ORIGINAL_ARTICLE
Investigation on the Potential of OSL for Dating Qanat in the Dasht-e Bayaz Region of Northeastern Iran Using the SAR Protocol for Quartz
In some parts of Iran, such as Dasht-e-Bayaz, the line of wells of the Qanat systems have been displaced by coseismic faulting. If we can date the age of these Qanat wells and measure the amount of offset, we will be able to estimate the slip-rate of the fault. The existing constraints on age of ancient Qanats in Iran are typically assigned from archaeological investigations of nearby habitation sites. We present for the first time the results of OSL dating from spoil deposits associated with the Dasht-e-Bayaz Qanat. We further explore the possibility of dating Qanat directly using the novel method of OSL. The minimum ages which are assigned to maintenance and construction of Dasht-e-Bayaz Qanat, using SAR protocol are 15.8±1.6ka and 22.1±2.7ka, respectively. Archeological investigations suggest that the Qanat ages are much younger than ages obtained by OSL. We present evidence that the SAR approach that we have chosen is operative but not relevant. The OSL method has provided ages that are consistent with stratigraphic layers in the well, but these layers were not fully bleached during construction. The single aliquot method to which dim samples we've applied in the recent research is not an efficacious way to achieve the age of Qanats and may need to test for more samples.
http://www.jsee.ir/article_240621_2d4f84a57ed476e1285020fb76e15701.pdf
2011-07-01
65
75
Qanat
OSL Dating
Dasht-e-Bayaz Fault
SAR
M.
Fattahi
morteza.fattahi@ouce.ox.ac.uk
1
Oxford University Center for the Environment
LEAD_AUTHOR
A.
Aqazadeh
2
Institute of Geophysics, University of Tehran
AUTHOR
R.T.
Walker
3
University of Oxford
AUTHOR
M.
Talebian
4
Geological Survey of Iran, Tehran
AUTHOR
R.A.
Sloan
5
University of Cambridge
AUTHOR
M.M.
Khatib
6
Birjand University
AUTHOR
ORIGINAL_ARTICLE
Seismic Behavior of 63kV and 132kV Substation Post Insulators with Flexible Conductors, an Experimental Approach
Recent Earthquakes have shown that the electrical substations are very vulnerable, and direct and indirect losses resulting from their damages are highly considerable. Post insulators in high-voltage substations are usually used as support for the bus bars or flexible conductors. Due to their height, low lateral stiffness and brittle materials used for the main core of such component, they have shown very poor seismic performance. In this paper, the seismic behavior of two 63kV and 132kV PIs with flexible connections to their top is studied experimentally. Tests samples consist of individual post insulators mounted directly on the simulator platform followed by tests of complete post insulators mounted on the lattice steel structure as the support. Insulators were subjected to two different sets of inputs, first a set of sine sweeps and the second set was earthquake simulations time histories. The results of the experiments were used to verify the numerical models for further complementary assessments. The results show that they have very high frequencies and hardly can get damaged due to resonance, but the lattice steel structure decreased the natural frequencies by almost 70%, which amplifies the acceleration by %25.
http://www.jsee.ir/article_240622_a179076b33481b08da0bca85992a6a7f.pdf
2011-07-01
77
92
Substation
Seismic Behavior
Post Insulator
Shake Table Test
A.H.
Khalvati
ah.khalvati@iiees.ac.ir
1
IIEES
LEAD_AUTHOR
M.
Hosseini
2
IIEES
AUTHOR
S.
Mohammadpour
3
Azad Islamic University
AUTHOR
ORIGINAL_ARTICLE
Resilience Against Earthquakes: Some Practical Suggestions for Planners and Managers
This paper offers a working definition of resilience and associated concepts, including vulnerability to earthquakes, coping, capacity and redundancy. It concludes that resilience must be set in motion and maintained by a collective effort that involves all stakeholders and people who are at risk. The paper offers ten suggestions for action in order to create a methodology for resilience against earthquakes. They are as follows. Tell people what to do in an earthquake. Develop urban search and rescue capacity on site. Reduce non-structural as well as structural hazards. Plan flexibly and make emergency planning a process, not an end. Create networks that can improve the exchange of knowledge, information and training. Encourage governance by involving different stakeholders in earthquake disaster risk reduction. Make good practice proliferate and adapt it to local circumstances. Ensure that programmes of disaster risk reduction are sustainable in the long term. Before the next major seismic event occurs, create a strategy for recovering from it. Create a culture of resilience against earthquakes, in which the problem is widely understood and taken seriously by people who are at risk or are in positions of authority.
http://www.jsee.ir/article_240619_3ce83b415f0f205b97b7a7c382147a62.pdf
2011-07-01
109
115
Earthquakes
resilience
disasters
Injury Prevention
Damage Reduction
D.
Alexander
david.alexander@grforum.org
1
Chief Senior Scientist, Global Risk Forum
LEAD_AUTHOR
ORIGINAL_ARTICLE
Experimental and Analytical Investigation on In-Plane Behavior of URM Flanged Walls
The shape of most of the wall sections in existing unreinforced masonry (URM) structures have L, T, and H shapes, instead of rectangle. Limited research on the effect of return wall (flange) on their seismic behavior has been reported in the literature. The primary aim of this study is to develop a deeper understanding of in-plane response of URM walls with emphasis on return walls. The URM shear walls represent existing masonry structures with poor shear strength. An Experimental program has been conducted on four specimens with aspect ratios of 0.5 and 0.7. Two specimens designed with flanges and, for comparison, another two specimens designed without flanges. All specimens tested under constant axial force corresponding to typical 3-story buildings, and cyclic reversal displacement control loading was applied in horizontal direction. Predicted shear strength based on FEMA-356 has been compared with experimental results. An analytical model has been proposed to predict lateral response of flanged URM walls. The results emphasize on the effect of flanges when seismic assessment of non-rectangular section URM walls is considered.
http://www.jsee.ir/article_240623_9b78fe6f904139ae654ed630a8b0592c.pdf
2011-07-01
93
108
Unreinforced Masonry
Return Wall (Flange)
Shear strength
experimental
Analytical Model
M.
Khanmohammadi
mkhan@ut.ac.ir
1
College of Engineering, University of Tehran
LEAD_AUTHOR
H.
Behnam
2
College of Engineering, University of Tehran
AUTHOR
M.S.
Marefat
3
College of Engineering, University of Tehran
AUTHOR
ORIGINAL_ARTICLE
Seismic Risk Analysis of Metropolitan Tehran: A Link Between Hazard Analysis, Vulnerability Assessment and Loss Estimation Studies
Metropolitan Tehran, as the capital, the economic and political center, and the most populated city in Iran, has a special position in earthquake preparation, mitigation and response. Tehran is vulnerable to earthquakes and is expecting a destructive earthquake with a magnitude greater than 7. In the present paper, the items of hazard analysis, vulnerability assessment, and loss estimation in respect of Tehran are introduced, and the relevant research concerning the category of physical and structural damage is investigated. The results from vulnerability assessment indicate the vulnerability of a major part of the buildings in Tehran. The results from the loss estimation indicate a high percentage of damage in the event of an earthquake in Tehran. Furthermore, based on the loss estimation results, the likely amount of debris generated and possibilities for positioning of the temporary housing are provided. The results emphasize the necessity of short-term, average-term and long-term policies for damage reduction and seismic reinforcement.
http://www.jsee.ir/article_240620_219862a80d8fbe57662bca5540dfe0ee.pdf
2011-07-01
117
137
Earthquake
Tehran
Risk Analysis
Loss estimation
Vulnerability assessment
Debris
Temporary Shelter
B.
Omidvar
bomidvar@ut.ac.ir
1
Faculty of Environment, University of Tehran
LEAD_AUTHOR
S.
Tavakoli
2
Faculty of Environment, University of Tehran
AUTHOR
M.
Eskandari
3
Faculty of Environment, University of Tehran
AUTHOR