What is the risk to high-rise buildings from such a giant earthquake? Although four giant subduction earthquakes occurred elsewhere in the past century, there were no cities with high-rise buildings in the heavily shaken areas for any of these events. Furthermore, ground motions have never been recorded in areas strongly shaken by a giant earthquake.
T. Heaton and J. Yang of Caltech simulated ground shaking from an earthquake similar to the giant Sumatran earthquake (M 9.2) that occurred in 2004, and which is hypothesized to be similar to the giant earthquakes in the Pacific Northwest. The simulated shaking lasts for more than four minutes and it is dominated by low frequency motions. While smaller buildings (e.g., wooden houses) are not particularly susceptible to these low frequency motions, tall buildings resonate at the low frequencies contained in these simulations. The Seattle basin exacerbates the situation by significantly amplifying these long-period motions in the Seattle metropolitan area. Heaton and Yang simulated the response of modern steel 6- and 20-story buildings to the hypothetical ground motions. Although there are many unanswered questions about such a future earthquake, they report that severe damage and possible collapse is indicated in many of their simulations.
Buildings that were constructed prior to important building code changes that were made as a result of the 1994 Northridge earthquake are especially vulnerable to this long period shaking. Heaton and Yang report that, given the current state of understanding, there is insufficient knowledge of ground shaking and of building response to ensure the integrity of tall buildings in such an earthquake.
SSA is a scientific society devoted to the advancement of earthquake science. Founded in 1906 in San Francisco, the Society now has members throughout the world representing a variety of technical interests: seismologists and other geophysicists, geologists, engineers, insurers, and policy-makers in preparedness and safety.
Nan Broadbent | EurekAlert!
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Cyclic change within magma reservoirs significantly affects the explosivity of volcanic eruptions
30.11.2016 | Johannes Gutenberg-Universität Mainz
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy