DesignSafe Radio

Host Dan Zehner meets up with geotechnical engineer Brady Cox, professor of engineering at Utah State University and co-PI at the NHERI @ University of Texas mobile shaker facility. Cox introduces the UTexas mobile shakers, huge vehicles that simulate a range of ground motions for studying earthquakes. There’s “T-Rex,” perhaps the world’s only shaker capable of generating large dynamic forces in any of three directions — vertical, horizontal in-line, and horizontal cross-line. And the custom-built “Liquidator,” weighing in at 70,000 pounds, which shakes vertically at very low frequencies; its longer waves help researchers look deeper into the ground. 

Cox describes how engineers deploy the NHERI mobile shaker fleet around the world to study ground-based infrastructure like levees, soils that are prone to liquefaction, and civil structures like bridges.

Natural hazards engineers at the University of Texas are using fiber optic cable for subsurface and structural sensing. It’s called distributed acoustic sensing, or DAS, and it is much more efficient than traditional geophones or accelerometers. By sending laser light pulses through fiber optic cables — which are ultra-sensitive to light deflections — researchers can measure ground disturbances for up to 30 meters.

NHERI at UTexas website: https://utexas.designsafe-ci.org/

Short video shows how a shaker truck is used to characterize soil: https://www.youtube.com/watch?v=5cGbMggwxog

More about Brady Cox’s research: https://engineering.usu.edu/cee/people/faculty/cox-brady

Subsurface geotechnical imaging, as with levees: 

https://www.youtube.com/watch?v=IS-qn06pVOw&list=PL2GxvrdFrBlma1A6IMfMasP-RP8ku5s2N&index=1

Testing for liquefiable soils:

https://www.youtube.com/watch?v=5cGbMggwxog&list=PL2GxvrdFrBlma1A6IMfMasP-RP8ku5s2N&index=2

Structural health monitoring:

https://www.youtube.com/watch?v=HRX-WMumpDQ&list=PL2GxvrdFrBlma1A6IMfMasP-RP8ku5s2N&index=3

NHERI at UTexas recently presented a workshop on DAS technology, including a live demonstration of a levee in Blackhawk, Louisiana.  View the workshop recordings here.

Interested in using NHERI Mobile Shakers in your work, or want to learn more? Contact us! 

Natural hazards engineers at the University of Texas are using fiber optic cable for subsurface and structural sensing. It’s called distributed acoustic sensing, or DAS, and it is much more efficient than traditional geophones or accelerometers. By sending laser light pulses through fiber optic cables — which are ultra-sensitive to light deflections — researchers can measure ground disturbances for up to 30 meters. 

Sound interesting? Contact the NSF-funded NHERI network to learn more: [email protected].

NHERI at UTexas recently presented a workshop on DAS technology, including a live demonstration of a levee in Blackhawk, Louisiana. View the workshop recordings here. 

Here is natural hazards research that takes place outside the lab! Professor Brady Cox describes how engineers deploy the NHERI mobile shaker fleet around the world to study ground-based infrastructure like levees, soils that are prone to liquefaction, and civil structures like bridges. 

Watch Brady Cox’s demonstration videos here:

Subsurface geotechnical imaging, as with levees: click here 

Testing for liquefiable soils: https://www.youtube.com/watch?v=5cGbMggwxog&list=PL2GxvrdFrBlma1A6IMfMasP-RP8ku5s2N&index=2

Structural health monitoring: https://www.youtube.com/watch?v=HRX-WMumpDQ&list=PL2GxvrdFrBlma1A6IMfMasP-RP8ku5s2N&index=3

Interested in using NHERI Mobile Shakers in your work, or want to learn more? Contact us!

On today’s show, we get an intro to the mobile shaker fleet at the NHERI’s University of Texas facility. Host Dan Zehner meets up with geotechnical engineer Brady Cox, professor of engineering at Utah State University and co-PI at the NHERI @ University of Texas mobile shaker facility. Cox introduces the UTexas mobile shakers, huge vehicles that simulate a range of ground motions for studying earthquakes. There’s “T-Rex,” perhaps the world’s only shaker capable of generating large dynamic forces in any of three directions — vertical, horizontal in-line, and horizontal cross-line. And the custom-built “Liquidator,” weighing in at 70,000 pounds, which shakes vertically at very low frequencies; its longer waves help researchers look deeper into the ground. 

NHERI at UTexas website: https://utexas.designsafe-ci.org/

Short video shows how a shaker truck is used to characterize soil: https://www.youtube.com/watch?v=5cGbMggwxog

More about Brady Cox’s research: https://engineering.usu.edu/cee/people/faculty/cox-brady

In this episode of DesignSafe Radio, structural engineer Elaina Sutley covers ways that research can tangibly improve resilience of manufactured homes. She discusses local amendments to building codes that cities can implement. Currently, she and her research team are studying mobile home parks and ways to reduce wind damage. She emphasizes that dealing with windstorms is more than a building design problem, since residents in these vulnerable structures are often the most socially vulnerable. We also need systems in place to help people recover from natural disasters.

Elaina Sutley’s research group at University of Kansas, Advancing Disaster Resilience Science on Communities and Housing.Wind damage data collected by Sutley and other natural hazards researchers is available at the DesignSafe Data Depot repository.

Sutley explains differences between manufactured homes and site-built homes and why there is so little crossover in design provisions. She also refutes the primary objection to improving performance manufactured homes: If we improve performance, they won’t be affordable.

Additionally, Sutley describes how researchers can use publicly available data to deepen their wind disaster investigations when alongside damage data gathered onsite.

It’s no secret: tornadoes and hurricanes wreak havoc on manufactured homes. So why don’t we build them stronger? To detail the challenges to improving their performance we have Elaina Sutley, associate professor of structural engineering at the University of Kansas. With an interdisciplinary engineering and social science focus, Sutley examines disparities when it comes to communities recovering from extreme wind hazards.

Although the problem is well-known, change is slow. Sutley details the particular problems and complexities involved in upgrading design provisions for manufactured homes.

For more information:

Contact Elaina Sutley 

Engineers Who Engage: Elaina Sutley 

Wind Effects on Elevated Buildings 

If you have not been able to catch our most recent episodes with Jason DeJong, listen to this episode for his full interview. Jason DeJong is a professor of engineering at UC Davis and is the head of the Center for Biomediated and Bioinspired Geotechnics (CBBG) team at UC Davis. 

• More information on NHERI at UC Davis
• Jason DeJong 

“That proportional scale is amazing. We can simulate real-world systems that we can’t really do any other way.” - Jason DeJong

Snake skin, tree roots, and nitrogen-burping microbes! In our third episode on biogeotechnics, Jason DeJong discusses a few of the wild-sounding research projects that focus on imitating or controlling natural processes — to create safer, and more efficient, infrastructure.

Researchers develop ideas the Center for Biomediated and Bioinspired Geotechnics (CBBG), and they can test theirconcepts at places like NHERI at UC Davis and at otherfacilities in the NSF-funded Natural Hazards Engineering Research Infrastructure (NHERI). Both NHERI and CBBG are funded by the National Science Foundation, demonstrating the nation’s commitment to fostering and deploying emerging new designs and technologies in bioengineering.

“It’s a nice combination. We have technologies emerging from one group, and we have these established, shared-use national resources provided through NHERI.”