Archives for August 2012

September Newsletter Now Available

EERI Proposes to Host 16WCEE

EERI recently submitted a first-rate bid to host the 16th World Conference on Earthquake Engineering in San Francisco in 2016.  Previously EERI hosted the 1st WCEE in Berkeley in 1956 and the 8th in San Francisco in 1984. The 16WCEE proposal is built around the theme of A New Paradigm: Earthquake Engineering for the Resilient Community and features San Francisco as a living classroom of seismic mitigation.  The proposed program includes many cutting-edge elements for sharing and learning within a traditional conference format.  Check it out, share with colleagues, spread the word, and help EERI win the bid!

The EERI proposal can be found at:

NEES-EERI Webinar on Precast Concrete Walls

“Precast Concrete Walls for Seismic Resistant-Design: From PRESSS Research to PreWEC” is the 8th in the Research to Practice Webinar Series co-produced by the Network for Earthquake Engineering Simulation (NEES) and EERI. There is no cost to attend. To register, visit PDHs will be available from EERI after the webinar for $30.

Since the Precast Seismic Structural System program (PRESSS) introduced the use of unbonded post-tensioned walls for seismic-resistant design about a decade ago, several research advancements have been made and codification has been completed. To improve cost-effectiveness and resiliency, the precast wall with end columns (PreWEC) was subsequently introduced. Today, an investigation of PreWEC—focusing on understanding the influence of various damping components and interaction between rocking walls and surrounding building components—is being conducted in the NEES Rocking Wall Project (RWP). The webinar will provide (1) a brief summary of the PRESSS wall system, (2) details of PreWEC and its performance, (3) analysis results that examined the interaction between a PreWEC system connected to floors and gravity columns, and 4) directions for implementing ongoing and completed research in design practice. In addition, an opportunity to provide input for the RWP will be provided.

Webinar presenters are Sri Sritharan, Wilson Engineering Professor at Iowa State University, Ames, Iowa, and Suzanne Dow Nakaki, a licensed structural engineer in California and the principal of Nakaki Structural Design Inc., Tustin, California. Both presenters were involved in the PRESSS program and the codification effort. Sritharan and Nakaki are, respectively, the principal investigator and consulting engineer for the ongoing RWP (

Brawley Earthquake Swarm

August 26, 2012, M5.5 Earthquake

Available Information



8/11/12 – Magnitudes 6.4 and 6.3 Earthquakes – Ahar, Iran

The U.S. Geological Survey reported the first earthquake on Saturday, August 11th was a magnitude 6.4 and struck 60 kilometers northeast of the city of Tabriz at a depth of 9.9 kilometers. The second quake, magnitude 6.3, struck 11 minutes later. Its epicenter was 50 kilometers northeast of Tabriz at a depth of 9.8 kilometers.

The first earthquake occurred at 16:53 local time, and the second occurred at 17:05, reported Mehdi Zare from the International Institute of Earthquake Engineering and Seismology (IIEES). He also reported the earthquakes occurred on the South Ahar Fault. The previous earthquake in this region occurred in 1780. As reported by Iranian television, at least twenty villages were totally destroyed in the twin earthquakes that were followed by more than 200 aftershocks with magnitudes greater than 1.0, and forty aftershocks with a magnitude greater than 3.0. Hassan Emami Razavi, Deputy Minister of Health, said 80% of the villages struck by the earthquake were damaged. Ahmad Reza Shajiei, a senior government official in charge of rescue operations, said more than 5,000 tents were set up to shelter the thousands of displaced people who spent the night outdoors.

A day after rescuers called off the search for survivors, State TV reported the death toll from Saturday’s twin earthquakes had risen to 306. The Iranian Students’ News Agency (ISNA) reported more than 5000 injured in the affected area. State TV also reported 44,000 food packages and thousands of blankets have been distributed in the stricken area. A Mehr News Agency reporter mentioned that roads in the area have been damaged, making the rescue process difficult. The Deputy Minister of Health also reported people do not have access to clean water because of broken water systems. However, to date, there have been no reports of break-outs of infectious diseases.

Bahram Akasheh, an Iranian geophysicist, seismologist and Professor of Geophysics at the University of Tehran, said these earthquakes are only 0.2 magnitude smaller than the Bam earthquake which resulted in more than 30,000 casualties. A main reason is the timing, as the Bam earthquake occurred in the morning while most everyone was asleep in their homes. These earthquakes, however, struck in the afternoon when fewer people are at home, and those that were found it easier to evacuate. He also mentioned that most buildings in this region are constructed of wood and mud, making them vulnerable to earthquakes.

Authorities say old, heavy roofs without frames were largely responsible for the high death toll in the rural areas. Interior Minister Mostafa Mohammad Najjar said the government will allocate funds to rebuild the houses destroyed in the quake, aiming to complete the construction before the arrival of cold winter temperatures. Najjar said the plans aim to construct buildings resistant to earthquakes.

View EERI’s Learning from Earthquakes Archive for reports on past earthquakes in Iran and elsewhere.


Varzaghan-Ahar, Iran

August 11, 2012, M 6.3 and 6.4 Earthquakes