• Steel and Composite Structures
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• v.17 no.5
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• pp.687-704
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• 2014

A great number of moment-resisting steel structures collapsed due to ductile crack initiation at welded beam-column connections, followed by explosive brittle fracture in the Kobe (Hyogoken-Nanbu) earthquake in 1995. A series of experimental and numerical studies on cracking behaviors of beam-column connections in steel bridge piers were carried out by the authors' team. This paper aims to study the effect of post weld treatment on cracking behaviors of the connections during a strong earthquake event. Experiments of three specimens with different weld finishes, i.e., as-welded, R-finish, and burr grinding, were conducted. The experimental results indicate that the instants of ductile crack initiation are greatly delayed for the specimens with R-finish and burr grinding finishes compared with the as-welded one. The strain concentration effect in the connection is also greatly reduced in the specimens with post weld treatment compared with the as-welded one, which was also verified in the tests.

• Smart Structures and Systems
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• v.23 no.4
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• pp.337-345
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• 2019

This work resumes a research that proposes the use of the technique based on the dissipation energy of the shape memory alloy (SMA) ties. It focuses principally on the assessment of the effectiveness of the use of these smart materials on displacements, accelerations and the stresses of the minaret of the great mosque of Ajloun in Jordan. The 3-D finite element model of the minaret is performed by the ANSYS software. First of all, the proposed model is calibrated and validated according to the experimental results gathered from ambient vibration testing results. Then, a nonlinear transient analysis is considered, when the El-Centro earthquake is used as the input signal. Different simulating cases concerning the location, number and type of SMA devices are proposed in order to see their influence on the seismic response of the minaret. Hence, the results confirm the effectiveness of the proposed SMA device.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.51-117
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• 2019

On 15th November 2017, the coastal city of Pohang, located in the Southeastern part of South Korea was shaken by a magnitude 5.4 earthquake. The earthquake displaced more than 1,700 residents and caused more than $ 300 million dollars of economic loss. It was the second most damaging earthquake in the history of Korea. Soon after the earthquake, a group of scientists raised a possible link between the first Enhanced Geothermal System (EGS) project and the earthquake. At the same time, another group of scientists put forward a different hypothesis of the causation of the earthquake claiming that it was caused by the geological movements that were initiated by the Great Tohoku Earthquake in 2011. Since then, there were scientific debates between the two different groups of scientists. The scientific debate on the causation of the earthquake has been concluded temporarily by the Research Investigatory Committee on the Pohang Earthquake in 2019. The research committee concluded that the earthquake was caused by the Pohang EGS system: this means that the earthquake can be defined not as a natural earthquake, but as an artificially triggered earthquake. This article is to examine the Pohang earthquake can be defined as an Anthropocenic event. The newly suggested concept, the Anthropocene is a relatively novel term to classify the earthly strata and their relationship to geological time. The current geological period should be defined by human activities and man-made earthly environment. Although the term is basically related to geological classification, the Anthropocene has been widely debated amongst humanist and social science scholars. The current disastrous situation of our planet also implies with the Anthropocene. This paper is to discuss how to understand anthropogenic events. In particular, the paper pays attention to two different scholarly positions on the Anthropocene: Isabelle Stenger's Gaia theory and Barbara Herrnstein Smith's relativist theory. The former focuses on the earthly inevitable catastrophe of Anthropocene while the latter suggests to situate and contextualise anthropogenic events. On the basis of the theoretical positions, the article is to analyse how the Pohang earthquake can be located and situated.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.860-863
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• 2009

1923년 관동대지진으로 동경시내 교육시설 대부분이 파괴되었다. 이의 복구사업으로 동경시에서 건설했던 부흥소학교는 근대 일본 학교건축의 재료가 목조에서 철근 콘크리트조로 바뀌는 계기가 되었으며, 이와 함께 학교건축의 진일보한 면모를 보여주는 것이기도 하였다. 본고는 이러한 중요성을 가진 동경시 부흥소학교 건축의 특성을 주요 계획기준들을 중심으로 고찰하였다.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.700-705
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• 2005

This study presents a fatigue line with a plastic rotational angle to a great extent of plastic strain of Low-Cycle-fatigue period, such as earthquake, etc. This fatigue line with a plastic rotational angle is measured and analysed more simply in practice rather than Woehler's fatigue line which is developed in stress variation of the structure. It shows that the slope of fatigue line with a plastic rotational angle is equal to that with plastic strain through the experiments by proving the correlation that the plastic strain ratio is directly proportional to the plastic rotational angle in plastic hinge.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.25-28
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• 2001

The Seoul World-Cup Stadium is a representative stadium of Korea that 2002 Korea-Japan World-Cup will be held in. It is designed for structural safety, economical efficiency during the construction, easy maintenance, and the utilization after the festival. Also, it is considered that this stadium has sufficient safety against the earthquake, wind, and snow through 3-dimensional dynamic analysis. In addition, We hope that 2002 Korea-Japan World-Cup gets great success.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.4
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• pp.388-403
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• 2016

On July 5, 2016, offshore magnitude 5.0 earthquake, Ulsan, Republic of Korea can anxiety not safe in the earthquake. The gas smell that occurred in Busan on July 20, 2016 did not understand a cause and spread by the ghost story for the earthquake to a citizen. Thus correct information about the disaster is important to the smart city and the quick correspondence for damage inhabitants and the community has an influence on the disaster resilience. This study is targeted for damage inhabitants, and it clarifies the importance of the evocation model of anxiety about the disaster in the smart city with social technology. In the case of the Great East Japan Earthquake, consider the self-help contents of Kamaishi-city inhabitants deeply and find out a proper application method. As a means of disaster response and recovery, suggest that the inhabitants and community will be able to practice self-help measures.

• Geophysics and Geophysical Exploration
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• v.16 no.4
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• pp.234-239
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• 2013

The $M_W$ 9.0 thrust-fault earthquake has occurred in the Pacific coast of Tohoku, Japan, on March 11, 2011. We present the detection of the great earthquake and analyze T-waves associated with the main event and two other big aftershocks ($M_W$ > 7) recorded in a hydroacoustic array (H11N) in the Pacific Ocean by performing array and spectral analysis to examine characteristics of T-waves generated from the big events. The complex rupture process of the main event directly influences on the shape of the T-waves, and the peak locates on where T-waves excited from fast rupturing process arrive. We compare the two aftershocks with different fault type and show that the fault type and the source depth change shape and spectral contents of T-waves.

• Journal of Korean Society of societal Security
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• v.3 no.1
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• pp.67-73
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• 2010

School is a place to be done the education of Disaster Prevention and to be established the function of Disaster Prevention and seismic performance to secure the safety of children as well as emergency evacuation facilities for local communities in case of disaster. To improve the ability of Earthquake Disaster Prevention for students and teachers schools have to put the Earthquake Disaster Prevention on the subjects, for an example ethics, social study, science and gym and make a plan to efficiently manage school disaster prevention facilities. Seismic retrofitting on school facilities have to be established with the method of construction for steel bracings and seismic shear walls choosing old architectures first which is not the design with the seismic performance considering educational environmental aspects, and reconstruction of old architectures to get the agreement of societies. Furthermore, there is great demand for the effective, efficient and systematic improvement of school facilities for the use of shelters to be disaster prevention facilities.

• Journal of the Korea Convergence Society
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• v.10 no.6
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• pp.25-31
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• 2019

Because of its physical characteristics, earthquake has a great impact on a wide area in a short time, so it needs a resilience based seismic countermeasures to restore the community function. For this reason, in this study, the seismic damages of urban buildings were assessed stochastically by virtual earthquakes using public data information and disaster management program(Ergo-EQ). A geographical map reflecting geological characteristics of the target area was created with the buildings and topographic data in Dalseo-gu, Daegu City. In addition, an integrated database including building characteristics was modified to be linked with the Ergo-EQ program. The seismic damages for the buildings were evaluated through the exceedance probability of four different damage levels. From the damage results, it can be identified not only the seismic damage of each building, but also the major factors affecting earthquake damage.