Temblor Insights: Is the San Andreas “locked, loaded, and ready to go?”

Editor’s Note: This is a republished blog post with an introduction by Jeff Ellis.

This is definitely an attention-grabbing headline! At the National Earthquake Conference in Long Beach on May 4, 2016, Dr. Thomas Jordan of the Southern California Earthquake Center gave a talk which ended with a summary statement that the San Andreas Fault is “locked, loaded and ready to go.”

The LA Times and other publications have followed up with articles based on that statement. Temblor is a mobile-friendly web app recently developed to inform homeowners of the likelihood of seismic shaking and damage based on their location and home construction. The app’s creators also offer a blog that provides insights into earthquakes and have writtene a post titled “Is the San Andreas ‘locked, loaded, and ready to go’?” This blog post delves a bit deeper to ascertain whether the San Andreas may indeed be poised for the “next great quake” and is certainly a compelling read. Drop, cover and hold on!

Volkan and I presented and exhibited Temblor at the National Earthquake Conference in Long Beach last week. Prof. Thomas Jordan, USC University Professor, William M. Keck Foundation Chair in Geological Sciences, and Director of the Southern California Earthquake Center (SCEC), gave the keynote address. Tom has not only led SCEC through fifteen years of sustained growth and achievement, but he’s also launched countless initiatives critical to earthquake science, such as the Uniform California Earthquake Rupture Forecasts (UCERF), and the international Collaboratory for Scientific Earthquake Predictability (CSEP), a rigorous independent protocol for testing earthquake forecasts and prediction hypotheses.

In his speech, Tom argued that to understand the full range and likelihood of future earthquakes and their associated shaking, we must make thousands if not millions of 3D simulations. To do this we need to use theTom Jordan portrait next generation of super-computers—because the current generation is too slow! The shaking can be dramatically amplified in sedimentary basins and when seismic waves bounce off deep layers, features absent or muted in current methods. This matters, because these probabilistic hazard assessments form the basis for building construction codes, mandatory retrofit ordinances, and quake insurance premiums. The recent Uniform California Earthquake Rupture Forecast Ver. 3 (Field et al., 2014) makes some strides in this direction. And coming on strong are earthquake simulators such as RSQsim (Dieterich and Richards-Dinger, 2010) that generate thousands of ruptures from a set of physical laws rather than assumed slip and rupture propagation. Equally important are CyberShake models (Graves et al., 2011) of individual scenario earthquakes with realistic basins and layers.

But what really caught the attention of the mediaand the public—was just one slide

Tom closed by making the argument that the San Andreas is, in his words, “locked, loaded, and ready to go.” That got our attention. And he made this case by showing one slide. Here it is, photographed by the LA Times and included in a Times article by Rong-Gong Lin II that quickly went viral.

Source: http://www.latimes.com/local/lanow/la-me-ln-san-andreas-fault-earthquake-20160504-story.html
Source: http://www.latimes.com/local/lanow/la-me-ln-san-andreas-fault-earthquake-20160504-story.html

Believe it or not, Tom was not suggesting there is a gun pointed at our heads. ’Locked’ in seismic parlance means a fault is not freely slipping; ‘loaded’ means that sufficient stress has been reached to overcome the friction that keeps it locked. Tom argued that the San Andreas system accommodates 50 mm/yr (2 in/yr) of plate motion, and so with about 5 m (16 ft) of average slip in great quakes, the fault should produce about one such event a century. Despite that, the time since the last great quake (“open intervals” in the slide) along the 1,000 km-long (600 mi) fault are all longer, and one is three times longer. This is what he means by “ready to go.” Of course, a Mw=7.7 San Andreas event did strike a little over a century ago in 1906, but Tom seemed to be arguing that we should get one quake per century along every section, or at least on the San Andreas.

Could it be this simple?

Now, if things were so obvious, we wouldn’t need supercomputers to forecast quakes. In a sense, Tom’s wake-up call contradicted—or at least short-circuited—the case he so eloquently made in the body of his talk for building a vast inventory of plausible quakes in order to divine the future. But putting that aside, is he right about the San Andreas being ready to go?

Because many misaligned, discontinuous, and bent faults accommodate the broad North America-Pacific plate boundary, the slip rate of the San Andreas is generally about half of the plate rate. Where the San Andreas is isolated and parallel to the plate motion, its slip rate is about 2/3 the plate rate, or 34 mm/yr, but where there are nearby parallel faults, such as the Hayward fault in the Bay Area or the San Jacinto in SoCal, its rate drops to about 1/3 the plate rate, or 17 mm/yr. This means that the time needed to store enough stress to trigger the next quake should not—and perhaps cannot—be uniform. So, here’s how things look to me:

The San Andreas (blue) is only the most prominent element of the 350 km (200 mi) wide plate boundary. Because ruptures do not repeat—either in their slip or their inter-event time—it’s essential to emphasize that these assessments are crude. Further, the uncertainties shown here reflect only the variation in slip rate along the fault. The rates are from Parsons et al. (2014), the 1857 and 1906 average slip are from Sieh (1978) and Song et al. (2008) respectively. The 1812 slip is a model by Lozos (2016), and the 1690 slip is simply a default estimate.
The San Andreas (blue) is only the most prominent element of the 350 km (200 mi) wide plate boundary. Because ruptures do not repeat—either in their slip or their inter-event time—it’s essential to emphasize that these assessments are crude. Further, the uncertainties shown here reflect only the variation in slip rate along the fault. The rates are from Parsons et al. (2014), the 1857 and 1906 average slip are from Sieh (1978) and Song et al. (2008) respectively. The 1812 slip is a model by Lozos (2016), and the 1690 slip is simply a default estimate.

So, how about ‘locked, generally loaded, with some sections perhaps ready to go’

When I repeat Tom’s assessment in the accompanying map and table, I get a more nuanced answer. Even though the time since the last great quake along the southernmost San Andreas is longest, the slip rate there is lowest, and so this section may or may not have accumulated sufficient stress to rupture. And if it were ready to go, why didn’t it rupture in 2010, when the surface waves of the Mw=7.2 El Major-Cucapah quake just across the Mexican border enveloped and jostled that section? The strongest case can be made for a large quakeNicolas Ambraseysoverlapping the site of the Great 1857 Mw=7.8 Ft. Teton quake, largely because of the uniformly high San Andreas slip rate there. But this section undergoes a 40° bend (near the ‘1857’ in the map), which means that the stresses cannot be everywhere optimally aligned for failure: it is “locked” not just by friction but by geometry.

A reality check from Turkey

Sometimes simplicity is a tantalizing mirage, so it’s useful to look at the San Andreas’ twin sister in Turkey: the North Anatolian fault. Both right-lateral faults have about the same slip rate, length, straightness, and range of quake sizes; they both even have a creeping section near their midpoint. But the masterful work of Nicolas Ambraseys, who devoured contemporary historical accounts along the spice and trade routes of Anatolia to glean the record of great quakes (Nick could read 14 languages!) affords us a much longer look than we have of the San Andreas.

The idea that the duration of the open interval can foretell what will happen next loses its luster on the North Anatolian fault because it’s inter-event times, as well as the quake sizes and locations, are so variable. If this 50% variability applied to the San Andreas, no sections could be fairly described as ‘overdue’ today. Tom did not use this term, but others have. We should, then, reserve ‘overdue’ for an open interval more than twice the expected inter-event time.

This figure of North Anatolian fault quakes is from Stein et al. (1997), updated for the 1999 Mw=7.6 Izmit quake, with the white arrows giving the direction of cascading quakes. Even though 1939-1999 saw nearly the entire 1,000 km long fault rupture in a largely western falling-domino sequence, the earlier record is quite different. When we examined the inter-event times (the time between quakes at each point along the fault), we found it to be 450±220 years. Not only was the variation great—50% of the time between quakes—but the propagation direction was also variable.
This figure of North Anatolian fault quakes is from Stein et al. (1997), updated for the 1999 Mw=7.6 Izmit quake, with the white arrows giving the direction of cascading quakes. Even though 1939-1999 saw nearly the entire 1,000 km long fault rupture in a largely western falling-domino sequence, the earlier record is quite different. When we examined the inter-event times (the time between quakes at each point along the fault), we found it to be 450±220 years. Not only was the variation great—50% of the time between quakes—but the propagation direction was also variable.

However, another San Andreas look-alike, the Alpine Fault in New Zealand, has a record of more regular earthquakes, with an inter-event variability of 33% for the past 24 prehistoric quakes (Berryman et al., 2012). But the Alpine fault is straighter and more isolated than the San Andreas and North Anatolian faults, and so earthquakes on adjacent faults do not add or subtract stress from it. And even though the 31 mm/yr slip rate on the southern Alpine Fault is similar to the San Andreas, the mean inter-event time on the Alpine is longer than any of the San Andreas’ open intervals: 330 years. So, while it’s fascinating that there is a ‘metronome fault’ out there, the Alpine is probably not a good guidepost for the San Andreas.

If Tom’s slide is too simple, and mine is too equivocal, what’s the right answer?

I believe the best available answer is furnished by the latest California rupture model, UCERF3. Rather than looking only at the four San Andreas events, the team created hundreds of thousands of physically plausible ruptures on all 2,000 or so known faults. They found that the mean time between Mw≥7.7 shocks in California is about 106 years (they report an annual frequency of 9.4 x 10^-3 in Table 13 of Field et al., 2014; Mw=7.7 is about the size of the 1906 quake; 1857 was probably a Mw=7.8, and 1812 was probably Mw=7.5). In fact, this 106-year interval might even be the origin of Tom’s ‘once per century’ expectation since he is a UCERF3 author.

But these large events need not strike on the San Andreas, let alone on specific San Andreas sections, and there are a dozen faults capable of firing off quakes of this size in the state. While the probability is higher on the San Andreas than off, in 1872 we had a Mw=7.5-7.7 on the Owen’s Valley fault (Beanland and Clark, 1994). In the 200 years of historic records, the state has experienced up to three Mw≥7.7 events, in southern (1857) and eastern (1872), and northern (1906) California. This rate is consistent with, or perhaps even a little higher than, the long-term model average.

So, what’s the message

While the southern San Andreas is a likely candidate for the next great quake, ‘overdue’ would be over-reach, and there are many other fault sections that could rupture. But since the mean time between Mw≥7.7 California shocks is about 106 years, and we are 110 years downstream from the last one, we should all be prepared—even if we cannot be forewarned.

Ross Stein (ross@temblor.net), Temblor

You can check your home’s seismic risk at Temblor

References cited:

Sarah Beanland and Malcolm M. Clark (1994), The Owens Valley fault zone, eastern California, and surface faulting associated with the 1872 earthquake, U.S. Geol. Surv. Bulletin 1982, 29 p.

Kelvin R. Berryman, Ursula A. Cochran, Kate J. Clark, Glenn P. Biasi, Robert M. Langridge, Pilar Villamor (2012), Major Earthquakes Occur Regularly on an Isolated Plate Boundary Fault, Science, 336, 1690-1693, DOI: 10.1126/science.1218959

James H. Dietrich and Keith Richards-Dinger (2010), Earthquake recurrence in simulated fault systems, Pure Appl. Geophysics, 167, 1087-1104, DOI: 10.1007/s00024-010-0094-0.

Edward H. (Ned) Field, R. J. Arrowsmith, G. P. Biasi, P. Bird, T. E. Dawson, K. R., Felzer, D. D. Jackson, J. M. Johnson, T. H. Jordan, C. Madden, et al.(2014). Uniform California earthquake rupture forecast, version 3 (UCERF3)—The time-independent model, Bull. Seismol. Soc. Am. 104, 1122–1180, doi: 10.1785/0120130164.

Robert Graves, Thomas H. Jordan, Scott Callaghan, Ewa Deelman, Edward Field, Gideon Juve, Carl Kesselman, Philip Maechling, Gaurang Mehta, Kevin Milner, David Okaya, Patrick Small, Karan Vahi (2011), CyberShake: A Physics-Based Seismic Hazard Model for Southern California, Pure Appl. Geophysics, 168, 367-381, DOI: 10.1007/s00024-010-0161-6.

Julian C. Lozos (2016), A case for historical joint rupture of the San Andreas and San Jacinto faults, Science Advances, 2, doi: 10.1126/sciadv.1500621.

Tom Parsons, K. M. Johnson, P. Bird, J.M. Bormann, T.E. Dawson, E.H. Field, W.C. Hammond, T.A. Herring, R. McCarey, Z.-K. Shen, W.R. Thatcher, R.J. Weldon II, and Y. Zeng, Appendix C—Deformation models for UCERF3, USGS Open-File Rep. 2013–1165, 66 pp.

Seok Goo Song, Gregory C. Beroza and Paul Segall (2008), A Unified Source Model for the 1906 San Francisco Earthquake, Bull. Seismol. Soc. Amer., 98, 823-831, doi: 10.1785/0120060402

Kerry E. Sieh (1978), Slip along the San Andreas fault associated with the great 1857 earthquake, Bull. Seismol. Soc. Am., 68, 1421-1448.

Ross S. Stein, Aykut A. Barka, and James H. Dieterich (1997), Progressive failure on the North Anatolian fault since 1939 by earthquake stress triggering, Geophys. J. Int., 128, 594-604, 1997, 10.1111/j.1365-246X.1997.tb05321.x

Great ShakeOut Earthquake Drill

They say you never forget your first love. Well, I remember my first earthquake, too. My elementary school had earthquake and fire drills often, but the Livermore Earthquake in January, 1980 was the first time we had to drop and cover during an actual earthquake. The earthquake occurred along the Greenville fault and over 20 years later, I was the project engineer for an event center not far from this fault. I don’t think that earthquake that led me on the path to become a structural engineer. I was only seven and was more focused on basketball and Atari games than future fields of study.

My favorite part about the Livermore Earthquake was the 9-day sleepover we managed to negotiate with my parents. I have a big family, so we had a large, sturdy dinner table. My brother Neil and I convinced my parents it would be better if we slept under the table, in case there was an aftershock. And, of course, we should invite our friends, the Stevensons, to sleepover because they don’t have as large a dinner table to sleep under at their house. And it worked! In our defense, there were a lot of aftershocks and an additional earthquake a few days later.

Each year, an earthquake preparedness event known as the Great ShakeOut Earthquake Drill takes place around the globe. The event provides an opportunity for people in homes, schools, businesses and other organizations to practice what to do during earthquakes.

Simpson Strong-Tie is helping increase awareness about earthquake safety and encouraging our customers to participate in the Great ShakeOut, which takes place next Thursday on October 15. It’s the largest earthquake drill in the world. More than 39 million people around the world have already registered on the site.

We’re also providing resources on how to retrofit homes and buildings, and have information for engineers at strongtie.com/softstory and for homeowners at safestronghome.com/earthquake.

Earthquake risk is not just a California issue. According to the USGS, structures in 42 of 50 states are at risk for seismic damage. As many of you know, we have done a considerable amount of earthquake research, and are committed to helping our customers build safer, stronger homes and buildings. We continue to conduct extensive testing at our state-of-the-art Tye Gilb lab in Stockton, California, and next Wednesday, we’ll be performing a multi-story wall shake table test for a group of building officials at our lab. We are also working with the City of San Francisco to offer education and retrofit solutions to address their mandatory soft-story building retrofit ordinance and have created a section on our website to give building owners and engineers information to help them meet the requirements of the ordinance.

Soft Story Building with seismic damage.

Seismic damage to a soft-story building in San Francisco.

Our research is often in conjunction with academia. In 2009, we partnered with Colorado State University to help lead the world’s largest earthquake shake table test in Japan, demonstrating that mid-rise wood-frame buildings can be designed and built to withstand major earthquakes.

Earthquake articles like the one from The New Yorker also remind us how important it is to retrofit homes and buildings and to make sure homes, businesses, families and coworkers are prepared.

Like others in our industry, structural engineers play a role in increasing awareness about earthquake safety. We’d like to hear your thoughts about designing and retrofitting buildings to be earthquake resilient. Let us know in the comments below. And if your office hasn’t signed up for the Great ShakeOut Earthquake Drill, we encourage you to do so by visiting shakeout.org.

Seismic Safety Regulations and Solutions

I have a special place in my heart for old buildings. Every college design course I took was related to new design. Concrete, steel, or wood design, the design problem was invariably part of a new building. I thought structural engineers designed new buildings. When I showed up for my first day of work wearing dress pants, a button-down shirt and a tie, I was handed a flashlight, tape measure, a clipboard and a Thomas Guide map (no Google maps back then) and sent to do as-built drawings for a concrete tilt-up that we were retrofitting.

When I was designing buildings, I created a lot of as-built drawings. Figuring out how a building was put together, what the structural system was (or wasn’t!) and designing a lateral load path in these old, and often historic buildings, was immensely satisfying. Knowing that history, it should not be surprising I have done a number of blog posts related to seismic retrofits. Soft-Story Retrofits, San Francisco’s Soft-Story Retrofit Ordinance, Remembering Loma Prieta, Resilient Communities, FEMA P-807, and Home Seismic Retrofit (there are probably a couple I forgot).

This week, Los Angeles Mayor Eric Garcetti proposed new seismic safety regulations . The recommendations are to retrofit soft-story wood-framed buildings within five years and older concrete buildings within 30 years. While these are only recommendations, it is encouraging to see politicians supporting policies to promote resiliency and life safety.

In San Francisco, thousands of building owners are already required by law to seismically retrofit multi-unit (at least five) soft-story, wood-frame residential structures that have two or more stories over a “soft” or “weak” story. These buildings typically have parking or commercial space on the ground floor with two or more stories above. As a result, the first floor has far more open areas of the wall than it actually has sheathed areas, making it particularly vulnerable to collapse in an earthquake.

Soft story building damaged by an earthquake

Photo credit: J.K. Nakata and the U.S. Geological Survey

San Francisco’s ordinance affects buildings permitted for construction before Jan. 1, 1978. Mandatory seismic retrofit program notices requiring that buildings be screened were sent out in September, 2013, to more than 6,000 property owners. It is anticipated that approximately 4,000 of those buildings will be required to be retrofitted by 2020.

“When we look at the demographic of these buildings, they house approximately 110,000 San Franciscans. It’s paramount that we have housing for people after a disaster. We know we will see issues in all types of buildings, but this is an opportunity for us to be able to retrofit these buildings while keeping an estimated 1100,000 San Franciscans in their homes and, by the way of retrofit, allowing them to shelter in place after a disaster,” according to Patrick Otellini, San Francisco’s chief resilience officer and director of the city’s Earthquake Safety Implementation Program. “This exponentially kick starts the city’s recovery process.”

One solution to strengthen such buildings is the Simpson Strong-Tie® Strong Frame® special moment frame. Its patented Yield-Link™ structural fuses are designed to bear the brunt of lateral forces during an earthquake, isolating damage within the frame and keeping the structural integrity of the beams and columns intact.

Simpson Strong-Tie® Strong Frame® special moment frame

Simpson Strong-Tie® Strong Frame® special moment frame

“The structural fuses connect the beams to the columns. These fuses are designed to stretch and yield when the beam twists against the column, rather than the beam itself, and because of this the beams can be designed without bracing. This allows the Strong Frame to become a part of the wood building and perform in the way it’s supposed to,” said Steve Pryor, S.E., International Director of Building Systems at Simpson Strong-Tie. “It’s also the only commercially-available frame that bolts together and has the type of ductile capacity that can work inside of a wood-frame building.”

Installation of the Simpson Strong-Tie® Strong Frame® special moment frame

Installation of the Simpson Strong-Tie® Strong Frame® special moment frame

Another key advantage of the Simpson Strong-Tie special moment frame is no field welding is required, which eliminates the risk of fire in San Francisco’s older wood-framed buildings.

To learn more about San Francisco’s retrofit ordinance, watch a new video posted on strongtie.com/softstory. For more information about the Strong Frame special moment frame, visit strongtie.com/strongframe.

Remembering Loma Prieta

Steve Pryor

Structural engineer Steve Pryor in the Simpson Strong-Tie Tye Gilb lab.

Steve Pryor, S.E., has been with Simpson Strong-Tie for 17 years and currently serves as the International Director of Building Systems. Prior to joining the company, Mr. Pryor was a practicing structural engineer in California. While at Simpson Strong-Tie, he developed the Tyrell T. Gilb Research Laboratory, one of the world’s premier large-scale structural systems test facilities. The lab has the capability to simulate both wind and seismic effects on light-frame structures via both quasi static/cyclic and dynamic test machines that can apply vertical and lateral loading simultaneously. A recognized expert in the structural response, analysis and testing of light-frame buildings, Mr. Pryor participates on several state and national building code committees. He was the primary industry technical consultant for the highly successful NEESWood Capstone seismic testing in Miki, Japan, which tested a full-scale seven-story mixed-use steel/wood structure, the largest building ever tested on a shake table.

We all know that earthquakes physically shape the landscape here in California, but they shape careers as well.  Earthquakes I felt while growing up in California’s southern San Joaquin Valley got me thinking about engineering as a career while in high school. When the Loma Prieta earthquake struck on October 17, 1989, like many of you I was watching the World Series live on television and thus got to see the earthquake live as well. I was in my senior year of college at the time, studying Civil Engineering with a structural emphasis. This earthquake cemented the direction I would take in my career. I wanted to be a structural engineer, and I wanted to design buildings that would not fall down in earthquakes.

After Loma Prieta hit, I was relieved when I finally got through to my family and realized everyone was okay.  If an earthquake like that happened again today, I would get an alert on my cell phone and know within minutes exactly where it happened, how big it was, and how deep it was. I would also be able to look at the USGS ShakeMap online to get a feel of ground-level damage potential and locations. But in 1989, none of this information was available so over the course of the next few days along with the public, I learned about what had happened in the Bay Area.

After graduating in 1990, several great mentors guided me as I pursued the art of earthquake-resistant structural engineering. I began to realize that earthquakes are like a great predator of the built environment: occasionally they take down healthy buildings in their prime, but they particularly focus on the old and the weak amongst our building stock; buildings with known (and sometimes unknown) deficiencies that if improperly designed or left unretrofitted cause them to fall prey to the earthquake.   After several years of practicing structural engineering, and after obtaining my P.E. and S.E., it was with some irony that I came to work at Simpson Strong-Tie in 1997. I became part of a team of dedicated people working to provide structural solutions to new and existing buildings in an effort to keep them from falling prey to the next earthquake. I was now a Bay Area resident, living in the shadows of the same seismic hazards that had manifest themselves on October 17, 1989, and which had shaped my career choice.

While there were many different types of structural weakness on display as a result of the Loma Prieta earthquake, soft- or weak-story wood-frame structures commanded much of the attention. These multi-story wood light-frame structures have an inherent weakness at the ground floor because the area open for parking also cuts down on the area available for shear walls, and thus the available lateral strength. Without the requisite lateral strength in these weak stories, many buildings suffered heavy damage and even collapse. And all of this from an earthquake that was centered about 56 miles south of San Francisco.  One can only imagine what would happen if a similar earthquake occurred much closer.

In response to this threat, the City of San Francisco has embarked on a groundbreaking mandatory retrofit ordinance that will hopefully allow many of the city’s residents who live in these structures to “shelter in place” after the next “big one.” What buildings are affected by this ordinance? Wood-frame buildings built or permitted prior to January 1, 1978 with two or more stories over a soft- or weak-story that contain five or more dwelling units.

There are many questions that automatically pop up in response to this. How well does my building have to perform in order to enable me to shelter in place? Could I possibly shelter in place with a yellow tag on my building, or does it have to be green tagged? There is debate on this issue. What constitutes the “big one” – is it the “expected” more frequent earthquake, or is it the extremely rare, very large earthquake? The engineering criteria of the retrofit ordinance points toward it being the “expected” earthquake. Can these retrofits be done (economically) and will they make a difference?  Absolutely. How can you say that? We’ve tested them.

Simpson Strong-Tie was a proud sponsor and contributor to an ambitious project known as NEES-Soft. Led by Dr. John W. van de Lindt of Colorado State University, the project culminated with shake table testing of a full-scale four-story weak-story building on the outdoor shake table at the University of California San Diego in the summer of 2013. Constructed to be like a real San Francisco weak-story structure, the building offered a fantastic platform to test various retrofit technologies. One of the retrofit technologies tested was the Simpson Strong-Tie Strong Frame® special moment frame. Designed according to one of the engineering approaches (FEMA P-807) permitted in the City of San Francisco’s retrofit ordinance, the Strong Frame special moment frame performed extremely well, and we were able to conclusively demonstrate the improved performance of the building. Check out this link to understand some of the unique features that make this frame especially well suited for seismic retrofits of wood-frame structures. And don’t forget that any retrofit frame or wall is only one part of the complete load path needed for a successful retrofit!

The Strong Frame special moment frame did not materialize overnight in response to the new retrofit ordinance. The work on it and the other lateral force resisting products we manufacture began years earlier. It turns out that there are a whole bunch of people at our company, professional engineer or not, who are constantly thinking about this and share the same desire that developed in me back in 1989: let’s make products that help buildings not fall down in earthquakes. How can we help you on your project?  Let us know – we’d love to hear from you.