. Class C fly ashes, for example, are not very good with respect to addressing some of the durability issues of concrete. Class F, on the other hand, is very good but it's not as, you know, with respect to durability but it's not very good with respect to reactivity. But you can see, looking at the chemical composition, that they have typically calcium, silica, alumina, and ferrite, some sulfate, and alkalis. And you can see class C has much higher percentages of calcium than class F, but there are calcium, silica, aluminates. Cement components are also calcium, silica, aluminates. The amount of calcium to silica, the ratio of calcium to silica and the cement is very high in the fly ash, it is not. But they are somewhat similar with respect to chemistry. Therefore, one would expect that they will work together well in the system. Morphology of the fly ashes is something that people who work in the area worry about a lot because it is influencing the properties of concrete, especially in the first stage, once you start adding it. So you can probably imagine that you have nice little spheres that will behave very different from something that looks like that that has, this is the unburned cold particles that for example will have very negative influence on the amount of air that you can train in concrete. You may have a system where you have a lot of small spheres in the bigger spheres. Notice that the sphere looks kind of a glassy and glass is actually a reactive component of the fly ash. Composition of the fly ash determines how effective the fly ash is going to be with respect to impairing certain properties on concrete. For class C fly ashes, they tend to be cleaner. If you look at the surfaces that are more deposits free, if you will, and they are typically very good, they have very often a lot of fine particles that are very good with respect to workability. They also tend to be quite reactive. The glass, the type of glass that makes the sphere is more reactive than type of glass that is present in the class F. The standard thing to do if you want to know something about the reactivity of the fly ash is to determine by let's say XRD or other technique the amount of crystalline components and the amount of glass. The more glass you have, the more reactive the material. Most of the components that are crystalline that show as a peak over here are typically non-reactive. So you have quartz and molyte. Those are not reactive. But what I wanted to draw your attention to is this hump here that you see that represents the amount of glass and if you look sort of as the highest point or the medium of this hump for the class F ashes, this is located at about 25 degrees to theta angle when we do the XRD experiment. If you move to class C ash, notice that that hump is about 30 degrees. That reflects the differences in composition of the glass and therefore in reactivity. So I actually spent quite a bit of time trying to capture the differences in the chemical composition and how they influence the location of this peak and in fact the size of this peak because fly ash is a byproduct. Nobody really controls the quality of that material. And if you are a user of that material, you would like to know whether a batch to batch to batch will provide a consistent performance. Do you need to put more or do you need to put less? And how do you quickly determine that? And for years, people were trying to link the chemical composition with mineralogical composition via various models, including us. And I think the chances of doing it now is higher than ever because in addition to doing what we are doing here with simple XRD classification, you can also do a more involved classification or evaluation using scanning electron microscopy where you can do on very micro level determine the distribution of various phases, various chemical components and combining those various techniques gives much better prediction with respect to performance of the material in concrete. So we attempted to do that. We developed quite a few models that were focusing on the glass content, both estimation and composition and got reasonably good results. This is one example, for example, which shows the predicted set time based on the chemistry of the fly ash. Of importance to the users because class C fly ashes in particular very often tend to extend the set time. And especially the temperature drops and you have a material that you use that has extended set time, you would like to know. Sometimes the admixtures interact with the components of fly ash and extend that set time further. So maybe you would expect that you can come and start finishing your slab in three hours and a day later it's still didn't set. So that's the problem, right? So if you can predict that, that will be helpful. We use those models for helping with development of performance-related specifications for both bridges and pavements. And that involves both material selection, mixture composition, durability and performance. So I will spend a little bit of time talking about this. And this is really focusing on the durability issue. So deterioration of bridge decks or pavements, especially if it's premature is of concern. The typical environmental conditions that contribute to this deterioration is anything from corrosion of reinforcement to freestyle damage to scaling, which would be the damage in the presence of the icing chemicals. Traditionally, people were trying to take care of that durability issue by specifying or controlling where cement ratio. But prescribing a minimal cement content which very often produced the mixes that were too strong and actually created additional durability problems with respect to fatigue or cracking tendency. So right now, people are trying to move away from that and trying to specify something else, specify some performance characteristics. But how do you achieve those? If you are using some of those supplementary cementitious materials, it's a remaining challenge. So I work a little bit in that area focusing on enhancing the durability of concrete, especially when we started that work, there was very little guidance available how to achieve certain performance characteristics if you try to mix maybe two or three of those supplementary materials together. Why would you want to mix them? Turns out there is certain synergy between various materials and what you are getting in terms of the output is bigger than the sum of the two components that went in. So that's obviously beneficial. So let's talk a little bit about a couple of projects. One was in developing proportioning method for mixtures with predictable performance characteristics, identification of optimum content of the binder to achieve those performance characteristics and evaluation of mechanical properties and ultimately modeling those predicted mechanical properties over time. In high performance concrete, there was a term that was hot maybe 20 years ago. Now that high performance concrete is actually a regular concrete now, technology changes. But majority of binder was potent cement, people use silica fume, flash and slacks. So we thought, well, how about if we try to combine two of those in addition to cement in any order? Would that be any benefit? And how can we do that? And so forth. So if you look at those variables, well, if you look at the amount of materials that you can use and if you look at the percentages of those materials that you can use, this really presents a challenging experimental problem. You cannot do all the possible combination that wouldn't be a smart way to do it anyway, right? So you try to do what we call the experimental design and select the minimum number of mixes that when you make and evaluate the properties will allow you for statistically valid analysis of your data and making some sort of a statistical predictions models. So one of the things that we've done, those for bridges and for pavements that we use this technique called surface response methodology to determine properties as the function of, you can see what are buying the ratio here. You can see content of silica fume and content of fly ash. So you can see that various colors represents to various ranges. This is a total charge in coulombs. That has to do with the resistance of concrete to Inglis of chloride, which is one of the concerns in the durability. So if you wanted to have a really low coulomb value, you want to be in this region and so forth, right? So that was helpful for recommending certain practices or certain specifications to the DOT in terms of how to go about selecting the material. We've done similar thing for pavements, this involves the slag, which is another byproduct and silica fume. So there's a mix that has potencymin slag and silica fume. We actually develop a little model that allows you to put the values of the expected performance characteristics. Let's say you want 5,000 PSI concrete at 28 days or 10,000. You want that value of rapid-collar permeability or resistance to chloride. And that model will, for given war cement ratio, water binder ratio, will actually give you the recommended percentages of supplementary cementitious materials or the composition of the binary or ternary mix that you can use for that. And the model is obviously only as good as the data that you put in. We've done, as I said, statistical planning of experiment and statistical evaluation when the real proof came from actually looking at the performance of the actual constructed facility. So we had several bridges, you can see them listed here, where both us and Indod were running the test to determine whether we agree with the values. I guess they didn't completely trust us that we don't rig the outcome, right? And we're looking at quite a number of, high number of specimens. And then we're looking for verification of the model. And you can see that, for example, with respect to the current that was able to pass to the concrete, the model prediction there in the black lines there matched the data pretty well. Considering that those were totally different mixes that we didn't do, didn't have any control over, I was pretty happy with that outcome because it means that the model based on combining the material characteristics and evaluation of contribution from individual components to define our outcome actually worked. I mentioned that we also were able to account for some synergistic effects between, of interaction between various components. And we were actually able to classify or quantify the amount of this synergistic contribution. And if you look at the predictions, especially in 180 days, this, for example, for initial absorptivity or for rapid hypermobility, you can see that the values that were predicted and the actual values here were pretty close. Again, a good tool for using these models and coming up with some performance characteristics that you can actually put in the specification. We developed several methods for those validations. This is the example of the predicted versus measured rapid hypermobility based on the maturity method, which was another model that was built up on the previous models with respect to the usage of the flyers that I described earlier. About 10 years ago, maybe 15 by now, all of a sudden a new problem surface and there's always this new prep, new problem that gets us excited for about 10 years and then it kind of fades away. So everybody was saying, sky is falling, sky is falling. We have a problem with the ICERs. The pavements in particular started showing sign of premature deterioration and everybody was blaming at the ICERs or the icing practices that reflected the need for, better methods of controlling guys in snow because of the increased traffic. So the ICERs, they were more aggressive toward concrete. And it turned out that fly ash, there's byproduct that is being used in concrete actually protects the concrete very well. And this is a good example. This is the fly ash specimen, it's 20% fly ash. This is just regular plain concrete. And you can see the amount of deterioration that is happening in the plain concrete with respect to the fly ash. That was, it took some convincing of DOTs that actually using a fly ash is good for that purposes. The problem that typical contractor working for DOT faces is that come October, contractor is not allowed to use the fly ash anymore because concrete with fly ash takes longer to develop strength and they were afraid that if that concrete is salted in early fall, there'll be damage and they didn't allow the contractor to use fly ashes. So every October there was a big shortage of cement because everybody who was using 25% of fly ash of the sign had to switch and they needed cement and cement was in short supply. So we were trying to say, listen, we can use some of those model to predict the extent to which the fly ash will actually react and be able to actually give you some sort of assurance that with certain fly ashes you don't actually run the risk. So initially DOT said, okay, we will extend the deadline or the ban on using the fly ash by one month. So not October, November, but the contractor has to take the entire risk. If the pavement goes bad, it's a contractor's responsibility. So the contractors obviously didn't want to do it so nothing was changing for a while until those super deicers came on the seam and the damage caused by them was more than the damage that you would expect from just using the fly ash late in the construction season. And finally, Indiana right now doesn't have a limit on when you can or cannot use the fly ash. He didn't know he did that about 10 years before Indiana even though we have a similar climate. Well, the other area that I was working on and still working on is having to do with another little bit of a problem that's called alkali silica reaction. This is my favorite picture. It comes from Winter Park where I go skiing every year or try to. And this is a six mile long tunnel on the Rocky Mountains. And this is the train, ski train actually coming from Denver and coming to Winter Park. And if you look closely, you can see this block cracking all over the place. And it's a classic example of alkali silica reaction. You can see the tunnel was built between 1923 and 1927 since it was almost 100 years old. So it has the right to deteriorate your living, right? And this is ACI meeting in Kansas City. Robert will probably remember we were in the hotel that was surrounded by the concrete plaza that had all kinds of problems with ASR and corrosion or reinforcement. I didn't put it here but there was also some picket line and we're staying in Hilton I guess as the conference was and the people had big transparencies and Hilton has rats in their hotels. I don't know if they were referring to the ACI participants or actual rats but anyway. I didn't see any but I see a lot of ASR and I wanted to share with you a little bit about studies that I've done on that. So alkali silica reaction is actually a process where you depolymerize and dissolve reactive silica that is part of your aggregate and that product forms a hydrous alkali silica gel that gel attracts the water and swells and exerts the pressure that causes the cracking that I showed you on the portal of the tunnel. There is a general agreement that there is a chemical reaction that the chemical reaction is necessary to form this gel but there is not a general agreement on what is the sequence of steps that lead to formation of this gel and there is also not general agreement about the mechanism of expansion that causes the pressure that carries the concrete. So for the last six years or so I've been working on that with several of my students where we try to look at the process in its entirety that is from formation of gel trying to understand the chemical reaction and the kinetics of those reactions that lead to the formation of the gel and then look at the mechanical response on the micro and macro scale. So this is looking at the macro scale or micro scale I should say and you can see that you have deposits of gel you can see that it's a calcium silica and oxygen and you can see the sodium here and traces of potassium typical alkalis that are responsible for formation of this gel and you can see that it causes the cracking of the aggregate and the crack propagates into the concrete so it could be a pre-damaging kind of scenario there is a series of pictures that as you go from left to right we are increasing in age here and you can see that after some time you start forming those cracks in the interface between the matrix and the aggregate you start depositing gel in the pores if you look at the structures that are really severely affected by that like dams for example where there is a lot of water there would be this whiteish gel oozing out of the pores there are some dams in Canada Canada has a lot of aggregates that are susceptible to that there are some dams in Canada that grow about 5 inches a year because of the expansion so they keep cutting the slices of concrete to make sure that it doesn't crack more so I wonder how long can they cut until they cut up to the point that there is nothing left but it's not an easily fixable problem one of the tasks that we've done and I think it turned out pretty well was determining the sequence of the chemical reactions that take place during the ASR and if you look at this graphs very briefly you can see that this is a residual amount of one of those reactive aggregates crystallites in gram and you can see that from very beginning it kind of has downward tendencies you can see that the potassium ions stay more or less steady at the same level potassium ions are very low stay more or less at the same level but notice that we are decreasing the amount of calcium hydroxide calcium hydroxide is plentiful in regular concrete this is a byproduct of cement hydration so it's always available we had the system which we were trying to start out of CAO sorry, calcium hydroxide to see what the role calcium hydroxide plays and then you can see there's a practically constant level of pH if you go and look at what is produced during that phase we were producing calcium silica hydrate gel we call it but this is actually a matrix that bonds the aggregate together in the regular concrete so this is a glue, that's a good stuff and when we go to assessing the constants for those reactions kinetics constants you can see that they are linear with respect to the amount of the dissolved silica with respect to time in both potassium hydroxide and sodium hydroxide solution we go to further in time to what I called zone 2 and zone 3 something interesting happens notice that all of a sudden silica concentration in the pore solution starts picking up the dissolution of silica practically stops pH changes and we depleted the amount of calcium hydroxide so that actually gave us a very good indication of what is happening in that system we were able to determine that the originally produced calcium silica hydrate gel actually changed to some form of gel that campaigned alkalis and it's more expansive and so forth so from further modeling the entire sequence of events in this particular situation so the step one was the formation of CSA gel then formation of disamorphosis alkali loaded gel then we had continuous increase in concentration of silica ion and finally we produced the gel in this part and that's the gel that will be expanding so those were the observations in the lab what we wanted to do is to build the model that can actually predict that so we look at the rate model that involves mass transfer and has all those parameters it was a pretty complex model but it worked very well you can see over here all the data that we collected versus the predicted values that are in the form of the continuous lines there were quite good and those are the modeling results those are the results that we got from the experiment that I just showed you and the general shape of the curves and the location of the phases is very similar so we said that we have this tool what can we do with it and what we propose and that was a project funded by Federal Higher Administration and NCHRP we said you know why won't you try to see if we can predict the existence of what is called a threshold alkali concentration concentration of alkalis that will not cause ASR and the concentration was about 0.26 you can see that based on our model prediction all those curves asymptotically approached that and that was a good verification that the model actually worked we propose a new test which we called a new quick chemical test for checking the susceptibility of the aggregate to this degradation process and the criteria that one can use for that purposes and actually look at about 10 different aggregates that other people determined are reactive and we predicted all of them as being reactive based on somebody else's data so that also worked right to be good that's what I was doing for as I said for the last 27 years now what my plans for the future are so two groups of topics I am working on right now is one has to do with sorry alternatives to traditional cementitious binders so we are looking at low lime to silica binder that is solidified by carbonation as opposed to hydration and I recently got involved with Pablo and Jeff Young from material science and some people from other universities on what we called additive manufacturing on 3D printing so let me spend a minute or so talking about this carbonation driven type of alternative cementitious material the process of carbonation of lime has been known for millennia all the old buildings are bid using lime mortar that carbonates when exposed to air in the 80s people were looking at accelerating hydration of regular or hardening of regular port and cement by exposing CO2 we are working with a startup company in New Jersey called Soligia Technologies that uses non-hydraulic binders that are produced in the same way as the port and cement is but at the lower firing temperature so there is about 30% reduction in CO2 emission because you don't need to decompose so much calcium carbonate and you use the same material but lower in calcium carbonate that you use for production of regular port and cement and you essentially put the dry cement in you cover it with film of water CO2 dissolves in that film of water and you have sort of a counter diffusion CO2 goes in, water goes out and what you produce is there is green stuff, there is calcium carbonate and that gel is a byproduct so that actually was very interesting to me because the nature of the silica gel is very much similar to the nature of the silica gel that we see in acrylic silica reaction and we already had some models that deal with that so I thought it would be interesting topic to work on and it's very exciting we've done a lot of characterization of those materials using various advanced techniques to decipher what kind of product we are forming initially that product had a problem with keeping strength when it got wet so it was 10,000 when it was dry 10,000 psi when it was dry, 4,000 when it was wet so not very useful, right? by looking at the actual type of gel that forms we were able to advise them on changing the way they actually cured the material and the way how they select the size of the particles that go into the reaction and they got essentially no strength loss right now if you look, if I can go back here for a second notice that there is a pretty large pore in the system that forms which typically doesn't form the regular portansin system so the size of the particles that you use needs to be optimized so you have a better packing so you don't have to feel such a big gap as you would the durability of that new cement is very good this is a comparison of specimens from portansin that were exposed to sodium sulfide solution something that you may expect in Nevada or California where the groundwater has sulfides in it and this cement performed very well we've done a lot of investigation of the actual reaction products and developed a pretty good idea for the model that is currently being tested with respect to the optimizing the curing conditions to solidify this material and finally this is a new adventure we just got the collaborative NSF project funded it's a joint venture between Purdue, Tennessee Tech and Vanderbilt where we are looking at 3D printing as a tool for development of multi-scale hierarchical microstructure of cement-based material the idea is that if you could put components that are of importance let's say fibers that can carry the tensile load or something like that just in the place where you actually need them rather than putting them everywhere you will engineer the microstructure that does exactly what you want it's an easy problem because you need to worry about placing the material in the right spot you need to worry about the interfaces between whatever components you use and pretty much the only way you can do it with high enough precision is to print it in place so we are looking at the development of the prototype equipment we are also looking at processing conditions the formation of the printing media and ultimately we are looking to modeling, that's Pablo's part of the performance of the material that we hope to produce so this is all I have I wanted to officially thank all my students that helped with all this work all the collaborators that I had over the years all the sponsors who made all this possible my wife who is over there very supportive she doesn't want to be put on the spot I am sure but I will be remiss if I didn't mention her enduring support that helped with that with this, I will finish and if you have any questions I will be glad to answer we must have some questions no one came with the notebook because I think you have done excellent research and gave a very good example about how to do high impact research combine a fundamental science and engineering application so what do you think about the nanotechnology in cement or concrete for the direction wise so nanotechnology has been this hot topic for the last ten years in cement and concrete and everybody was trying to use it and I think people didn't really approach it correctly so it took a little bit of a setback in my opinion, the reason people didn't approach it correctly is because it was such a hot topic in all the other fields that people say let's throw something nano in concrete and see what it does and really not approaching from the fundamental type of perspective I think people who try that very quickly realize that it's just too expensive and the payout is just not there but there are other people now who are trying to approach it a bit more pragmatically looking at the science behind it I think was the proper fundamental research that could be maybe a niche type of material but I think it could be quite unique considering the versatility of concrete and the large amount of concrete that is being used anything from sensing to energy harvesting we actually I'm looking back we had a proposal for the center that was focusing on charging the electrical cars on the fly as they drive over the highway and I was secretly hoping that we can put some of the nano materials there for energy harvesting purposes unfortunately we didn't get the funding the core group of people who started it are kind of working on it still maybe we'll go and try it another round I think that part of the reason we didn't get funded is that we hid the cheap gasoline who cares about the electrical car mentality so I'm waiting for the oil crisis to to jack up our chances yes in your presentation you talk about the problems that are generated into these materials and basically how we design the materials such that so what are all your thoughts on the problems that we really have example of iteration how we can teach those where the research should go to teach what we have to design new materials so the research in the area of maintenance and rehabilitation it really is focusing on cladding materials rapid setting materials I think the field of rapid setting materials in particular has a lot of potential the reason for that is that again right now the way it's handled are proprietary producers of those rapid setting materials that will promise you anything and then when it actually comes to application it really doesn't work it only works for a very short time and part of the reason for that is that there's a too big of incompatibility between the properties of this new material that forms in situ and the existing material we are not trying to remove the underlying causes be the elevated level of chlorides or being micro cracking or something like that so I think anything that will combine it's not a self healing but some sort of the healing of the existing structure to the point that is more compatible with those new materials would be a great field to go into the problem is that I'm not sure who will fund that we have to sequester some of that 4 billion tons absolutely so a cubic meter of this new concrete sequesters about 300 kilos of CO2 ideally we are not there yet ideally what one can do is build a some sort of the concrete plant right next to the cement plant and take the CO2 that escapes from the chimney right now and use it for curing that material in the city we are working on the potential for carbonating in the field right now but really the immediate application and that's what the company is actually doing it has licenses already there's quite a few precast concrete manufacturers is to use that CO2 in the precast concrete plant where you can build the tent around and create the right conditions the purity of CO2 is an issue and right now since we don't have really a carbon tax in this country the producers of CO2 are not motivated to clean it and the way it comes out is really not suitable for the effectiveness in carbonation wouldn't be high enough so this particular company buys a CO2 from the producer that cleans it before releasing it and it's a metal producing business but ultimately if the economy is right there will be incentive perhaps to clean that CO2 and be a little bit more efficient in using what we produce Europeans have the carbon tax and you know the climate conference in Kyoto that was what ten years ago the US did not sign the newest treaty I'm not sure I think they did sign but it will probably take a few years before it percolates down to the executive level I'm going to go back to the beginning with fly ash so obviously we all know now the great benefits of it in fact some are using 50-60% replacement but now going back to the CO2 issue coal was dropped dramatically actually I think in the US right now it went from 65% it's below 35% of all energy so there's now huge shortages of fly ash I was just in New York they can't get fly ash at all right now so what are we going to do to replace fly ash because it's a valuable tool in what we can do for durability and strength I think there are two things we can do one maybe the most obvious is that there are tons and tons of stockpiled fly ash provides supply at the current level for the next 30 years if we wanted to touch them they were laying in various deposits long enough that there is a worry about heavy metals that will settle at the bottom there is a worry about cause of drying them because they are very often in the ponds there is a worry about some of those early pundit fly ashes having too high of a carbon content to be useful so there will be a cause associated with processing but considering the benefit of that material I think when again when the prices are right that will happen and we'll try to reclaim what we stored over the years the second approach and there are people who are actually very proactive in that is the production of the artificial artificial pozzolans again you can do that from the same materials that you use for production of cement at much lower temperature and in fact the company that we work with on this solidia cement they are already filing for patent for producing artificial pozzolana which would be actually a byproduct of their friendly cement production so I think people realize the benefits of having something that consumes as exocasium hydroxide in concrete and whether it's artificial, natural or reclaimed they will try to use it Any other questions? Hearing none I'd like to again thank you Thank you