Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Simulations aiding study of earthquake dampers for structures

Researchers have demonstrated the reliability and efficiency of "real-time hybrid simulation" for testing a type of powerful damping system that might be installed in buildings and bridges to reduce structural damage and injuries during earthquakes.

The magnetorheological-fluid dampers are shock-absorbing devices containing a liquid that becomes far more viscous when a magnetic field is applied.

Earthquake-engineering researches at the Harbin Institute of Technology in China work to set up a structure on a shake table for experiments to study the effects of earthquakes. Purdue University civil engineering students are working with counterparts at the institute to study the reliability of models for testing a type of powerful damping system that might be installed in buildings and bridges to reduce structural damage and injuries during earthquakes. (Photo courtesy of Harbin Institute of Technology)

"It normally feels like a thick fluid, but when you apply a magnetic field it transforms into a peanut-butter consistency, which makes it generate larger forces when pushed through a small orifice," said Shirley Dyke, a professor of mechanical engineering and civil engineering at Purdue University.

This dramatic increase in viscosity enables the devices to exert powerful forces and to modify a building's stiffness in response to motion during an earthquake. The magnetorheological-fluid dampers, or MR dampers, have seen limited commercial use and are not yet being used routinely in structures.

Research led by Dyke and doctoral students Gaby Ou and Ali Ozdagli has now shown real-time hybrid simulations are reliable in studying the dampers. The research is affiliated with the National Science Foundation's George E. Brown Jr. Network for Earthquake Engineering Simulation (NEES), a shared network of laboratories based at Purdue.

Dyke and her students are working with researchers at the Harbin Institute of Technology in China, home to one of only a few large-scale shake-table facilities in the world.

Findings will be discussed during the NEES Quake Summit 2013 on Aug. 7-8 in Reno. A research paper also was presented in May during a meeting in Italy related to a consortium called SERIES (Seismic Engineering Research Infrastructures for European Synergies). The paper was authored by Ou, Dyke, Ozdagli, and researchers Bin Wu and Bo Li from the Harbin Institute.

"The results indicate that the real-time hybrid simulation concept can be considered as a reliable and efficient testing method," Ou said.

The simulations are referred to as hybrid because they combine computational models with data from physical tests.

"You have physical models and computational models being combined for one test," Dyke said.

Researchers are able to perform structural tests at slow speed, but testing in real-time – or the actual speed of an earthquake – sheds new light on how the MR dampers perform in structures. The real-time ability has only recently become feasible due to technological advances in computing.

"Sometimes real-time testing is necessary, and that's where we focus our efforts," said Dyke, who organized a workshop on the subject to be held during the NEES meeting in Reno. "This hybrid approach is taking off lately. People are getting very excited about it."

Ozdagli also is presenting related findings next week during the 2013 Conference of the ASCE Engineering Mechanics Institute in Evanston, Ill.

The simulations can be performed in conjunction with research using full-scale building tests. However, there are very few large-scale facilities in the world, and the testing is time-consuming and expensive.

"The real-time hybrid simulations allow you to do many tests to prepare for the one test using a full-scale facility," Dyke said. "The nice thing is that you can change the numerical model any way you want. You can make it a four-story structure one day and the next day it's a 10-story structure. You can test an unlimited number of cases with a single physical setup."

The researchers will present two abstracts during the Reno meeting. One focuses on how the simulation method has been improved and the other describes the overall validation of real-time hybrid simulations.

To prove the reliability of the approach the researchers are comparing pure computational models, pure physical shake-table tests and then the real-time hybrid simulation. Research results from this three-way comparison are demonstrating that the hybrid simulations are accurate.

Ou has developed a mathematical approach to cancel out "noise" that makes it difficult to use testing data. She combined mathematical tools for a new "integrated control strategy" for the hybrid simulation.

"She found that by integrating several techniques in the right mix you can get better performance than in prior tests," Dyke said.

The researchers have validated the simulations.

"It's a viable method that can be used by other researchers for many different purposes and in many different laboratories," Dyke said.

Much of the research is based at Purdue's Robert L. and Terry L. Bowen Laboratory for Large-Scale Civil Engineering Research and has been funded by the NSF through NEES. A portion is supported by the Sohmen Fund, an endowment established by Purdue alumnus Anna Pao Sohmen to facilitate faculty and student exchange with the Harbin Institute of Technology and Ningbo University. The fund is managed by International Programs at Purdue.

Writer: Emil Venere, (765) 494-4709,

Source: Shirley Dyke, 765-494-7434,

Note to Journalists: Information about the NEES annual Quake Summit 2013 is available at An electronic copy of the SERIES research paper is available from Emil Venere, 765-494-4709,

Emil Venere | EurekAlert!
Further information:

More articles from Architecture and Construction:

nachricht Rock solid: Carbon-reinforced concrete from Augsburg
11.10.2016 | Universität Augsburg

nachricht Heating and cooling with environmental energy
22.09.2016 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

All articles from Architecture and Construction >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>