057 - Structural fire engineering with Thomas Gernay

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<v Wojciech Wegrzynski>Hello, and welcome to the fire science show.

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<v Wojciech Wegrzynski>Episode 57.

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<v Wojciech Wegrzynski>Hope your guys are having a great summertime and some fire science in between will not hurt for sure.

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<v Wojciech Wegrzynski>Today I have a subject that's quite difficult and, me as well, I don't have great expertise in this.

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<v Wojciech Wegrzynski>So I, I was very happy to learn firsthand from the world, leading the expert, and the topic is structural fire doing and structural fire modeling.

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<v Wojciech Wegrzynski>in fact, I've invited professor Thomas Gernay from John Hopkins university to.

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<v Wojciech Wegrzynski>Bring me in line , on the, how structural fire engineering works.

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<v Wojciech Wegrzynski>What's the newest developments in this field.

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<v Wojciech Wegrzynski>And, what's the future in front of that.

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<v Wojciech Wegrzynski>Thomas is well known for his considerable amount of knowledge put into the world of structural fire engineering literature.

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<v Wojciech Wegrzynski>And he's involved with one of the primary structural fire engineering codes that is severe.

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<v Wojciech Wegrzynski>so he has first hand knowledge, not only from the perspective of a.

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<v Wojciech Wegrzynski>Researcher structural engineer, but also as someone who's developing new tools  for us all to use.

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<v Wojciech Wegrzynski>So that's a really great perspective.

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<v Wojciech Wegrzynski>And you'll see through the interview that we are touching and referring to that all the time, because his perspective is unique.

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<v Wojciech Wegrzynski>So I hope that despite the little summer slack, most of us have, we can join me in this episode and learn a bit about the importance of structural fire engineering.

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<v Wojciech Wegrzynski>And the role that it plays in a performance based design framework.

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<v Wojciech Wegrzynski>Okay.

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<v Wojciech Wegrzynski>I guess that's enough of introduction.

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<v Wojciech Wegrzynski>It's a good episode.

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<v Wojciech Wegrzynski>You want to listen it to the end?

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<v Wojciech Wegrzynski>It's well worth it.

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<v Wojciech Wegrzynski>So let's spin the intro and jump into the episode.

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<v Wojciech Wegrzynski>Hello, everybody.

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<v Wojciech Wegrzynski>Welcome to the Fire Science Show.

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<v Wojciech Wegrzynski>You guys ask.

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<v Wojciech Wegrzynski>And I deliver here with me, Dr.

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<v Wojciech Wegrzynski>Thomas Gernay from John Hopkins University.

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<v Wojciech Wegrzynski>Hey, Thomas.

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<v Thomas Gernay>Hey, Wojciech, how are you?

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<v Wojciech Wegrzynski>I'm very good.

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<v Wojciech Wegrzynski>I'm very happy to have you on the

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<v Thomas Gernay>just, how are you?

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<v Wojciech Wegrzynski>And finally talk with someone about numerical modeling of structures.

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<v Wojciech Wegrzynski>for a nice start.

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<v Wojciech Wegrzynski>I've heard there was a really nice event lately in Italy, summer school on, structural modeling.

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<v Wojciech Wegrzynski>And I keep hearing about this event from everywhere.

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<v Wojciech Wegrzynski>Like everyone is telling me how great it was.

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<v Wojciech Wegrzynski>And, I know the viewpoint of participants.

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<v Wojciech Wegrzynski>Uh, you were one of the speakers there, so, so maybe you can, uh, bring me in line.

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<v Wojciech Wegrzynski>What, what happened in Italy or unless what happens in Italy stays in Italy.

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<v Wojciech Wegrzynski>I dunno.

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<v Thomas Gernay>No, I'm happy to, tell you all about it.

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<v Thomas Gernay>And first of all, thank you so much for having me.

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<v Thomas Gernay>It's a great pleasure.

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<v Thomas Gernay>And I'm a, I'm a fan of your show.

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<v Thomas Gernay>So yes, we had this week long, uh, summer school in Como one of the.

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<v Thomas Gernay>You know, best places in the world, really, really nice location.

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<v Thomas Gernay>in may, that was organized , by dear colleagues at the Polytech in Milan, Roberto Felicetti Patrick Bamonte and Jean-Marc Franssen  was also involved.

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<v Thomas Gernay>So the goal was to bring together, 10 speakers, , for, each of them delivering you have day lecture.

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<v Thomas Gernay>Topic, you know, of their expertise and have, , PhD students and researchers, from all over, get the ability to either come in person or attend remotely.

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<v Thomas Gernay>And it was very, interactive and productive.

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<v Thomas Gernay>It was very nice to be in a room together and being able, not only to, teach about a topic.

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<v Thomas Gernay>Close to what I've been interested recently, but also get the feedback and discussion and get to know what all these researchers are, working on.

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<v Thomas Gernay>And I mean, definitely lots of, very exciting, topics looking at new problems.

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<v Thomas Gernay>so just all  this structural fire engineering community coming together was great.

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<v Thomas Gernay>Um, Yeah, I got , to talk about, the burnout resistance of structures, which is a topic I've been researching for quite a long time.

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<v Thomas Gernay>Actually, that started with my PhD work, where I worked on the development of, numerical model for the behavior of concrete activity, temperature, and.

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<v Thomas Gernay>Paid particular attention to what happens during the cooling down phases.

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<v Thomas Gernay>We wanted to make sure that we were capturing, uh, irreversible processes and damage and transient creep and all these stuff.

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<v Thomas Gernay>And so with these models, then we became able to model more accurately what happened during cooling and whether there was a risk of delayed failure.

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<v Thomas Gernay>And since then it.

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<v Thomas Gernay>Evolved into modeling all types of structures during heating and cooling and, developing a framework to understand when there is a risk of delayed collapse.

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<v Thomas Gernay>So that, that was about, Italy.

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<v Wojciech Wegrzynski>that's a great topic.

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<v Wojciech Wegrzynski>And I, I have a feeling we're gonna touch on it a lot in this episode.

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<v Wojciech Wegrzynski>And I've asked about the summer school because there's a lot of, young fire engineers listening, a lot of, uh, researchers, uh, students graduates, postgraduates, PhD, students posts.

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<v Wojciech Wegrzynski>If you ever wonder if it is worth to go summer school, it is worth it.

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<v Wojciech Wegrzynski>Totally.

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<v Wojciech Wegrzynski>from my experiences with summer schools, it is absolutely amazing way to, to get the knowledge probably the best way, even better than my podcast, I would say  but yeah.

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<v Wojciech Wegrzynski>that.

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<v Wojciech Wegrzynski>Okay.

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<v Wojciech Wegrzynski>Uh, so, let's go back.

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<v Wojciech Wegrzynski>PhD thesis.

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<v Wojciech Wegrzynski>You said you were developing numerical models, and I also know you are involved in development of SAFIR®of the more popular codes in structural engineering.

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<v Wojciech Wegrzynski>So as we venture into the world of, numerical modeling and structural fire engineering, maybe you can tell me like the story, why there was a need for a.

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<v Wojciech Wegrzynski>New codes to be built or just wanted a new ya and, and yeah,  and the home had Italy coast from that.

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<v Wojciech Wegrzynski>Well, that's a good motivation too.

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<v Thomas Gernay>Well, certainly I'm happy , to tell this story because I think, it's a nice one and a timely one.

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<v Thomas Gernay>So, my PGTs is situat.

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<v Thomas Gernay>So we are talking about like 2009, 2012, that range and, The, the tensile membrane action was a big topic.

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<v Thomas Gernay>since I would say one, one decade earlier, right?

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<v Thomas Gernay>It had originated with the observations at Cardington in the 1990s with the Bre and all the research in the UK and professor Wang, professor Bailey, you know, doing those.

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<v Thomas Gernay>Semi, , findings the beginning of two thousands.

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<v Thomas Gernay>And so, it, it became clear that there was really, a need to be able to model, entire structural systems and, the behavior, and not only the structural frame, but that the behavior of concrete and the concrete slabs, became also something that, that matters and that influenced the response.

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<v Wojciech Wegrzynski>So with the tonsil membrane actions, you mean , the way how slabs will respond to the load, how they would carry the forces in the building and how important part they take in like the general structural stability of the building.

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<v Wojciech Wegrzynski>So not just the frame, but also everything that connects the frame.

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<v Thomas Gernay>Exactly.

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<v Thomas Gernay>Yes.

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<v Thomas Gernay>Good point.

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<v Thomas Gernay>So let me backtrack.

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<v Thomas Gernay>Exactly.

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<v Thomas Gernay>So at, the Cardington what was done is that, uh, in the 1990s, the Bre, , they tested entire buildings.

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<v Wojciech Wegrzynski>Yeah.

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<v Thomas Gernay>Subjected to natural fire, right.

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<v Thomas Gernay>To a fire.

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<v Thomas Gernay>And so that was the first or one of the first time, you know, that they really investigated the behavior of the structural system as opposed to testing isolated members in, in furnaces.

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<v Thomas Gernay>And what was observed is that the behavior as a whole was much more favorable and you had this redundancy and those alternate load pass that you could activate.

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<v Thomas Gernay>So you end up with structurally.

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<v Thomas Gernay>Behavior that's more robust than you would predict based on single members' behavior.

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<v Thomas Gernay>For example, you could leave some of the steel beams with no thermal insulation, right?

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<v Thomas Gernay>They would, have exhibit large deflections, but when you get those large deflections in the floors that, go with them, that deflect with them.

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<v Thomas Gernay>, you start activating tension in the reinforcement.

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<v Thomas Gernay>That's embedded in the concrete.

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<v Thomas Gernay>And so this steel reinforcement remains cold.

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<v Thomas Gernay>It's protected, by , the concrete of the slab.

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<v Thomas Gernay>But if it is designed properly, now you can carry the loads, with, this alternate load pass and this, uh, in this deformed shape, which becomes really interesting because it means you have a robust behavior.

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<v Thomas Gernay>That's really embedded in the structure that doesn't require.

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<v Thomas Gernay>Insulation from the thermal election.

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<v Thomas Gernay>so with this realization, they started to be, you know, development of numerical models to try reproduce this behavior and understand it, and then work toward design methods, analytical methods.

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<v Thomas Gernay>but SAFIR was already around and I want , to come back a little bit later on how it had been, uh, developed originally.

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<v Thomas Gernay>Right.

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<v Thomas Gernay>But when I started my PhD, , I would say the behavior of concrete had not been so important before, before 2009.

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<v Thomas Gernay>But, , there started to be all this research on Tenile membrane action and, large scale European research projects.

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<v Thomas Gernay>And we really wanted to have something rub robust and accurate to capture what was happening in those concrete floors.

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<v Thomas Gernay>Uh, when they were undergoing transmembrane action, large displacement heating and cooling and so on.

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<v Thomas Gernay>So that was really the motivation to fill this gap in the.

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<v Thomas Gernay>Computational, modeling tools at that time to have, actual models for concrete in multi Excel, stress date, subjected to heating and cooling and so on.

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<v Wojciech Wegrzynski>Hmm.

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<v Thomas Gernay>so before that it means SAFIR was, was already run and those software as well, of course, to start modeling, you know, structural fire behavior.

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<v Thomas Gernay>And I think that started in the late 1980s and mostly in the 1990s.

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<v Thomas Gernay>The idea was that, of course, to achieve fire safety of the built environment, you have those different layers, of safety that, you want to rely on, right?

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<v Thomas Gernay>So you want prevention, you want, active fire protection and so on, but as a last resort, you really have the structural, uh, fire response.

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<v Thomas Gernay>For quite some times, Al engineers did not really focus much on the structural fire response and fire protection engineers probably had the oversimplified way of thinking about structural fire response and my PG advisor,  Jean-Marc Franssen.

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<v Thomas Gernay>Told me the story of first time he, visited to the us, I think.

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<v Thomas Gernay>And he, he, he got to, he was a young engineer expert in structural fire behavior, but starting, and he got to speak with, somebody working on the fire dynamics, fire protection engineer, and basically they were asking, okay, can you tell me the critical temperature of your structure?

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<v Thomas Gernay>Right.

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<v Thomas Gernay>Because I can do the heat transfer.

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<v Thomas Gernay>I can find the temperature.

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<v Thomas Gernay>So if you tell.

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<v Thomas Gernay>The temperature at which your restric first, you know, we are all set.

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<v Thomas Gernay>We don't need to look more into the structural fire response.

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<v Thomas Gernay>So it was this idea that, it's a purely thermal problem, basically, which is, is not, of course.

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<v Wojciech Wegrzynski>And yeah, but it still is treated like that in many cases, we are drawing isotherms  inside, beams or, even the concept of Charing depth loss of, area of, timber.

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<v Wojciech Wegrzynski>Parts.

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<v Wojciech Wegrzynski>So it still is, in a way considered like a thermal problem.

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<v Wojciech Wegrzynski>And if you think about it, like, let me tap to what you said in Cardington.

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<v Wojciech Wegrzynski>They did for the first time, the full building, but Cardington was like in 1990s and we were doing structural fire engineering for a hundred years back then we've we've been doing it with furnaces.

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<v Wojciech Wegrzynski>In the furnace in essence, unless you have a loaded element, that's a little different when you have

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<v Thomas Gernay>So.

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<v Wojciech Wegrzynski>element and on how you, connect the element to the furnace in terms of what, what the free end is, and then how it can react.

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<v Wojciech Wegrzynski>But in, in a great simplification, the fire test is a thermal test.

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<v Wojciech Wegrzynski>Like essentially.

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<v Wojciech Wegrzynski>Test the thermal behavior, of your system and all the criteria you have are in a way related to the terminal response, especially the insulation and, the capability to, to keep the smoke sealed in inside the compartment, not spread through cracks.

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<v Wojciech Wegrzynski>So.

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<v Wojciech Wegrzynski>We are still , very in the element and, and thermal response paradigm.

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<v Wojciech Wegrzynski>so you want to say that that numerical modeling was a way to break this paradigm or, or escape it in a way.

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<v Thomas Gernay>Absolutely.

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<v Thomas Gernay>Yes, you are right.

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<v Thomas Gernay>We are still relying on this, uh, simplification in most of the case and, , very largely in the field.

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<v Thomas Gernay>And as you say, numerical modeling is actually a way to overcome the simplification and, start investigating the actual, anticipated structural response under.

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<v Thomas Gernay>Thermal demands.

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<v Thomas Gernay>And that is important because we observed that in many case, the thermal approach itself or the element, approach and looking at these ISO terms does not, answer important question or does not really, predict what the NC two behavior is going to be.

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<v Thomas Gernay>So the tenal membrane action was kind of the first, a very remarkable example of that, where you can actually leave.

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<v Thomas Gernay>the temperature go much higher in, some of, in part of your structural frame and still have a very robust behavior.

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<v Thomas Gernay>And so that opens the door to, not only optimization and economic savings in terms of, thermal installation, but also understanding really the safety level of your, building, as well as having a behavior.

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<v Thomas Gernay>That's very robust because this road bearing Capac is really embedded in the structure.

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<v Thomas Gernay>There are many other examples where numerical modeling.

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<v Thomas Gernay>Give you, information that is inaccessible with, uh, element testing and, based on the thermal response.

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<v Thomas Gernay>So I mentioned briefly that I was talking about burnout resistance, uh, during , the summer school in Como.

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<v Thomas Gernay>And actually we can rebound on this.

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<v Thomas Gernay>, so if you start looking at, the structural response to how the different phases of the fire, and you're interested in maintaining stability to full burn out.

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<v Thomas Gernay>Because, uh, structural collapse would not be acceptable because you're concerned about, fire service intervention or, resilience and so on.

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<v Thomas Gernay>then you, you start, uh, having to model what happens during the different phases, including during the cooling and the notion of critical temperature really does not.

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<v Thomas Gernay>Makes more se much sense anymore, because you will have a delayed temperature increase in different parts of the section.

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<v Thomas Gernay>And you have, for example, if we, if we think about a timber section, you might have the Charing that stops, but you still have the heat wave that goes throughout the core of the section, which will lead to additional, reduction of the load bearing capacity.

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<v Thomas Gernay>maybe.

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<v Thomas Gernay>temperatures is lower than the charring temperature, but still higher than what the material can, really support without, being, I would say, damaged or reduced.

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<v Thomas Gernay>So in that sense, you really need this capability to model, structures in fire, because either you want to quantify safety, you want to optimize design.

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<v Thomas Gernay>You want to look at stability to full burnout or many other other situations really.

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<v Wojciech Wegrzynski>Other thing that immediately comes to my mind, I is traveling fires and, , the concept of, of like four hour fire resistance.

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<v Wojciech Wegrzynski>Like there, there is like, no way fire can be in the same place for four hours is like that.

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<v Wojciech Wegrzynski>That would be.

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<v Wojciech Wegrzynski>Insane amount of fuel load in one place.

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<v Wojciech Wegrzynski>Actually you can, um, have fun and try to do the calculations.

00:15:13.825 --> 00:15:19.298
<v Wojciech Wegrzynski>, we were once calculating how much fuel load you would need, to, to create standard condition, on.

00:15:19.952 --> 00:15:23.072
<v Wojciech Wegrzynski>A ceiling of an airport and we came to conclusion.

00:15:23.072 --> 00:15:35.363
<v Wojciech Wegrzynski>It would have to be like literally stacks of, trucks filled with like Ikea furniture on top of each other, reaching almost the ceiling to, to have this four hour fire at this super tall position.

00:15:35.363 --> 00:15:37.133
<v Wojciech Wegrzynski>But now, now back to traveling fires.

00:15:37.341 --> 00:15:46.490
<v Wojciech Wegrzynski>I had an episode with Guillermo Rein about traveling fires and everyone's highly recommended to go back to that one I'll link in the, in the show notes to learn about the method itself.

00:15:46.495 --> 00:15:51.534
<v Wojciech Wegrzynski>, the thing is that there is tons of possible outcomes of the fires.

00:15:51.534 --> 00:15:58.044
<v Wojciech Wegrzynski>There are fires that will travel very quickly, which means they will be very high intensity fires, but they will burn through the fuel very quickly.

00:15:58.615 --> 00:16:04.075
<v Wojciech Wegrzynski>There will be fires that are slow, which burn slowly through the fuel, but they also spread slower.

00:16:05.070 --> 00:16:09.399
<v Wojciech Wegrzynski>And they can go from left to right from right to left from middle out, from out to middle.

00:16:09.758 --> 00:16:13.799
<v Wojciech Wegrzynski>there there's hundreds of, or, or there's limitless amount of, ways.

00:16:13.804 --> 00:16:15.929
<v Wojciech Wegrzynski>How, how a fire can go through the building.

00:16:16.350 --> 00:16:18.659
<v Wojciech Wegrzynski>Even if you're not modeling, if you, if you're just swimming some.

00:16:19.695 --> 00:16:22.884
<v Wojciech Wegrzynski>Saw the fire behavioral as travelling fires, such as simplified model.

00:16:23.274 --> 00:16:28.458
<v Wojciech Wegrzynski>And now, now you end up with hundreds or thousands or tens of thousands of scenarios to investigate.

00:16:28.458 --> 00:16:31.578
<v Wojciech Wegrzynski>And there is absolutely like your fire resistance is just one data point.

00:16:32.418 --> 00:16:32.948
<v Wojciech Wegrzynski>is it.

00:16:33.245 --> 00:16:33.725
<v Wojciech Wegrzynski>that's your

00:16:33.754 --> 00:16:33.995
<v Thomas Gernay>That's.

00:16:34.029 --> 00:16:36.845
<v Wojciech Wegrzynski>point to one time temperature relation.

00:16:37.610 --> 00:16:49.360
<v Wojciech Wegrzynski>In a certain amount of time within this boundary conditions of this particular furnace in this particular laboratory, that is pretty much the answer you have, and you have 10,000 scenarios to go through and compare.

00:16:49.630 --> 00:16:59.081
<v Wojciech Wegrzynski>So no, no way you can relate that, or we try, but it's hard while in numerical modeling, you can probably just test them all or just figure out which are the.

00:17:00.041 --> 00:17:00.130
<v Thomas Gernay>It's.

00:17:00.240 --> 00:17:08.490
<v Wojciech Wegrzynski>you also have experiences in, in this application , or what was it also something you have considered back then when you joined the SAFIR team?

00:17:08.490 --> 00:17:20.069
<v Wojciech Wegrzynski>I guess traveling fires was not the thing because , I think it was just about to begin, in, in this time, but you short, hot or long cold Euro code fires, localized fires were there for sure.

00:17:20.170 --> 00:17:20.920
<v Thomas Gernay>Absolutely.

00:17:21.279 --> 00:17:25.180
<v Thomas Gernay>It's a great point to bring, because I was telling the story of the

00:17:25.394 --> 00:17:25.664
<v Wojciech Wegrzynski>Hmm.

00:17:25.930 --> 00:17:45.904
<v Thomas Gernay>protection engineer, who ask us for, one critical temperature as if it would summarize the response of the structure, but we structural engineers also, uh, may tend to oversimplify and ask, you know, Fire dynamician, uh, to, to provide us with a standard fire curve and think that it'll capture all the possible fire behaviors.

00:17:45.904 --> 00:17:47.704
<v Thomas Gernay>And we can work only with that.

00:17:47.710 --> 00:17:48.964
<v Thomas Gernay>And of course that's not the case.

00:17:48.964 --> 00:17:52.565
<v Thomas Gernay>And as Guillermo is, is shown with, , some papers where he showed that the.

00:17:52.785 --> 00:17:57.164
<v Thomas Gernay>Traveling fires can challenge the structure to, to an extent that is different.

00:17:57.258 --> 00:18:14.250
<v Thomas Gernay>and in some cases more on than, uh, I would say compartment fire conditions, and also the opposite, where there are many situations where once you model The fire behavior based on what we call the physically based fire formally called natural fires.

00:18:14.671 --> 00:18:20.617
<v Thomas Gernay>You find that the conditions may be less on than with the, standard fire or full post flashover fire.

00:18:20.617 --> 00:18:24.723
<v Thomas Gernay>And that also opens, opportunities , for design optimization or.

00:18:25.054 --> 00:18:27.334
<v Thomas Gernay>Even enabling architectural designs.

00:18:27.334 --> 00:18:43.653
<v Thomas Gernay>When, you know, if an architect wants some exposed steel, or exposed timber and, and it really makes sense to look at what are the realistic fire scenarios that could develop in this type of structure and then, , investigate the response of those structure, those fires rather than look.

00:18:43.827 --> 00:18:45.958
<v Thomas Gernay>What we are using in standard furnace test.

00:18:45.958 --> 00:18:46.407
<v Thomas Gernay>Exactly.

00:18:46.768 --> 00:18:47.548
<v Thomas Gernay>So, absolutely.

00:18:48.028 --> 00:18:48.880
<v Thomas Gernay>To your point.

00:18:48.928 --> 00:18:59.538
<v Thomas Gernay>this development of structural fire engineering also, worked alongside developments of fire models for structural engineers and a lot of the.

00:18:59.806 --> 00:19:16.070
<v Thomas Gernay>In the end, impact that it has had on, on practice and where really we could see a value of adopting these analysis was linked not only to a better understanding of the structural fire response, but also, more realistic representation of what, fire scenarios might be.

00:19:16.641 --> 00:19:18.112
<v Thomas Gernay>So that's, I think that that's key.

00:19:19.480 --> 00:19:30.211
<v Thomas Gernay>But I, I think more generally, to your point also, I wanted to compare with what we do in, standardized furnace testing versus what numerical models enable us to do.

00:19:30.211 --> 00:19:36.273
<v Thomas Gernay>So in civil engineering and buildings, we are not dealing with, mass production product, right?

00:19:36.273 --> 00:19:45.854
<v Thomas Gernay>We are not building iPhones or, or cars, uh, where we have the luxury to, build a few specimens that we will test for scale, because we are just building, you know, millions of them.

00:19:46.328 --> 00:19:48.669
<v Thomas Gernay>On the opposite buildings are all unique.

00:19:50.423 --> 00:19:56.721
<v Thomas Gernay>It'll never be an option to build an entire building aside the actual building we want to use and set it on, on fire.

00:19:56.736 --> 00:19:57.185
<v Wojciech Wegrzynski>mm-hmm

00:19:57.230 --> 00:20:08.137
<v Thomas Gernay>what we are doing in a sense is that we are just taking a few components and, and applying a standardized furnace test and extrapolating that it'll inform us on the behavior of the, of the full, building.

00:20:08.567 --> 00:20:18.667
<v Thomas Gernay>As if I would say in a car crash, worse in this test, we are just testing, you know, the, the bumper , and maybe , a few components, and then trying to understand how the car would react in the actual, crush test.

00:20:19.012 --> 00:20:20.953
<v Thomas Gernay>and besides all buildings are different.

00:20:20.959 --> 00:20:23.624
<v Thomas Gernay>So you, you would test the bumper and you would extrapolate that.

00:20:23.703 --> 00:20:29.790
<v Thomas Gernay>Maybe it's, it, it informs you on the, the open, last try on the BME BMW series five the same way.

00:20:29.790 --> 00:20:29.987
<v Thomas Gernay>Right.

00:20:30.423 --> 00:20:34.263
<v Thomas Gernay>so we are never going to do that for ex experimental testing for the building.

00:20:34.263 --> 00:20:45.364
<v Thomas Gernay>So really computational models make a lot of sense because there you can build these, you know, digital twins and challenge them against, lots of, , types of conditions and all those fire scenarios that you mentioned.

00:20:45.614 --> 00:20:47.834
<v Wojciech Wegrzynski>I would put one more thing on, on standard testing.

00:20:48.213 --> 00:20:56.151
<v Wojciech Wegrzynski>Many people don't like this way of talking about standard testing, but, it is in a way, a reality you have to consider standardized.

00:20:57.346 --> 00:21:01.935
<v Wojciech Wegrzynski>in relation to product it is a standardized product testing.

00:21:02.625 --> 00:21:05.175
<v Wojciech Wegrzynski>was never meant to be a test of a building.

00:21:05.175 --> 00:21:13.816
<v Wojciech Wegrzynski>It wasn't because it fits so tightly within the framework of product being certified before it is delivered to the market.

00:21:14.236 --> 00:21:18.073
<v Wojciech Wegrzynski>So the market understands the, that stands the core characteristics of the product.

00:21:18.673 --> 00:21:23.425
<v Wojciech Wegrzynski>And that's exactly the need that, fire testing in laboratory, caters for.

00:21:23.851 --> 00:21:30.023
<v Wojciech Wegrzynski>And therefore, because we have this as a standard product testing, the.

00:21:30.439 --> 00:21:35.409
<v Wojciech Wegrzynski>Manufacturers use this as a ranking tool or, know, it's a way to compete.

00:21:35.409 --> 00:21:37.328
<v Wojciech Wegrzynski>Ah, my product has this classification.

00:21:37.328 --> 00:21:40.148
<v Wojciech Wegrzynski>Yours has other ones, so mine is better.

00:21:41.148 --> 00:21:45.729
<v Wojciech Wegrzynski>It, gives you a fairly easy way to, overlook the market.

00:21:45.759 --> 00:21:51.128
<v Wojciech Wegrzynski>Others, like only one product that has this specific barter and every other is where.

00:21:51.128 --> 00:21:53.469
<v Wojciech Wegrzynski>So, so I lose this one and it also.

00:21:53.794 --> 00:22:04.387
<v Wojciech Wegrzynski>It's a very attractive way for nonspecialist stakeholders, to, to put a product because they, they have no idea, but the code says this product of this characteristic is just enough for your building.

00:22:04.387 --> 00:22:08.795
<v Wojciech Wegrzynski>So, so like this is a whole framework fit around.

00:22:08.885 --> 00:22:15.276
<v Wojciech Wegrzynski>Delivering products to market that cater to specific needs and can be distinguished by the characteristics.

00:22:15.605 --> 00:22:22.195
<v Wojciech Wegrzynski>Whereas a building does not have a, a single, uh, response, fire, fire resistance characteristic.

00:22:22.502 --> 00:22:27.363
<v Wojciech Wegrzynski>uh, like you said, it can burn and, and collapse in probably thousands of ways.

00:22:28.343 --> 00:22:30.728
<v Wojciech Wegrzynski>of them will be different, very specific.

00:22:30.948 --> 00:22:43.490
<v Wojciech Wegrzynski>And the job of structural engineer like you is, to make sure that in a probable scenarios, it, does, not collapse or, or that, um, maybe even more that.

00:22:43.932 --> 00:22:45.732
<v Wojciech Wegrzynski>There is no disproportionate collapse.

00:22:45.732 --> 00:22:47.113
<v Wojciech Wegrzynski>Like very small fire.

00:22:47.113 --> 00:22:53.563
<v Wojciech Wegrzynski>Doesn't collapse it because if you, if a meter strikes your building, then it's not gonna probably survive.

00:22:53.563 --> 00:22:54.772
<v Wojciech Wegrzynski>So, here, is this.

00:22:54.857 --> 00:22:59.538
<v Wojciech Wegrzynski>Fork between the product market and the building market.

00:22:59.928 --> 00:23:01.817
<v Wojciech Wegrzynski>It's just in ice of many people.

00:23:01.817 --> 00:23:04.917
<v Wojciech Wegrzynski>It's the same market where it not necessarily is.

00:23:05.127 --> 00:23:11.800
<v Wojciech Wegrzynski>However, I, I still find but you still don't do structural engineering like that for every single building.

00:23:11.800 --> 00:23:16.903
<v Wojciech Wegrzynski>Right there, there, there are like, cake type buildings that you just take from the book,

00:23:17.534 --> 00:23:18.284
<v Thomas Gernay>Absolutely.

00:23:18.284 --> 00:23:19.064
<v Thomas Gernay>And so, yeah.

00:23:19.213 --> 00:23:21.523
<v Thomas Gernay>Also let me make a few things clear.

00:23:21.673 --> 00:23:27.733
<v Thomas Gernay>first of all, I mean, standardized for testing is tremendously important and it has delivered the baseline of safety.

00:23:27.733 --> 00:23:28.034
<v Thomas Gernay>Right?

00:23:28.034 --> 00:23:30.528
<v Thomas Gernay>It's been a great answer , to a true problem.

00:23:30.528 --> 00:23:32.929
<v Thomas Gernay>At the beginning of the 20th century, it has.

00:23:33.453 --> 00:23:35.554
<v Thomas Gernay>Product amazing benefits.

00:23:35.943 --> 00:23:45.183
<v Thomas Gernay>And even for us, you know, working on computational modeling, experimental testing is absolutely crucial component to validate our models.

00:23:45.183 --> 00:23:50.586
<v Thomas Gernay>Whenever new material are developed, we need the data, we cannot just, extrapolate material models.

00:23:50.747 --> 00:23:52.517
<v Thomas Gernay>We have to have those, those data points.

00:23:52.787 --> 00:23:53.866
<v Thomas Gernay>So all this absolutely.

00:23:53.866 --> 00:23:54.017
<v Thomas Gernay>And so.

00:23:55.231 --> 00:23:56.162
<v Thomas Gernay>As we speak.

00:23:56.211 --> 00:24:01.092
<v Thomas Gernay>, I would say push on the limitations to make clear, why we do what we do and what's the value added.

00:24:01.092 --> 00:24:04.153
<v Thomas Gernay>But, it doesn't mean that there are lots of, rational.

00:24:04.213 --> 00:24:19.834
<v Thomas Gernay>So for continuing doing those, those standardized tests, but I mean, I agree with what you said, it's really in, going further than, certifying these products and understanding or hating, the behavior of, of these, you know, beams and columns and doors and so on.

00:24:20.609 --> 00:24:22.049
<v Thomas Gernay>How do we scale that up?

00:24:22.170 --> 00:24:28.259
<v Thomas Gernay>And how do we re interrogate the true safety level of the assembly of the system?

00:24:28.559 --> 00:24:41.069
<v Thomas Gernay>Once we build the building out of these components, and that is something that we don't have the luxury to look at true full scale experimental testing, because in civil engineering, we are building unique.

00:24:41.875 --> 00:24:42.444
<v Thomas Gernay>Objects.

00:24:42.444 --> 00:24:42.684
<v Thomas Gernay>Right.

00:24:43.045 --> 00:24:49.259
<v Thomas Gernay>So, I argue that computational modeling is really the tool to, bridge this gap and to go to that, , higher level.

00:24:49.528 --> 00:24:53.872
<v Thomas Gernay>And as you said, there are many ways that, a fire can challenge a structure.

00:24:54.642 --> 00:25:03.152
<v Thomas Gernay>And we need to make sure that what we are building is, robust when it's in, I mean, the true conditions and subjected to physically based fire.

00:25:03.632 --> 00:25:17.731
<v Thomas Gernay>And when we are looking at performance subjectives that might go beyond, standardized rating or one or two standard for resistance, but we might need to demonstrate survival to full burnout or, the fact that the damage remains localized.

00:25:17.731 --> 00:25:18.932
<v Thomas Gernay>And we don't have this kind of.

00:25:19.241 --> 00:25:21.192
<v Thomas Gernay>Progressive collapses you

00:25:23.515 --> 00:25:28.832
<v . Wojciech Wegrzynski>And, in the interface between fire testing and, , full scale behavior.

00:25:29.402 --> 00:25:30.541
<v . Wojciech Wegrzynski>You use fire testing

00:25:30.541 --> 00:25:30.884
<v Thomas Gernay>were, uh, referring to and so on.

00:25:30.884 --> 00:25:30.885
<v Thomas Gernay>Yes.

00:25:30.885 --> 00:25:30.886
<v Thomas Gernay>And.

00:25:31.652 --> 00:25:38.301
<v Wojciech Wegrzynski>and, , as a way to obtain,, data on, on the materials on structural behavior.

00:25:38.821 --> 00:25:42.896
<v Wojciech Wegrzynski>But in the end, , when you go into numerical modeling, of a building.

00:25:43.076 --> 00:25:49.826
<v Wojciech Wegrzynski>If we can jump in into that part, you still like using the standard curve as your boundary condition?

00:25:49.826 --> 00:25:58.230
<v Wojciech Wegrzynski>Or would you go like with your code, your localized fire, how do you like you, you have your properties of your materials and stuff.

00:25:58.230 --> 00:26:01.859
<v Wojciech Wegrzynski>How do you define fire in, in structural for engineering then?

00:26:02.470 --> 00:26:05.253
<v Wojciech Wegrzynski>.

00:26:02.470 --> 00:26:08.334
<v Wojciech Wegrzynski>Thomas Gernay: So when we, for, , predicting the behavioral infrastructure and fire.

00:26:08.334 --> 00:26:10.433
<v Wojciech Wegrzynski>And as you said before, it's not for.

00:26:11.078 --> 00:26:19.633
<v Wojciech Wegrzynski>Every, small building or every case, but when we do so usually we frame it in, the context of performance based, fire design, right?

00:26:19.637 --> 00:26:25.633
<v Wojciech Wegrzynski>So it means that we start by, uh, setting up objectives, performance objectives for design.

00:26:25.633 --> 00:26:27.313
<v Wojciech Wegrzynski>So explicitly we have to Mm.

00:26:27.462 --> 00:26:33.398
<v Thomas Gernay>define what we are trying to achieve or what we want, what conditions we want, the, to survive , and.

00:26:34.614 --> 00:26:40.347
<v Thomas Gernay>Failure means and what, a successful design is, because that will be different, for whole structures.

00:26:40.827 --> 00:26:49.493
<v Thomas Gernay>As I said before, for some, we may want to demonstrate survival to full burn out of the fires and for those a certain duration of stability or.

00:26:50.108 --> 00:26:51.608
<v Thomas Gernay>Yet other objectives.

00:26:51.999 --> 00:26:56.078
<v Thomas Gernay>So then at the, the second step, we will work on design fires.

00:26:56.138 --> 00:27:04.068
<v Thomas Gernay>And in this context of performance based fire design, usually we don't rely on the standard, fire curve, which really has another purpose.

00:27:04.368 --> 00:27:15.980
<v Thomas Gernay>So once we are going with modeling, we are interested in, Trying to predict realistic or physically based fires that that would develop given the conditions and what we know of the inputs for the building.

00:27:16.461 --> 00:27:28.384
<v Thomas Gernay>And so we might have to check both post slash over fires and localized slash traveling fires, depending on the geometry of the compartment, ventilation conditions, the fuel and.

00:27:28.978 --> 00:27:42.084
<v Thomas Gernay>it is not enough to consider one design fire because there are so, so many uncertainties involved, a robust performance based design will rely on, uh, a series of design fires and, and look at the effects of variation of these inputs.

00:27:42.743 --> 00:27:46.284
<v Thomas Gernay>Usually it's good practice to, in any case, check a localized.

00:27:47.038 --> 00:27:51.388
<v Thomas Gernay>That might be very close to a column, for example, which will always occur at the beginning, right.

00:27:51.388 --> 00:27:58.048
<v Thomas Gernay>At the early stage of the fire and then the, the full growth and development of that fire, possibly transitioning to flashover.

00:27:58.563 --> 00:28:03.123
<v Thomas Gernay>we know of course, for example, ventilation assumptions will have a big impact also.

00:28:03.123 --> 00:28:04.449
<v Thomas Gernay>So, there is some guidance.

00:28:05.189 --> 00:28:07.506
<v Thomas Gernay>to look at when, windows will, break.

00:28:07.746 --> 00:28:15.239
<v Thomas Gernay>And so how, you can have your, ventilation condition suddenly change when the gas temperature reaches a certain value, these type of things.

00:28:15.929 --> 00:28:19.229
<v Thomas Gernay>Um, so first performance objectives, second design fires.

00:28:19.233 --> 00:28:22.982
<v Thomas Gernay>And then we go with, the tur marts to response of, of the structure itself.

00:28:23.343 --> 00:28:23.643
<v Thomas Gernay>Yes.

00:28:23.712 --> 00:28:26.952
<v Wojciech Wegrzynski>you have the assumptions, but you don't have them fire modeling yet.

00:28:27.282 --> 00:28:32.249
<v Wojciech Wegrzynski>So you would go with like some simple, hand calculations, the model.

00:28:32.278 --> 00:28:35.608
<v Wojciech Wegrzynski>I don't think CFD, but because I think that would be very rare.

00:28:35.969 --> 00:28:38.338
<v Wojciech Wegrzynski>So how you go from assumptions to thermal?

00:28:39.476 --> 00:28:40.135
<v Thomas Gernay>You're right.

00:28:40.195 --> 00:28:46.165
<v Thomas Gernay>I didn't mention it, but no, we have access to the full suite of tools there so we can do.

00:28:46.233 --> 00:28:52.354
<v Thomas Gernay>Analytical methods, kind of OC code barometric fire that we have commonly used.

00:28:52.354 --> 00:28:55.324
<v Thomas Gernay>For example, in probabilistic, risk assessment analysis.

00:28:55.324 --> 00:29:01.144
<v Thomas Gernay>We want a lot of scenarios and really look at this variability of conditions for localized fire.

00:29:01.384 --> 00:29:01.743
<v Thomas Gernay>Yes,

00:29:01.953 --> 00:29:13.433
<v Wojciech Wegrzynski>go traveling fire, like we've mentioned before, where you would have a plethora of scenarios, which are like, pregenerated for your geometry with a very simple model of different complexity, depending which you use.

00:29:13.463 --> 00:29:13.673
<v Wojciech Wegrzynski>Yeah.

00:29:14.003 --> 00:29:14.223
<v Wojciech Wegrzynski>And.

00:29:14.304 --> 00:29:14.844
<v Thomas Gernay>Absolutely.

00:29:14.844 --> 00:29:19.854
<v Thomas Gernay>So analytical model for post flashover or traveling fire or localized fire.

00:29:19.854 --> 00:29:23.213
<v Thomas Gernay>So in the Euro code, , we are usually relying on models in the Euro code.

00:29:23.574 --> 00:29:36.691
<v Thomas Gernay>you have Hasemi you have, uh, Heskestad you have now locafi will be included in the next, version of Euro code, which is a solid flame model to capture the, heat, radiation to a member that is outside of the fire.

00:29:37.215 --> 00:29:46.949
<v Thomas Gernay>we have, sort of traveling fire models that you mentioned also with some very elegant and, and relatively simple solutions, but we also use FDS and, actually one of the.

00:29:48.344 --> 00:29:59.020
<v Thomas Gernay>Not so recent anymore, but relatively recent development in severe was to facilitate the transfer between, output data from FDS and the thermal structural analysis.

00:29:59.441 --> 00:30:04.961
<v Thomas Gernay>So usually there are two techniques that we would use, to couple, CFD simulation.

00:30:04.961 --> 00:30:10.624
<v Thomas Gernay>And I'm talking about FDS interchangeably because that's really the most common, with, uh, FVM analysis.

00:30:11.163 --> 00:30:16.263
<v Thomas Gernay>We can use the concept of about surface temperature developed by, by Wickstrom and we've done that.

00:30:16.263 --> 00:30:18.604
<v Thomas Gernay>So we have all those sensors around or switch.

00:30:19.233 --> 00:30:24.243
<v Thomas Gernay>We need to make sure we have enough of them to capture thermal gradients to capture, shadow effect and so on.

00:30:24.314 --> 00:30:24.433
<v Wojciech Wegrzynski>Hmm.

00:30:24.723 --> 00:30:26.854
<v Thomas Gernay>And, uh, but if, when we are looking at.

00:30:27.499 --> 00:30:29.358
<v Thomas Gernay>Modeling a larger structure.

00:30:29.358 --> 00:30:37.913
<v Thomas Gernay>For example, we've used in open car park simulation and these type of things where we have lots of structural members and, we would need a lot of, of sensors.

00:30:38.333 --> 00:30:42.888
<v Thomas Gernay>We have also, the option to use, automatic, interface file.

00:30:43.398 --> 00:30:46.288
<v Thomas Gernay>So, it was developed with the developers of FDS.

00:30:46.288 --> 00:30:52.618
<v Thomas Gernay>Actually, we can ask FDS to write a transfer file as a output of the simulation that will.

00:30:53.019 --> 00:30:59.205
<v Thomas Gernay>Output the, the gas, temperature and radiant intensity along lots of directions, in space.

00:31:00.137 --> 00:31:13.397
<v Thomas Gernay>I mean, special coordinates in a domain that we define and SAFIR can read this transfer file and, uh, use that as input thermal boundary conditions for the heat transfer analysis in the sections.

00:31:13.428 --> 00:31:16.218
<v Thomas Gernay>And that is the advantage that it's automatized.

00:31:16.248 --> 00:31:22.488
<v Thomas Gernay>So it's well suited when you have a big structure and, uh, it captures the shadow effect.

00:31:22.488 --> 00:31:26.167
<v Thomas Gernay>It, it sees the view angles and, and everything to capture radiation, , appropriately.

00:31:26.303 --> 00:31:27.073
<v Wojciech Wegrzynski>This is brilliant.

00:31:27.108 --> 00:31:28.368
<v Wojciech Wegrzynski>I didn't know about that.

00:31:28.368 --> 00:31:32.942
<v Wojciech Wegrzynski>I actually, uh, I'm like in ANSYS ecosystem, so, I know.

00:31:33.117 --> 00:31:37.290
<v Wojciech Wegrzynski>A bit on FDS because, my I have to follow

00:31:37.520 --> 00:31:37.760
<v Thomas Gernay>All of

00:31:37.891 --> 00:31:42.048
<v Wojciech Wegrzynski>but I'm not like everyday user of, FDS outside of scientific research.

00:31:42.498 --> 00:31:45.739
<v Wojciech Wegrzynski>And this, sounds like, really like, Really nice development sometime ago.

00:31:45.739 --> 00:31:45.949
<v Wojciech Wegrzynski>I was

00:31:45.963 --> 00:31:46.054
<v Thomas Gernay>that.

00:31:46.278 --> 00:32:05.528
<v Wojciech Wegrzynski>like, what has changed in like last 10 years when I work in this field and not that much has changed, but this is something like really a huge quality of life, improvement that really allows you for less, uh, connection between your fluid and structure That that's very interesting.

00:32:05.888 --> 00:32:07.469
<v Wojciech Wegrzynski>And have you tried anything.

00:32:08.256 --> 00:32:15.036
<v Wojciech Wegrzynski>in the, in, I know in ANSYS ecosystem, I, I have not have not mastered this functionality yet.

00:32:15.455 --> 00:32:20.286
<v Wojciech Wegrzynski>One of my colleagues in the office is playing, but we have like, two-way coupled interactions.

00:32:20.290 --> 00:32:27.903
<v Wojciech Wegrzynski>So if like, the structure, let's say you have a steel sheet roof, and if the roof fails, you have a.

00:32:28.617 --> 00:32:33.087
<v Wojciech Wegrzynski>And that hole is then transferred from my structural model to fluid model.

00:32:33.087 --> 00:32:40.044
<v Wojciech Wegrzynski>So the fluid model in, in incorporates the, the way how, uh, this hole would, change the flow fields.

00:32:40.361 --> 00:32:46.317
<v Wojciech Wegrzynski>but I guess that that's quite complicated, probably difficult, especially if you have, solvers, not within the one ecosystem.

00:32:46.684 --> 00:32:47.932
<v Thomas Gernay>It is complicated.

00:32:47.992 --> 00:32:53.393
<v Thomas Gernay>That's something we, we have not addressed yet, but it is relevant for certain applications.

00:32:53.393 --> 00:32:54.383
<v Thomas Gernay>You mentioned an example.

00:32:54.383 --> 00:33:00.032
<v Thomas Gernay>There are, of course other example where this, Two way feedback or two way coupling, makes sense.

00:33:00.272 --> 00:33:18.009
<v Thomas Gernay>I would say fundamentally, when I'm describing this, these developments, it really comes from a, a realization our behalf and people working in structural fire engineering, that a lot of the advances and the gaps were at the intersection of the disciplines as is often the case in, you know, in engineering and science.

00:33:18.009 --> 00:33:18.368
<v Thomas Gernay>So.

00:33:18.969 --> 00:33:28.854
<v Thomas Gernay>I told you earlier, the story of the fire protection engineers, who asked for the critical temperature and the, the structural engineer who asked for the, the standup, Fire resistance or fire curve.

00:33:29.273 --> 00:33:43.327
<v Thomas Gernay>So, we saw that value was in, connecting those two words and making it easier in terms of the numerical modeling ecosystem to bridge and couple the advanced fire models with the advanced,, structural simulations.

00:33:43.567 --> 00:33:50.738
<v Thomas Gernay>So we are putting a lot of efforts on these, and right now we have all these options for the one way, coupling from the fire to the structure.

00:33:51.067 --> 00:33:53.258
<v Thomas Gernay>What you describe is, is very interesting.

00:33:53.364 --> 00:33:59.691
<v Thomas Gernay>future development that can possibly, you know, is making even more important.

00:33:59.698 --> 00:34:10.548
<v Thomas Gernay>and I would say timely now with, the use of compostable building materials and this tension between sustainability and, fire safety that, that we are observing.

00:34:10.548 --> 00:34:31.115
<v Thomas Gernay>And professor Luke Biby had the, had the great, uh, Position paper on this, the fact that we are innovating fast to address the climate emergency, and we are doing those changes in the way we build structure and we use material and, and we have, the example with facets, the example with mass timber and so on, and they are implications for, fire safety.

00:34:31.146 --> 00:34:34.085
<v Thomas Gernay>And we need to make sure while we address this very important.

00:34:34.423 --> 00:34:35.563
<v Thomas Gernay>Momentous, right.

00:34:35.893 --> 00:34:40.753
<v Thomas Gernay>A challenge of climate crisis that also, it's not at the expense of public safety.

00:34:41.264 --> 00:34:46.364
<v Thomas Gernay>And I think computation modelling is a tremendous hole to play there because innovation goes so fast.

00:34:46.364 --> 00:34:54.550
<v Thomas Gernay>We need to predict what, the implications are going to be and what challenges it poses for fire, behavior, including structural fire behavior.

00:34:55.306 --> 00:35:07.989
<v Thomas Gernay>But in some cases, there might be a question of two-way coupling that you were describing it's abuse, that exposed timber is going to fuel the fire and affect the fire dynamic as well as having, you know, the load bearing function that it has.

00:35:07.989 --> 00:35:08.469
<v Thomas Gernay>And so on.

00:35:08.858 --> 00:35:15.208
<v Thomas Gernay>And there are, there are other examples where, you might have the switch response affect , the biodynamics, and thermal environment.

00:35:15.867 --> 00:35:18.117
<v Thomas Gernay>It's also important in, um, other.

00:35:18.452 --> 00:35:33.498
<v Thomas Gernay>Questions, for example, I would say compartmentation issues and even, , failure of non load bearing, uh, walls and compartment boundaries, that this is also something that right now we cannot really predict with those computational models, but.

00:35:34.963 --> 00:35:49.418
<v Thomas Gernay>As we were talking about traveling fire, it might be interesting to have the capability to, predict if due to large deflections of the road bearing structure, it might damage some, non road bearing wards, and then the fire can travel to the next component.

00:35:49.418 --> 00:35:53.371
<v Thomas Gernay>So there are still lots of, very interesting and, uh, challenging questions to explore.

00:35:53.543 --> 00:36:03.157
<v Wojciech Wegrzynski>For me, one of the most interesting is the behavior of, of glazing because it's something that, we are very highly reliant on in our.

00:36:04.340 --> 00:36:17.300
<v Wojciech Wegrzynski>and, and not always, we're very explicit about it because, uh, we just assume an opening factor, which is usually related to the glazed area, assuming that it's gonna fall off, which not necessarily is the case.

00:36:17.300 --> 00:36:20.818
<v Wojciech Wegrzynski>And, uh, modern glazing is, is showing more changes.

00:36:20.833 --> 00:36:24.672
<v Wojciech Wegrzynski>Did you have any solutions for that in, in SAFIR like special models or, or something?

00:36:25.572 --> 00:36:30.965
<v Thomas Gernay>We don't explicitly model, usually the glazing, we don't, we don't model, non road bearing, members.

00:36:30.965 --> 00:36:33.306
<v Thomas Gernay>So tradition is a very practical answer.

00:36:33.306 --> 00:36:33.425
<v Thomas Gernay>Sorry.

00:36:33.630 --> 00:36:34.351
<v Wojciech Wegrzynski>Sorry.

00:36:34.351 --> 00:36:42.081
<v Wojciech Wegrzynski>So that goes back to the, your assumptions and , the thermal model that is run before , the thermal structural model.

00:36:42.260 --> 00:36:42.471
<v Wojciech Wegrzynski>Yeah.

00:36:42.905 --> 00:36:43.565
<v Thomas Gernay>That's right.

00:36:43.626 --> 00:36:51.070
<v Thomas Gernay>So, a practical answer is that there, there is, , a guidance in the Luxembourg annex to the Eurocode, which is.

00:36:51.659 --> 00:36:57.306
<v Thomas Gernay>Just pragmatic, way of approaching this question of, glazing and, changing ventilation.

00:36:57.606 --> 00:37:09.365
<v Thomas Gernay>So in the Luxem book annex, they give a temperature of the gas at which a certain ratio of the windows get broken, depending on the type, if it's simple, double, triple glazing or reinforced glazing.

00:37:10.521 --> 00:37:12.440
<v Thomas Gernay>They also prescribe doing a few scenarios.

00:37:12.440 --> 00:37:20.391
<v Thomas Gernay>So for example, they would say we're in a scenario where 90% of your windows are opened from the start and then another scenario where they are closed.

00:37:20.751 --> 00:37:21.753
<v Thomas Gernay>But I don't know.

00:37:21.753 --> 00:37:36.543
<v Thomas Gernay>I remember 30% that opens when the gas go to 200 degrees, C and then 90% when it goes to 300 degrees C it just gives you a framework such that you, first of all, you check different scenarios because we know the fire.

00:37:36.617 --> 00:37:40.081
<v Thomas Gernay>conditions, the demand will be very different depending on those inputs.

00:37:40.320 --> 00:37:42.570
<v Thomas Gernay>So again, one design fire is not enough.

00:37:42.914 --> 00:37:47.737
<v Thomas Gernay>and also while you have some guidance, everybody does, you know, the same and, and it's, it is linked.

00:37:47.742 --> 00:37:52.983
<v Thomas Gernay>It is correlated to, failure temperature of glazing based on thermal gradients on the, on the surface.

00:37:53.403 --> 00:37:56.764
<v Thomas Gernay>But it's not a detailed modeling of the, of, of the class behavior.

00:37:56.768 --> 00:37:58.365
<v Wojciech Wegrzynski>for this robust, answer this.

00:37:59.175 --> 00:38:01.076
<v Wojciech Wegrzynski>was also not aware of the Luxemburg annext.

00:38:01.096 --> 00:38:06.853
<v Wojciech Wegrzynski>I, I need to check that out because it, it is something that I'm recently very interested at.

00:38:07.213 --> 00:38:11.862
<v Wojciech Wegrzynski>I'm also, uh, about to organize the nice guest on, on the glazing in, in the podcaster.

00:38:11.862 --> 00:38:13.938
<v Wojciech Wegrzynski>There's also an episode to look for.

00:38:14.423 --> 00:38:17.213
<v Wojciech Wegrzynski>now I wanted to ask you, like, where is it going?

00:38:17.594 --> 00:38:21.918
<v Wojciech Wegrzynski>Is there any particular direction that, structural FSC modeling is

00:38:22.083 --> 00:38:22.202
<v Thomas Gernay>How you

00:38:22.458 --> 00:38:24.077
<v Wojciech Wegrzynski>or SAFIR is, is heading?

00:38:24.467 --> 00:38:26.057
<v Wojciech Wegrzynski>Like how, how do you guys

00:38:26.193 --> 00:38:26.643
<v Thomas Gernay>guys more

00:38:26.782 --> 00:38:27.768
<v Wojciech Wegrzynski>the future?

00:38:28.038 --> 00:38:39.757
<v Wojciech Wegrzynski>Will it be like more simulations, more answers more probabilistic approach, or maybe rather, into root of optimization and trying to find.

00:38:40.688 --> 00:38:44.378
<v Wojciech Wegrzynski>The cheapest, non collapsible structure you can build

00:38:44.543 --> 00:38:44.902
<v Thomas Gernay>you can.,

00:38:45.438 --> 00:38:46.157
<v Wojciech Wegrzynski>your boundaries.

00:38:46.367 --> 00:38:50.927
<v Wojciech Wegrzynski>I wonder what, what's the hot topic now in the world of structural fire engineers.

00:38:51.391 --> 00:38:52.978
<v Thomas Gernay>that's great question.

00:38:52.978 --> 00:38:58.141
<v Thomas Gernay>Of course, we are working really on a range of problems and always trying to move that forward.

00:38:58.380 --> 00:39:09.963
<v Thomas Gernay>I think high level I'm, I'm really convinced that numerical modeling is, is a key enabler of, you know, everything we do in, in, in civil engineering to engineering is, we want.

00:39:10.077 --> 00:39:11.641
<v Thomas Gernay>Provide two things.

00:39:11.641 --> 00:39:15.931
<v Thomas Gernay>We want to provide the tools, really the ecosystem that people can go.

00:39:15.931 --> 00:39:22.351
<v Thomas Gernay>And it's, it's robust, it's validated it's state of the art and you can run those software to predict the response.

00:39:22.501 --> 00:39:25.585
<v Thomas Gernay>And we also work , on the framework, which is to understand how.

00:39:26.201 --> 00:39:38.603
<v Thomas Gernay>Computational modeling, can support and is linked to performance based design to probabilistic risk assessment and these type of, very important approaches that are used in not only fire safety engineering, but in general in structural design.

00:39:38.934 --> 00:39:39.233
<v Thomas Gernay>So.

00:39:39.639 --> 00:39:46.748
<v Thomas Gernay>In the future, what, what we are really focusing on now, I would say maybe, , three things that I, I want to highlight.

00:39:47.228 --> 00:39:59.206
<v Thomas Gernay>The first one is that there are always new, , materials and innovations that come on the market that are considered and understanding the fire safety implications of these are really, critical and.

00:40:00.396 --> 00:40:05.239
<v Thomas Gernay>Because if we don't, it can, hinder the implementation of these in the market.

00:40:05.239 --> 00:40:14.438
<v Thomas Gernay>So, I mean, we have, you know, amazing people doing developments to, bring these new materials to, uh, maybe be more, environmentally friendly, but we, we need to be able to, to apply them.

00:40:14.438 --> 00:40:17.362
<v Thomas Gernay>So we need to understand, What the implication is for fire safety.

00:40:17.693 --> 00:40:23.112
<v Thomas Gernay>And so that, implies being able to model the thermal mechanical properties, the behavior of those materials.

00:40:23.532 --> 00:40:28.362
<v Thomas Gernay>In some cases, when it's, combustible material, it is, I mean, other challenges as well.

00:40:28.572 --> 00:40:33.762
<v Thomas Gernay>And then how do we model the, these in structural system and, building simulations, right?

00:40:33.762 --> 00:40:36.373
<v Thomas Gernay>So that's, that's really the fir the first point.

00:40:36.777 --> 00:40:37.809
<v Thomas Gernay>the second one is.

00:40:38.313 --> 00:40:40.983
<v Thomas Gernay>As I was just hitting at, working on the frameworks.

00:40:41.253 --> 00:40:51.164
<v Thomas Gernay>So I'm very interested in performance based fire design, which means how do we go, about this, this process of defining performance objectives.

00:40:51.164 --> 00:40:52.724
<v Thomas Gernay>So already lots of questions.

00:40:52.724 --> 00:40:53.951
<v Thomas Gernay>What is, appropriate?

00:40:54.365 --> 00:40:58.983
<v Thomas Gernay>Performance level, what kind of, targets reliability should we strive for?

00:40:58.983 --> 00:41:03.793
<v Thomas Gernay>What, are the implications of looking at resilience of the built environment against fire, multi hazard?

00:41:03.793 --> 00:41:09.222
<v Thomas Gernay>So lots of questions they already, then once we have the performance objective, we have to define the design fires.

00:41:09.228 --> 00:41:10.302
<v Thomas Gernay>And we've talked about that.

00:41:10.307 --> 00:41:15.943
<v Thomas Gernay>There are also lots of scenarios and how, uh, do we know which one to select and then how do we make.

00:41:16.478 --> 00:41:21.101
<v Thomas Gernay>Easy to, develop these and interface them with the SIM with the Al simulation.

00:41:21.311 --> 00:41:31.797
<v Wojciech Wegrzynski>I love how the challenge is like at the philosophical level, not necessarily related to like, transferring loads or, or modeling, uh, non-linear thermal behavior materials.

00:41:31.797 --> 00:41:35.007
<v Wojciech Wegrzynski>No, we really have to sort out the scenarios and objectives.

00:41:35.472 --> 00:41:36.793
<v Wojciech Wegrzynski>This is the number

00:41:37.108 --> 00:41:37.197
<v Thomas Gernay>Well,

00:41:37.487 --> 00:41:38.503
<v Wojciech Wegrzynski>like the need.

00:41:38.503 --> 00:41:44.018
<v Wojciech Wegrzynski>I, I really love how you positioned it because it echos so well with so much that has been said in the, in the podcast.

00:41:44.018 --> 00:41:46.088
<v Wojciech Wegrzynski>I absolutely love it, but sorry for interrupting.

00:41:46.088 --> 00:41:46.898
<v Wojciech Wegrzynski>You continue this.

00:41:47.153 --> 00:41:48.503
<v Thomas Gernay>No, no, thanks APRI.

00:41:48.503 --> 00:41:49.673
<v Thomas Gernay>But yeah, I think it's key.

00:41:49.853 --> 00:41:50.304
<v Thomas Gernay>Absolutely.

00:41:50.304 --> 00:41:52.344
<v Thomas Gernay>It's both the tools and the framework.

00:41:52.349 --> 00:41:53.423
<v Thomas Gernay>How do we use the tool?

00:41:53.423 --> 00:41:57.324
<v Thomas Gernay>We want to think very hard about that as well because providing the tools is not enough.

00:41:57.713 --> 00:41:58.974
<v Thomas Gernay>We want it to be robust.

00:41:58.974 --> 00:42:03.284
<v Thomas Gernay>We want it to, make sense in terms of the risk assessment and the performance and so on.

00:42:03.284 --> 00:42:07.784
<v Thomas Gernay>So working on the design fire, still on, in my performance base for design, right.

00:42:07.784 --> 00:42:09.704
<v Thomas Gernay>And then on the structural modeling.

00:42:10.003 --> 00:42:10.224
<v Wojciech Wegrzynski>Mm.

00:42:10.583 --> 00:42:11.634
<v Thomas Gernay>There is a lot we can do.

00:42:11.634 --> 00:42:18.740
<v Thomas Gernay>We've worked a lot, this last decade and before, but there are, there, there are still things we cannot do, modeling a CLT floor.

00:42:18.784 --> 00:42:21.038
<v Thomas Gernay>we don't really have the element to do that, right now.

00:42:21.038 --> 00:42:24.038
<v Thomas Gernay>So, but it's, it's used people build buildings with that.

00:42:24.038 --> 00:42:28.443
<v Thomas Gernay>So if we want to model this structural system, That will be something more practical.

00:42:28.443 --> 00:42:31.179
<v Thomas Gernay>We, we need a PhD to look at a PhD student.

00:42:31.179 --> 00:42:39.818
<v Thomas Gernay>I made to look for three, four years at how do we develop the type of, shell elements and the material model and, and C on for this or Tropic behavior.

00:42:39.824 --> 00:42:42.608
<v Thomas Gernay>So they are also this kind of questions of course, that we are working on.

00:42:43.268 --> 00:42:43.978
<v Thomas Gernay>And so first was.

00:42:44.083 --> 00:42:49.634
<v Thomas Gernay>You know, new materials, enabling that S on the framework, the per performance based design, also probabilistic.

00:42:50.023 --> 00:43:06.277
<v Thomas Gernay>I've not talked that much about it, but I've worked a lot with some incredibly smart colleagues, just Ruben van Coile and Danny Hopkin, whom had here Negar Elhami-Khorasni a good friend and amazing researcher from university of Buffalo and others.

00:43:06.277 --> 00:43:08.717
<v Thomas Gernay>And together we, we teamed up because , it's a very.

00:43:08.987 --> 00:43:21.108
<v Thomas Gernay>Big challenge to move, structural fire engineering, into the probability risk assessment framework and make it, very, consistent in terms of how we think about risk, what type of reliability we design for and on.

00:43:21.467 --> 00:43:28.998
<v Thomas Gernay>And because it requires exploring a range of scenarios, also computational modeling is the natural tools to, to go around it.

00:43:28.998 --> 00:43:29.177
<v Thomas Gernay>Right.

00:43:29.807 --> 00:43:34.507
<v Thomas Gernay>And so the first thing I would say, , when you ask me about what's the future.

00:43:35.228 --> 00:43:51.878
<v Thomas Gernay>It's really more forward looking now, maybe I'm talking about 20, 30 years down the road, but I'm, I think we have this capability for modeling the non-linear response thermals to try in multiphysics of buildings against fire.

00:43:51.882 --> 00:44:02.077
<v Thomas Gernay>And that is great, but right now it still requires a lot of expertise and it's only done for some kind of iconic structures when you have the time and money and, and expertise.

00:44:03.297 --> 00:44:10.588
<v Thomas Gernay>Many people are working on other aspects of, uh, the built environment with digital tools, with numerical tools.

00:44:10.588 --> 00:44:26.766
<v Thomas Gernay>So we have linear, real, uh, software for the response, but more broadly we have BIM and we have, the ability to track, the construction process and moving forward, we need to do more about circular economy and sustainability reusability.

00:44:26.766 --> 00:44:27.846
<v Thomas Gernay>So probably there will be.

00:44:28.356 --> 00:44:34.536
<v Thomas Gernay>Digital ecosystems to track really all the components of these buildings and how they go together.

00:44:34.536 --> 00:44:35.016
<v Thomas Gernay>And so on.

00:44:35.496 --> 00:44:38.436
<v Thomas Gernay>I think that in the future, we should be able to.

00:44:39.050 --> 00:44:45.121
<v Thomas Gernay>Again, interface and couple and put together these different types of, numerical models.

00:44:45.181 --> 00:44:53.947
<v Thomas Gernay>And basically I think we will move toward having digital twins for all, complex objects, Aircrafts buildings and so on.

00:44:53.947 --> 00:44:56.590
<v Thomas Gernay>And maybe we'll have, in the metaverse or, or whatever.

00:44:56.590 --> 00:44:58.630
<v Thomas Gernay>We have the same cities that we have.

00:44:58.940 --> 00:44:59.360
<v Thomas Gernay>Here.

00:44:59.391 --> 00:45:11.733
<v Thomas Gernay>but with, this digital twin object that allows us to track all the resources, components and so on, but also to inigate the response against extreme hazards, fire, earthquakes, and so on.

00:45:12.123 --> 00:45:14.523
<v Thomas Gernay>And as the condition are changing, climate is changing.

00:45:14.523 --> 00:45:17.583
<v Thomas Gernay>We can change the stress source and we can change the demand and so on.

00:45:18.063 --> 00:45:18.784
<v Thomas Gernay>But I.

00:45:19.643 --> 00:45:25.014
<v Thomas Gernay>Structural fire modeling cannot stay apart from all those other digital efforts.

00:45:25.014 --> 00:45:33.226
<v Thomas Gernay>And basically we should have a, a digital ecosystem where we put everything together for modeling buildings and ensuring they are sustainable and they are resilient.

00:45:33.478 --> 00:45:41.384
<v Wojciech Wegrzynski>Based on my experience with how BIM is incorporated actually the, the structural engineering part makes a lot of sense to, to couple that.

00:45:41.384 --> 00:45:44.081
<v Wojciech Wegrzynski>So maybe it's not even, maybe it's not even decades.

00:45:44.081 --> 00:45:48.800
<v Wojciech Wegrzynski>Maybe it's just years ahead of us to, to have a, at least this part coupled because.

00:45:49.766 --> 00:45:55.376
<v Wojciech Wegrzynski>Coupling with, with CD modeling is probably a little harder because of other challenges.

00:45:55.802 --> 00:46:08.369
<v Wojciech Wegrzynski>the main being, you build model for a certain purpose architect drawing the building or engineer drawing, their structural model has a different purpose than CFD engineer.

00:46:08.429 --> 00:46:10.882
<v Wojciech Wegrzynski>It's just that simple and that problematic.

00:46:11.251 --> 00:46:11.851
<v Thomas Gernay>Absolutely.

00:46:11.851 --> 00:46:24.070
<v Thomas Gernay>It still requires a lot of human thinking to know how to model a structure for the purpose of structural for engineering, because you have to think about the heat transfer problem, then the structural response.

00:46:24.076 --> 00:46:36.846
<v Thomas Gernay>So you, discretized your structuring in a certain way, and it's not just lines on, on a sheet of paper that you can extra, you have to have a kind of information and data that today we don't have in, in other.

00:46:37.436 --> 00:46:54.449
<v Thomas Gernay>Pieces of this digital workflow, but as I look, you know, back decades and then I look forward several decades, I'm sure we'll find solutions for this kind of challenges, but indeed it's, it's not trivial because as you say you right now, each of these tools have very specific purpose.

00:46:54.809 --> 00:46:59.818
<v Thomas Gernay>And so you have to have an engineer who think about what's the right modeling approach.

00:47:00.358 --> 00:47:01.949
<v Thomas Gernay>To target this purpose.

00:47:01.949 --> 00:47:06.661
<v Thomas Gernay>And so to replace or to, to harmonize that, which requires some, lots of research.

00:47:06.777 --> 00:47:11.777
<v Wojciech Wegrzynski>And how you feel about emergence of AI as a support tool in the structural fire engineering.

00:47:11.826 --> 00:47:12.996
<v Thomas Gernay>I'm glad you bring that up.

00:47:13.001 --> 00:47:14.976
<v Thomas Gernay>That that could definitely help.

00:47:14.981 --> 00:47:20.400
<v Thomas Gernay>I think, we are still, Playing with the concept and trying to see where opportunities lie.

00:47:20.400 --> 00:47:33.833
<v Thomas Gernay>But if we start, being systematic about the data and collecting and classifying the data,  I don't see why AI could not help in this field the way it has helped in, in others.

00:47:33.833 --> 00:47:34.074
<v Thomas Gernay>Right.

00:47:34.074 --> 00:47:41.652
<v Thomas Gernay>So, uh, I think we are still relatively in, the early stage of the, the field of structural fire engineering.

00:47:42.012 --> 00:47:45.759
<v Thomas Gernay>And we are still, looking at these philosophical questions that you were mentioning, right.

00:47:45.759 --> 00:47:54.686
<v Thomas Gernay>That at the high level, we still don't have really the answers about oh, We do have the answers, but we have to think, hard about the scenarios and the performance objectives.

00:47:54.686 --> 00:48:05.157
<v Thomas Gernay>In all case, it's not really codified yet, but as this become embraced more and more, and as we move to a more systematic there, I think that, AI could also, uh, come in and help.

00:48:05.402 --> 00:48:06.586
<v Wojciech Wegrzynski>I hate doing this podcast.

00:48:06.592 --> 00:48:13.577
<v Wojciech Wegrzynski>Like, you know, I ask people to talk about their fancy tools and the most impressive stuff they've done and it always ends up.

00:48:13.577 --> 00:48:15.166
<v Wojciech Wegrzynski>Like we don't understand our objectives.

00:48:15.166 --> 00:48:16.396
<v Wojciech Wegrzynski>Well, fire.

00:48:16.597 --> 00:48:17.556
<v Wojciech Wegrzynski>Safety's horrible.

00:48:17.976 --> 00:48:20.177
<v Wojciech Wegrzynski>We need to start our objectives guys.

00:48:20.177 --> 00:48:20.657
<v Wojciech Wegrzynski>Come on.

00:48:20.706 --> 00:48:21.456
<v Wojciech Wegrzynski>, I want more.

00:48:21.717 --> 00:48:25.786
<v Wojciech Wegrzynski>Exciting stuff in the podcast just bragging about how we don't.

00:48:25.817 --> 00:48:28.726
<v Wojciech Wegrzynski>But yeah, that is the sad reality..

00:48:28.786 --> 00:48:40.907
<v Wojciech Wegrzynski>Like that is truth that we spend so much money and effort on many, many fancy things and minuscule improvements in secondary

00:48:41.166 --> 00:48:41.257
<v Thomas Gernay>Where.

00:48:42.407 --> 00:48:43.157
<v Wojciech Wegrzynski>where.

00:48:43.942 --> 00:48:47.931
<v Wojciech Wegrzynski>We don't have a fundamental question answered.

00:48:47.931 --> 00:48:51.952
<v Wojciech Wegrzynski>Like, do we want our structures to resist burnout or not?

00:48:51.956 --> 00:48:53.751
<v Wojciech Wegrzynski>And, and how to choose if we want it.

00:48:54.079 --> 00:49:02.929
<v Wojciech Wegrzynski>we have not answered the question of what design fire and that what probability is, is, for this building and how it would be for another building.

00:49:03.309 --> 00:49:05.186
<v Wojciech Wegrzynski>It's Overwhelming, but I'm happy.

00:49:05.186 --> 00:49:06.655
<v Wojciech Wegrzynski>We have lots of work.

00:49:06.746 --> 00:49:08.876
<v Wojciech Wegrzynski>Uh, future of fire engineers is bright.

00:49:09.635 --> 00:49:19.326
<v Thomas Gernay>Well, these are complex questions, but to some extent, because there is such a multiplicity of, of buildings and projects and, uh, jurisdictions and, and everything.

00:49:19.326 --> 00:49:19.505
<v Thomas Gernay>Right.

00:49:19.505 --> 00:49:25.775
<v Thomas Gernay>I think what is key is to really move forward in providing the tools and the framework to.

00:49:26.085 --> 00:49:28.996
<v Thomas Gernay>Post approach these questions in a systematic way.

00:49:29.025 --> 00:49:37.918
<v Thomas Gernay>Once we make the decision, we want to go that way such as performance based, and then the tools to enable the assessments to be rigorous and rooted in the physics.

00:49:37.918 --> 00:49:40.918
<v Thomas Gernay>And that's really what computational modeling does that.

00:49:40.923 --> 00:49:50.898
<v Thomas Gernay>It gives you an understanding of the physics of the problem in terms of how the fire is going to develop and then how the structure is going , to respond, right, as opposed to taking a simplified model, which is.

00:49:51.548 --> 00:50:01.509
<v Thomas Gernay>Useful for benchmarking, but which does not give you these insights and the sensitivity and so on, but it's true that then you move to the higher level and it becomes a human decision problem.

00:50:01.509 --> 00:50:05.199
<v Thomas Gernay>And so we cannot formalize it the same way as engineers, because.

00:50:05.385 --> 00:50:10.222
<v Thomas Gernay>You need to speak with the stakeholders and it'll depend on the economics and on the social and so on.

00:50:10.731 --> 00:50:24.648
<v Thomas Gernay>So, uh, it's, it's true that it can seem frustrating, but to some extent, I think it's, once you move the needle from the, the engineering problem to, to all of the technical social problems that, is just different different considerations.

00:50:24.713 --> 00:50:32.626
<v Wojciech Wegrzynski>I wonder if in 50 years we'll still be thinking Mindset of fire resistance and, and how, how we'll develop.

00:50:32.666 --> 00:50:35.396
<v Wojciech Wegrzynski>I'm happy to view as this develops Thomas.

00:50:35.420 --> 00:50:37.000
<v Wojciech Wegrzynski>that was a great talk to you.

00:50:37.000 --> 00:50:51.264
<v Wojciech Wegrzynski>I'm very thankful for taking me into the world , of structural fire engineering and I'm, I'm sure it was interesting, probably more interesting to non-structural fire engineers, because we finally got an insight to how you guys do your.

00:50:52.061 --> 00:50:53.458
<v Wojciech Wegrzynski>so, yeah, huge.

00:50:53.458 --> 00:50:53.833
<v Wojciech Wegrzynski>Thanks.

00:50:53.855 --> 00:50:59.114
<v Wojciech Wegrzynski>and, I hope to see you here again with another interesting subject

00:50:59.199 --> 00:50:59.860
<v Thomas Gernay>Well, thank you.

00:50:59.860 --> 00:51:01.539
<v Thomas Gernay>It was just really my, my pleasure.

00:51:01.539 --> 00:51:04.090
<v Thomas Gernay>I had lots of fun discussing and I hope to see you soon.

00:51:04.119 --> 00:51:05.170
<v Thomas Gernay>They may be at the summer school.

00:51:05.894 --> 00:51:06.855
<v Wojciech Wegrzynski>that I would love that.

00:51:06.855 --> 00:51:07.875
<v Wojciech Wegrzynski>Thank you very much.

00:51:08.835 --> 00:51:12.945
<v Wojciech Wegrzynski>And that's end of this episode, I thought about making a fancy out ultra as usual.

00:51:12.945 --> 00:51:17.266
<v Wojciech Wegrzynski>But in fact, the end of this discussion has pretty much covered it all.

00:51:17.686 --> 00:51:22.865
<v Wojciech Wegrzynski>We're talking about fancy tools, , AI, bam integration, and other stuff.

00:51:22.865 --> 00:51:37.168
<v Wojciech Wegrzynski>While we don't have objectives and design scenarios fixed, and that's  kind of devastating, really, I feel really sad about the fact that we still do not have this seemingly simple, but as Thomas said, quite complex stuff figured out.

00:51:37.168 --> 00:51:49.065
<v Wojciech Wegrzynski>And if you're a researcher in the field and you want to find a place where you can make great impact, well, there it is  this is a much needed place for research.

00:51:49.456 --> 00:51:55.155
<v Wojciech Wegrzynski>And while we are developing that structural fire engineering is there to help us understand the behavior of the whole structures.

00:51:55.606 --> 00:51:58.365
<v Wojciech Wegrzynski>We hope we've pretty well highlighted.

00:51:58.365 --> 00:52:10.833
<v Wojciech Wegrzynski>The difference between the performance of a member performance of a single element in your building and the performance of the whole building itself at The example of Cardington and a membrane action in the slabs , is a perfect example of that.

00:52:11.182 --> 00:52:12.543
<v Wojciech Wegrzynski>How, how different it is.

00:52:12.543 --> 00:52:19.472
<v Wojciech Wegrzynski>Like if we just focus on performance of single members, as we usually do, how do you understand the performance of the whole structure?

00:52:19.503 --> 00:52:20.762
<v Wojciech Wegrzynski>How it will behave in the fire?

00:52:20.773 --> 00:52:22.932
<v Wojciech Wegrzynski>Will it behave better, will behave worse.

00:52:23.382 --> 00:52:23.623
<v Wojciech Wegrzynski>Yeah.

00:52:23.682 --> 00:52:27.737
<v Wojciech Wegrzynski>Luckily the current experiences that they usually behave better.

00:52:27.737 --> 00:52:32.628
<v Wojciech Wegrzynski>And Thomas mentioned that these actions that were found made the buildings more robust.

00:52:32.628 --> 00:52:38.867
<v Wojciech Wegrzynski>So even some requirements could have been softened down on the secondary members.

00:52:39.047 --> 00:52:45.181
<v Wojciech Wegrzynski>It's really interesting how understanding fire science can significantly improve the way, how we design structures.

00:52:45.181 --> 00:52:46.170
<v Wojciech Wegrzynski>Some has also mentioned.

00:52:46.601 --> 00:52:48.670
<v Wojciech Wegrzynski>New Euro codes coming up.

00:52:48.880 --> 00:52:53.911
<v Wojciech Wegrzynski>And, for those who don't know, Euro codes is a series of standards in European union.

00:52:53.911 --> 00:53:05.554
<v Wojciech Wegrzynski>They're free to access, publicly available and they have, Plenty of information on structural engineering and structural fire engineering with all modern materials.

00:53:05.943 --> 00:53:10.384
<v Wojciech Wegrzynski>I really found interesting that he mentioned, uh, Luxemburg annex to eurocode, which covers glass.

00:53:10.384 --> 00:53:14.914
<v Wojciech Wegrzynski>And I must really jump into that because , it's super interesting topic to me at this point.

00:53:15.434 --> 00:53:20.574
<v Wojciech Wegrzynski>I hope it was not too heavy for summer break, but, , I guess,, fire science , is just great.

00:53:20.603 --> 00:53:23.018
<v Wojciech Wegrzynski>Even if it's even if it's hard, it's still great.

00:53:23.349 --> 00:53:30.231
<v Wojciech Wegrzynski>I hope you've enjoyed this episode and I hope to see you and I hope to see you here again next Wednesday.

00:53:30.380 --> 00:53:30.831
<v Wojciech Wegrzynski>Thank you.

00:53:30.831 --> 00:53:31.431
<v Wojciech Wegrzynski>Cheers.