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NEESWood Webcast Transcript


JOSH CHAMOT: Good morning. I'm Josh Chamot. Welcome to the National Science Foundation. Just a few hours ago, at the E-Defense facility in Miki City, Japan, a little north of Kobe, engineers conducted the world's largest ever shake table test. The engineers' goal--prove that their design for a six-story wood frame condo building can survive the 1994 Northridge, California, earthquake, amplified to 180 percent of its original intensity. That quake, that shake was larger than any quake that California has experienced in modern time. Let's go ahead and see the tape.

Joining us via telephone from Japan to talk about how to build a condo building that doesn't fall over in an earthquake, is John van de Lindt, Associate Professor in the Department of Civil Engineering at Colorado State University and the principal investigator for NSF's multiyear NEESWood project; Hidemaru Shimizu, a research collaborator with E-Defense facility in Japan's National Research Institute for Earth Science and Disaster Prevention; Hiroshi Isoda, the Associate Professor in the Department of Architecture and Civil Engineering at Shinshu University in Nagano, Japan; and joining us also from Japan is Edward Matsuyama, Director of the American Forest & Paper Association's office in Tokyo, and he's also going to be assisting, as necessary, translating between Japanese and English. And in the studio with me is Joy Pauschke, the director of our NSF Network for Earthquake Engineering Simulation program, or NEES, and she has supported the NEESWood effort since its inception in 2005.

Throughout the broadcast, if you'd like to ask a question at any point, just press *1 on your touchtone phone and you'll be placed into a queue. If you'd like to email a question in, just send one in at webcast@nsf.gov. Just note that when you send your request in, if you call, that there is a delay between this webcast and what you'll hear on the phone so you'll want to turn your computer speakers down. One final note, this is being recorded and it will be rebroadcast later in the day.

So, John, that was a impressive test in the sense that the thing did not fall over. Did you get what you expected today?


JOHN VAN DE LINDT: Yeah. Hi, Josh. Yeah, absolutely. I think we had a very successful test. Basically, there was a 2000 500-year earthquake we subjected the building to and it wound up – basically wound up performing very, very well. We were expecting moderate damage but it turned out that we had very, very light damage to the building, and so in the end, after going in and inspecting, I think we proved exactly what we were set out to prove. We did this with about 300 sensors in and around the building and about 50 optical tracking devices on the outside of the building.

JOSH CHAMOT: So we don't really expect a building to withstand that kind of shaking and not fall over, especially one made of wood or that tall. Clearly, this is a different way of doing things. What did you guys do exactly and how is this going to impact construction in the future in the United States?

JOHN VAN DE LINDT: Well, what we did with this building was we, during the NSF project, we developed a philosophy known as Performed-Based Seismic Design. This has been developed for steel and concrete and this is really the first time that there's been any major development in this for wood structures. And so, what I see is I see probably major developments over the next six months to two years in the design code industry within the U.S. will be pushing to have buildings be five, six, even seven stories throughout the Pacific Northwest and all around the U.S. as a result of this project.

JOSH CHAMOT: You know, and one of the questions we just got in expands that a little bit. It's from Laurie Wiegler in New York. She's a freelance science writer and she's bringing up infrastructure itself. She's mentioned that in the U.S., many bridges are in a state of disrepair. Have similar tests been conducted for bridges and infrastructure and how do the results that you did today apply? And after you're finished, I'll turn to Joy because I know that other NEES projects are addressing this as well.


JOHN VAN DE LINDT: Yeah. Well, I think the way that we do research certainly applies the methods and the techniques. You know, what we've done today doesn't – it indirectly applies to bridge structures. I think much of that work is being done at a different NEES site in the University of Reno, at University of Nevada at Reno and maybe I'll pass that to Joy later and let her answer a little bit about some the bridge work that's going on.

JOY PAUSCHKE: Thanks, John. I'm happy to follow up. NEES funds a number of different types of projects that are investigating seismic design, new designs and retrofit designs for buildings, bridges, support structures. We even look at non-structural systems and with respect to infrastructure, we've used NEES to do research on investigating the performance of bridges. One of the NEES facilities has been used to test bridges has been the NEES facility at the University of Nevada, Reno. That's a very unique site because it has three shake tables. So, recently, they tested a 4-span quarter scale bridge. It's the largest bridge that's been tested to date in a laboratory, and they tested the bridge using really new materials that haven't been incorporated into bridges such as shape memory alloys and Elastomeric bearings. So there's a follow on test that's being funded by the Federal Highway Administration that's going to use the four shake tables that we have at the University of Nevada, Reno and test a curb-span bridge. We also have tested lifelines facilities, pipelines. Those facilities, such as pipelines and conduits that carry water, telecommunications, that you want to maintain operations immediately following an earthquake and the Cornell facility has tested a number of lifeline pipelines up there and they have really produced a very comprehensive database on how pipelines that are subjected to fault rupture can perform during an earthquake. So, that's the NEES facility at Cornell.

JOSH CHAMOT: Great. And getting back to the building we're looking at here. One of the questions we have is how did you get the data that you were looking for from the structure? I imagine there are sensors everywhere. I imagine there were a lot of cameras inside. What have you gotten from it and how does that build on what you've been learning through the last four years of this study?


JOHN VAN DE LINDT: Yeah, that's a great question. We have about 300 sensors inside. These range from, you know, measuring different displacements to measuring strains in, you know, various steel parts that are incorporated into the wood design, and then we have 50 LED sensors on the outside that actually are tracked with high-speed cameras so we can optically track the movement and so actually when we test, the curtains are drawn in the lab, the doors are closed and it's not dark, but it's certainly light enough to see by camera and by eye, but the way we track the movement of that is done with a special software package. Basically, to do all this, to gather all this data, and many, many cameras as well, to gather all this data, we then can use this data to validate our design methods that we've developed over the last few years as well as validate a lot of the software that we've been developing throughout the NSF project.

JOSH CHAMOT: And this builds on the work from Buffalo and I think we actually have some footage from the Buffalo test. I'm not sure which clip we're going to show, but that test began – I guess the first test ran in 2006, was it, and what did you start the project with? What was the goal here?

JOHN VAN DE LINDT: The goal of the project?

JOSH CHAMOT: Yeah, starting with Buffalo and then to now, but I know there were some differences.

JOHN VAN DE LINDT: Sure. The goal of the Buffalo test was – it was called the benchmark test within the project and the objective of the benchmark test was, as the name implies, to kind of benchmark the current state of construction in the U.S. for light-frame wood buildings. We also got to see that we were lacking some details in our current numerical software, and so since that time we've been able to improve on those quite a bit and so now we're able to model these buildings much, much better and I think that contributed to the success of today's test.

JOSH CHAMOT: Great. OK. And let me throw a question also to our colleagues who are joining us from Japan as well. I guess this would be for Hiroshi. I know that your expertise involves different building methods between Japan and the United States. I had heard that during construction, there were some starting points where the team had to work with the carpenters to build this structure in an American style. How do the styles differ in Japan and the United States, and are there things that Japan has learned from this test that they can apply to their own structures or are the building types too different to make those comparisons?

Edward, are you there?


EDWARD MATSUYAMA: Yeah. I'm just waiting for him . The main focus of this test is that two-by-four construction or frame construction can be [inaudible] and with such an earthquake.

JOSH CHAMOT: So to focus on the height and structure, are there any differences between the approach or what can be applied from this to other structures around the world? Are there differences between codes that become a problem?

EDWARD MATSUYAMA: What do you mean by codes?

JOSH CHAMOT: So that there are different ways of building in the United States and in Japan. So, is this applicable in this – the construction methods that were used, are those applicable to the way construction is done in Japan?

EDWARD MATSUYAMA: Yes. He said that this is definitely applicable to building construction in Japan as well.

JOSH CHAMOT: Great. Okay. Thanks. John, let me go ahead and get back to you with a question about what's been developed in terms of the software. You guys have been using all of these tests to gather data points that are actually helping you design new structures and you mentioned as well retrofit existing structures. What is this software? How is this going to be done?


JOHN VAN DE LINDT: Well, the software itself is basically a – kind of serves a dual purpose. It serves the purpose of a research tool so it has, you know, those complexities that we need for modeling, but then it also has a graspable user interface and has the ability to be available for practitioners. In other words, in certain instances the usage is at the usable level for practitioners rather than as a research tool, and so what we did was we basically gathered industry feedback following the Buffalo test on the software package and put together a workshop in Boise, Idaho, about a year ago , a year and a half ago now and gathered industry feedback as a result of that workshop and then improved on the code from the user perspective. Then from a research tool, of course, we're able to, you know, improve upon that from our own perspective.

JOSH CHAMOT: Great. I'd like to remind everybody at this point that if they do wish to ask a question by phone, all you have to do is press *1 and you'll be placed in the queue.

We have a question right now from Ghasan Doudak of the Canada Wood Council. Ghasan, are you on the line?

GHASAN DOUDAK: Uh [inaudible].

JOSH CHAMOT: I'm sorry. I'm having trouble hearing you. Let me see if we can get the sound up. Ghasan, are you there?

GHASAN DOUDAK: [Inaudible].

JOSH CHAMOT: I guess we've lost that call. In the meantime, let me go ahead and turn to Joy. I know there have been a lot of projects going on with NEES this year and there are some developments that kind of work together. The NEES network is more than just this one effort and, in fact, involves 15 different facilities in the United States. What are some of the developments that have occurred this year at some of the 15 different facilities here?


JOY PAUSCHKE: We've been testing – networks has been very busy over this past year. For example, recent tests were done at the University of California, San Diego. They were testing masonry in-filled structures. We've tested bridge structures at University of Nevada, Reno. We're continuing to test, for example, at the University of Illinois, several different types of structures and we have projects coming up at the E-Defense as well.

JOSH CHAMOT: Great. OK. And we have another caller on the line. This is James from Structural Engineers. James, can you hear us?

JAMES: Yes, I can.

JOSH CHAMOT: Great. Go ahead with your question.

JAMES: I don't have a question. I'm just listening in.

JOSH CHAMOT: OK. All right. Thanks. All right. Moving on. John, I wanted to talk to you a little bit about maybe getting back to the question that I'd referred to earlier with Hiroshi. I know that there were some – when you got there, you had to rebuild some of the structure because of some differences in approach, and one of the things that you had told me about was that these findings aren't only applicable to United States, that there ways that even though there are very different construction methods around the world, there are ways the findings can be applied. Can you get into a little bit about that?

JOHN VAN DE LINDT: Yeah, absolutely. I think – and what I meant by that was that what we've developed in this project is really a design philosophy, and so while the construction methods or the construction techniques around the world might differ from country to country or continent to continent, we still have the ability to, for instance, in this case, it's a Performance-Based Seismic Design but we still have the ability if we can just model whatever type of structure it is, to say we want a particular performance from that building or from that bridge or whatever it is, and to go ahead and then figure out, you know, how we have to get that performance, and so it's kind of an input/output problem. And in doing that, you know, we've demonstrated that we can do that for a very complex structure to model, which is a six-story light-frame wood building and in demonstrating that, I think that that type of approach is certainly applicable to any building around the world.


JOSH CHAMOT: Great. And we actually have a related question coming in by email from Gail at Redondo Union High School. She's asking about was a six-story wood frame condo building used fully stocked with items like a real house would be? Was there weight on the upper floors due to furniture and other belongings that would be expected if it was an occupied building? I've also wondered how would the impact of pipes and wires affect the building structure, which is, I know, something that one of the NEES centers focuses on specifically, but is that work into any of the equations at all?

JOHN VAN DE LINDT: Yeah. That's a great question because that's something we have to deal with when we test buildings. In the case of this structure, it's not very cost advantageous during testing to put all the furniture in and, you know, detailed painting and hang pictures, things like that so what we did was we just basically furnished one small room to see the effect on the furniture, things like that. But what we also do is we then bolt steel plates onto the floor so we had around over 100,000 pounds of steel plates in the building. Those were provided by the E-Defense facility by Hidemaru Shimizu that's on the call also, and those are basically bolted in and those represent the lightweight concrete that you would have on the floor diaphragms which would prevent sound transmission between apartment units, things like that as well as it would represent furniture or other types of weight in there. So, we do have the correct seismic weight, we just don't have the look of a real building inside always.

JOSH CHAMOT: Sure. And I know that for the Buffalo test that there actually was even furniture and toys in the children's room. I think actually we're running a clip of it right now showing the shaking from inside that children's room and I believe – what was the strength of this test, of the Buffalo test?

JOHN VAN DE LINDT: I'm sorry. What was the –

JOSH CHAMOT: The strength of that quake?


JOHN VAN DE LINDT: Oh, that was a Northridge earthquake also. So, the one you're seeing there was actually a near-fault motion known as the Renaldi recording station, and that's a very large, kind of a high-velocity volt so that's – in the earthquake, you'll see – if you're watching the video, you'll see it vibrate kind of vertically and then one really large horizontal pull that will throw everything and that's kind of characteristic of these near-fault motions.

JOSH CHAMOT: Great. And just to clarify because we keep calling it the Buffalo test, that was one of the collaborating universities is Buffalo University and they have their own shake table as part of the NEES project, NEES system, and that's where that test was held. We have another question that came in from Johnny Marks in San Antonio, Texas. This was emailed. He says it certainly went well. Do you foresee residential homes incorporating damper methods in the future here in the U.S.? He says he's been observing for almost four years and he says, "Is it just me or has there been more seismic activity over the past year?" I don't know if we can answer the second part, but in terms of the damper methods and maybe you could get into some real specifics here about what were the technologies that kept this building up.


JOHN VAN DE LINDT: Yeah. Sure. You know, I think with a single-family home, it becomes kind of a cost issue. In other words, can you derive as a cost benefit? Can you derive enough benefit or enough reduction in risk to warrant spending the cost up front for dampers or base isolation, things like that, these advanced techniques, and I think in many cases, you can. Certainly with a meterized light-frame building like we tested, I think we could justify that type of system. For the most part, in our building, we didn't actually have dampers or base isolations in the building that was tested today. What we had was we had an anchor tie-down system, which is steel rods that go from the base of the building all of the way up to the roof level and those, they basically – there's a bearing placed at each story and so the rod then – what it does is it basically keeps the shear walls, which deform horizontally, it keeps those from trying to turn over. And so it basically keeps the building from tipping over, I guess you could say, and that's very, very important. The other thing that we had that was, I guess, a technological innovation, so to speak, or maybe a design innovation was the design method itself. This Performance-Based Seismic Design method allowed us to distribute, you know, say, kind of distribute the, or kind of govern the way the building deforms when it starts shaking and that certainly helped quite a bit.

JOSH CHAMOT: So what usually causes a building to fail in a quake and how are you going to retrofit buildings to address that based on what you learned from today?


JOHN VAN DE LINDT: Yeah, what usually causes a building to fail is something called a soft story, and what that is is if you think of the Kobe or the Northridge earthquake, what happened was, well usually the bottom story may not be quite as stiff as the stories above it and so the minute it starts to – the minute it takes a little bit more load, it starts to move a little bit more, then it basically deforms more and more, almost like a cumulative effect in a way, and it begins to deform and then the upper stories that are stiffer, they take no loads so the bottom story takes it all and it basically collapses, and this actually, most of the people that died in the Northridge earthquake and certainly in the Kobe earthquake, died as the result of soft story collapses, and so what our design method does is it basically designs the building in such a way that we can avoid the soft story collapse and so we didn't see a soft story at all today in the shake.

JOSH CHAMOT: That's great. We have actually another line call. Before I get to him, I want to remind everybody, if you do want to ask a question, just press *1 on your touchtone phone. This is Ugo Morelli from FEMA. Ugo, can you hear me?

UGO MORELLI: I'm retired from FEMA.

JOSH CHAMOT: And did you have a question?

UGO MORELLI: I'm no longer active federal employee. I'm retired.

JOSH CHAMOT: OK. And did you have a question for John?

UGO MORELLI: I was wondering how I could get the webcast online. I went through all the procedures and all I get is a dark screen with some wording about NSF.

JOSH CHAMOT: Sure. Just dial into – send an email to webcast@nsf.gov and we'll get somebody to go ahead and fix that for you.

UGO MORELLI: I'm sorry. I can't hear you.

JOSH CHAMOT: Send an email to webcast@nsf.gov and we'll get somebody to fix that for you. OK? Thanks.

We have an email question from Andy Paddock. He's a structural engineer in Colorado Springs and he's apparently a graduate of CSU and a practicing structural engineer right now. He said do the provisions of the 2006 IBC, which I guess is a code you'll have to explain here real quick, for the shear calculations, did you use those? Basically he's asking what did you use to calculate your motions and your shear and how do they compare to what was tested? So, how do your models compare to what you actually observed and do you think that the current standards, and in this case he's mentioning IBC, but just overall do you think the standards are accurate? Are they where they need to be?


JOHN VAN DE LINDT: Well, yeah, that's an excellent question, Andy. What we've done in this test is we actually designed not to the DBE level, but this building was designed to perform very well at the MCE level so that's about 150 percent of what we call the design basis earthquake.

JOSH CHAMOT: And do you want to quickly just explain what those definitions are?

JOHN VAN DE LINDT: Yeah. The DBE is the Design Basis Earthquake and that's the kind of, the seismic intensity level that structural engineers use in the United States to design. The MCE level is about 1.5 times that and that's actually typically not used in design. It's basically what we get from geologists and seismologists. They pass that to the engineers and then we typically take a two-thirds factor on that which reduces that. In this case, we didn't reduce that and the idea within the project was to demonstrate that we could design a six-story building at this much, much stronger level, much stronger seismic intensity level. That was really one of the big objectives, and so all in all, what we did then is then we went through and designed a system and so that's really one of the things with this type of design method is we're kind of designing in reverse. We're treating it as a big system level problem, seeing how the system responds and then we go back and check the components or subassemblies. Subassembly might be like a wall or something, whereas in IBC style design, you might design various walls and then you piece them together and assume that the performance would be at least as good as the wall, and that's actually not always the case and so that's one good argument for Performance-Based Seismic Design.

JOSH CHAMOT: Actually, when you talk about the walls, that relates to a question we just got from Casey Talon, who's an engineer in Brentwood, Texas, talking about the outside of the walls. He mentioned that the test didn't appear to consider siding or stucco on the exterior and he talks about how that would increase the stiffness of the structure. So, did you somehow take that in consideration when you did your modeling?


JOHN VAN DE LINDT: Yeah, we did, actually. We took that exactly into consideration. In other words, in the Performance-Based Seismic Design approach, we did consider the drywall in the structures. That was accounted for in the design, but we didn't consider stucco, which would – she's absolutely right, would add quite a bit of stiffness. We didn't consider any kind of siding, and so from the perspective of actually validating a design method, which is what we were trying to do at this test, if we didn't consider it in the design, then we're still fine. We certainly would have liked to but I think just, you know, various constraints on the project that that wasn't really a possibility but we, if anything, we can consider the results maybe slightly conservative, which we all know is great from an engineering standpoint.

JOSH CHAMOT: Sure. Sure. We have another question from a student. This is Bob Okiai at Perdue University and he says that since the test proved to be successful, are you going to move towards developing a material that's close to it? I mean, obviously you wouldn't but maybe testing that, and he said he's unaware of synthetic materials that are close characteristics to wood but he's looking at the possibility of resisting burning and aging and things like that, the problems that wood tend to face. So, there are a couple questions here. One that we talked about before the broadcast, which is fire can be an issue. Some of these things do come up. Are alternate materials that may benefit from the test results that you saw today and regardless of that, is the wood itself something that's a safe structural material to use and why?

JOHN VAN DE LINDT: Yeah, I think one of the things when we began the process of even writing the proposal and then into the project was that we kind of limited the scope in a way to the structural or the seismic aspects, realizing that, you know, of course, all along the way that fire is an issue for these taller buildings. I think the idea of performance-based design, not even just Performance-Based Seismic Design, but any kind of performance-based design is to really almost try and fuel innovation from industry. And so in laying this out and saying well, we can do the seismic part, we can demonstrate that and now we leave it to the material experts and the fire experts and the developers or we, you know, certainly would work with them but we leave that to them to then come up with a material and, you know, in my experience, you know, just kind of watching as I go through projects, if somebody can develop a material or something that does work and they can profit from it, then certainly industry will do that. And so I think, you know, what he mentioned is probably going to happen, I suspect.

JOSH CHAMOT: Great. We have another question that came in from another structural engineer. This is Boyd Zander. He's in Lombard, Illinois. He actually is asking about the shake table itself, which is E-Defense, and he asked if it was developed for this project and it was not and he asked because it was used for light-frame construction, will it also be used to test other types of system, concrete and so on? Edward, can you hear us?


JOSH CHAMOT: Let me go ahead and pass this to you guys. When was E-Defense created and what sorts of structures are tested on there? I imagine there's a range; it's not just wood frame.


EDWARD MATSUYAMA: E-Defense actually built [in audible] 2005.

JOSH CHAMOT: OK. And do you do tests on it with more than just wood frame construction, I imagine?

EDWARD MATSUYAMA: And up until now, six-story concrete, seven-story wood has been tested on it, on this shake table, and also a lot of buildings in addition to this as well.

JOSH CHAMOT: Great. And I imagine there was also – I believe there were some houses and smaller structures too?

EDWARD MATSUYAMA: Yes, obviously some single-family as well.

JOSH CHAMOT: Great. And single-family home is obviously what was tested in Buffalo as well. Did you have something to add to that?

JOY PAUSCHKE: Yeah. Josh, I just wanted to add that the Network for Earthquake Engineering Simulation was the result of really assessing the experimental capabilities in the United States to do further tests on seismic designs so we don't have to wait for another earthquake in order to learn how to build structures to better withstand earthquakes. So following the 1989 Loma Prieta and 1994 Northridge earthquakes, as a result of those two earthquakes, NEES actually was formed then and became a project that NSF funded construction at 15 facilities around the United States to build these types of testing facilities including shake tables, geotechnical centrifuges, large laboratories that can test all sorts of structures, lifeline structures, soil structure interaction. We have a tsunami wave basin and then we have some mobile shakers that can go out in the field and test structures or do all sorts of site characterization. The same time that 1995 Kobe earthquake happened and so the E-Defense shake table was really built to help Japan really design more earthquake-resistant structures as well. Both NEES and the E-Defense facilities came online roughly within about six months of each other. The U.S. and Japanese researchers have had longstanding collaborations and so now with these two types of facilities online, NEES and E-Defense, this was really a great opportunity to form a partnership so the National Science Foundation and Japan's Ministry of Education, Culture, Sports, Science and Technology have a memorandum concerning cooperation in the area of disaster prevention that facilitates researchers from both countries to utilize NEES and E-Defense facilities, and this NEESWood project is one that's a result of this memorandum.

JOSH CHAMOT: Great. Great. We have another question from Don Petty, who's a senior building official for the District of Saanich. It doesn't say where that is. He said the subject of a building typical of one constructed – he asked if the building was typical of one constructed to some code or standard or did it include significant upgrades or specialty changes in anticipation of the severity of the test? I think the response would be that you guys are intending that this would become part of code, correct?


JOHN VAN DE LINDT: Yeah. That's exactly right. It was designed, as I mentioned earlier, to the MCE level so it was designed with a more severe or stronger seismic intensity in mind. Probably the two details is that it was designed to only deform laterally a certain amount and then the steel rods, basically called anchor tie-down systems, those were designed to only deform or elongate a certain amount. It was actually exactly a quarter inch per story level, but that accumulates as you go up and so by the time you get to the top story, that rod has effectively elongated an inch and a half, and, so what that means is the wall actually has to deform a full inch and a half – or sorry, excuse me, the uplift is about an inch and a half until the shear wall actually starts resisting and then, of course, if we make that too large, then the building can tip over.

JOSH CHAMOT: Interesting.

JOHN VAN DE LINDT: But the short answer is yeah, this is certainly intended to go eventually into the code and become an option and it's an option to design to a higher seismic intensity for better performance.

JOSH CHAMOT: Great. We now have a question that's more related to the quake itself that would cause the damage. You've just addressed aspects of the construction. This is from David Lintner in Claremont, California, who is addressing aspects of the quake. There are different types of quakes, and I won't get into the details. He mentions strike slip versus dip slip and the different faults cause different quakes and different types of motion. Do different types of shaking cause different results in the building? I noticed that a lot of you guys use Northridge as your standard for a lot of the tests. Is there a reason for that and what other types of quakes might have a different impact on how the buildings respond?


JOHN VAN DE LINDT: Yeah. Typically, of course, we're not seismologists. We're structural engineers and structural engineering researchers and so usually the seismologists or the structural engineer/seismologist will pass the ground motions to us and there is a difference, certainly. I mean, if we have – but from a structural engineering perspective, we're more concerned with what we call the ordinary records, OGM, Ordinary Ground Motions, or Near-fault Ground Motions and so we have the near field and the far field, and that causes a very different effect and its effect on structures is very different. The type of earthquake itself, when we get into the far field, that I probably – certainly I'm not a seismologist, but we typically, if there's various faults around, we'll typically use suites and ground motion so we account for all those kind of – by analyzing the building to maybe 20 or 30 different ground motions and so some of those might be strike slip, some of those might be dip slip, various fault types. So we do account for them all.

JOSH CHAMOT: Great. We have another question that came in from Scott Good. He didn't give his town. He asked about how the performance of the basic type of structure tested today would compare to one that has extra weight and rigidity of drywall and stucco, which actually came up earlier. But I guess this leads to the question of what comes next? What other components do you need to test? What other structures and components do you need to add to the building to get a more realistic test in the future, or are you going to work now on components and focusing on improving those?


JOHN VAN DE LINDT: I think the next step for us, I think, is really to go back and, you know, now that we've validated models and we know the design method works is to go back and look at some of the buildings that are actually out there and to see if, you know, what types of tools and methods are available for a retrofit. So, I think a lot of the very fundamental work is done with this project and to look at actually getting research into practice as quick as we can and, you know, by getting this into the code, making it an option and then developing tools to actually retrofit these three, four, five-story wood buildings that are out there with a performance-based approach.


JOY PAUSCHKE: You know, if I could just follow up Josh.


JOY PAUSCKE: You know, a key point, I think, is that all of the experiments that have been done using the University of Buffalo, the two-story townhouse that was tested there in 2006 and then this experiment at E-Defense over the last month, all the data from these experiments will be archived in the NEES data repository. So, any of you who have been calling in who are structural engineers who'd like to use the data, will eventually have access to that data. It's a public repository so you can then use this experimental data to do all sorts of simulations and model validations as well.

JOSH CHAMOT: And getting back to –

JOHN VAN DE LINDT: And if I could just add that there's also – on the benchmark test, there's actually about an 800-page report available within that repository that has details, the location of every sensor, tells exactly how it was calibrated and so there's really almost enough to – definitely enough to be able to do your own analysis, do things, and then the software that we've developed is available free on the NEESWood webpage. You can just Google the word "NEESWood" and download the software with a user's manual and try it out and if you have any questions, you know, there's instructions on how to get in touch with us if you would like to get some support, and it's all free.

JOSH CHAMOT: And getting back to some of the questions. We've been getting a couple more engineering-related ones and these were related. One is from Larry Stevig in Bloomington, Illinois. The other one is from John Lawson from Kramer & Lawson Engineers; doesn't give his location. But both talked about some of the specifics like the maximum amount of motion that you saw in terms of drift and things like that, and what level to match design criteria, which you already addressed, but a lot of people have been asking about the acceleration and how much motion you saw. Were you able to measure that from the sensors you had on the outside of the building?


JOHN VAN DE LINDT: Yeah, we were, actually. We had about 35 accelerometers in the building and those measure absolute displacement and what we saw was, up at the 7th level where we had the one small furnished room, you know, certainly the chair and tables fell over and the flowers came off, you know, the various things, but really what we saw was we only saw right around maybe 2G of acceleration, and now while that seems high and it's certainly enough to make you fall over or knock you off your feet, for a building of this height and this stiffness, that's actually, you know, very good. I mean, certainly, you know, other types of buildings might have much higher acceleration, and so – and that was taken into account in the design approach. We had to kind of try and – because the stiffer we make a building, the stiffer and stronger, the higher the accelerations and so we had to kind of weigh these competing objectives, I guess, if you will.

JOSH CHAMOT: And I guess we'll go ahead and just address a last point, which is that the test, obviously, was for a California quake and I know that some of the standards you've been using have been related to California, but what regions of the country are you expecting to be able to apply this study?

JOHN VAN DE LINDT: Yeah, I think this can actually be applied anywhere. I mean, even beyond the U.S. Certainly in Canada and certainly anywhere that light-frame wood is constructed. But, I think where we'll see this type would be certainly all along the Pacific Northwest all the way up into Oregon, Portland, Seattle and over in the Missouri area in New Madrid fault zone. Basically, any zone of seismicity you can use Performance-Based Seismic Design I think very well and anywhere, like I said, U.S., Canada, maybe down even into Mexico.

JOSH CHAMOT: Great. All right. Thanks very much, John. I'd like to thank John van de Lindt from Colorado State University and our other guests as well, Hidemaru Shimizu from the E-Defense facility at Japan's National Research Institute for Earth Science and Disaster Prevention; Hiroshi Isoda, Associate Professor in the Department of Architecture and Civil Engineering at Shinshu University in Nagano, Japan; Edward Matsuyama, Director of the American Forest & Paper Association's office in Tokyo; and joining me here in the studio was Joy Pauschke. Thank-you for joining us. To learn more about what you saw today and to get some background information with additional footage and videos, you can join us at www.nsf.gov/NEESWood. The webcast will be archived there along with footage of the test. If you have additional questions, you can submit them to me at jchamot@nsf.gov. We'll get to as many as we can. If you're a reporter on deadline, let us know that in the subject line. And finally, you can come back on July 29th. My colleague, Bobby Mixon, will be hosting a webcast entitled "'Til Mortgage Do Us Part." His guests will be economists who will discuss neurological and behavioral aspects of our nation's mortgage crisis. Until then, thank you for joining us.


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