Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ground Motion Study May Show Need to Modify Building Codes

06.12.2011
“In recent decades, population growth and scarcity of undeveloped metropolitan land have changed urban land use patterns and placed an increasing number of people and infrastructure in areas susceptible to topographic effects during earthquakes,” said Adrian Rodriguez-Marek, associate professor of civil and environmental engineering at Virginia Tech.

“A major impediment towards understanding and realistically modeling topographic effects has been the lack of a statistically significant number of seismic recordings from densely instrumented sites with topographic features,” Rodriguez-Marek added.

New testing conducted in a steep, mountainous region of Utah, using mining induced events, is providing a new set of data necessary for better predictions.

The testing is part of a large National Science Foundation funded project involving five institutions across the United States, with Rodriguez-Marek of Virginia Tech serving as the principal investigator. This project focuses on increasing the understanding of the effects of surface topography on earthquake ground motions and seismic risk. The goal of the project is to develop design-ready tools to account for the effect of topography on ground motions.

In addition to Virginia Tech, the University of Washington, Georgia Tech, the University of Arkansas, and the University North Carolina at Charlotte are also participants. The project uses the Network for Earthquake Engineering Simulation (NEES) equipment sites at the University of California at Davis and at the University of Texas at Austin.

The first recordings included more than 50 mining-induced seismic events. Researchers from the University of Arkansas and the University of Texas at Austin gathered this first data.

According to Rodriguez-Marek, when the study is completed, they will have the necessary information to “modify building codes and to improve safety in the building environment.”

Hillsides, ridges, and canyons are examples of sites where researchers do not have current reliable data to know how seismic shaking will be impacted by the ground features.

Although researchers have documented effects through observations of damage and the collapse of structures near the top of steep hills or ridges, “proper quantification of these effects” has not occurred because the areas did not have “densely-instrumented sites to record data,” Rodriguez-Marek explained.

The test site in Utah stood about 2000 feet above the long-wall mining activities of Deer Creek Coal Mine. The researchers placed 13, three-component sensors in a three-dimensional array over the ridge and hillside. Data was collected 24 hours a day for seven consecutive days. The 50 seismic events represented the first phase of a multi-phase project. Additional data will be gathered at the Utah site this summer, and from tests at a geotechnical centrifuge at the University of California at Davis.

“As real earthquakes are infrequent and unpredictable, the shallow and predictable seismic activity induced by the stress relief that results from long-wall mining provides a good source of seismic energy for this study,” Rodriguez-Marek said.

“Preliminary results clearly show higher ground motion intensity near the crest or peak of the slope,” he added. The early data was used to calibrate mathematical models of the effects and to design the second phase of testing that occurred in the summer of 2011. Results are still being processed.

This NSF study includes a new Bridge to the Doctorate Program geared towards increased participation and education of Hispanic students in the field of earthquake engineering.

“We hope to use our approach and collaboration among universities to serve as a model for increasing diversity in large, collaborative science, engineering, and technology research projects. Students from the University of Puerto Rico at Mayaguez have participated in summer studies at the University of Arkansas, and one student is currently enrolled at the University of North Carolina at Charlotte,” Rodriguez-Marek said.

Lynn Nystrom | Newswise Science News
Further information:
http://www.vt.edu

More articles from Studies and Analyses:

nachricht The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>