• Structural Engineering and Mechanics
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• 제27권1호
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• pp.77-97
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• 2007

When assessing buildings that may collapse during a large earthquake, conventional rapid visual screening procedures generally provide good results when identifying buildings for further investigation. Unfortunately, their accuracy at identify buildings at risk is not so good. In addition, there appears to be little room for improvement. This paper investigates an alternative screening procedure based on fuzzy logic and artificial neural networks. Two databases of buildings damaged during the Athens earthquake of 1999 are used for training purposes. Extremely good results are obtained from one database and not so good results are obtained from the second database. This finding illustrates the importance of specifically collecting data tailored to the requirements of the fuzzy logic based rapid visual screening procedure. In general, results demonstrate that the trained fuzzy logic based rapid visual screening procedure represents a marked improvement when identifying buildings at risk. In particular, when smaller percentages of the buildings with high damage scores are extracted for further investigation, the proposed fuzzy screening procedure becomes more efficient. This paper shows that the proposed procedure has a significant optimisation potential, is worth pursuing and, to this end, a strategy that outlines the future development of the fuzzy logic based rapid visual screening procedure is proposed.

• 한국공간구조학회논문집
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• 제11권4호
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• pp.89-99
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• 2011

최근 테러의 대상 범위는 보다 광범위해 지고 있으며, 국내의 테러발생위험이 지속적으로 증가하고 있는 가운데 테러의 형태는 국가의 중요시설과 같은 경성표적(Hard Target)에서 초고층건물과 같은 다중이용시설의 연성표적(Soft Target)으로 변화하고 있다. 따라서 본 논문에서는 Fema 455 - Rapid Visual Screening을 통해 국내의 초고층건물과 고층건물의 테러위험도 평가결과를 국내의 저층건물의 테러위험도 평가결과와 비교하여 초고층건물의 테러위험도를 분석하였다. 그 결과 초고층건물 및 고층건물은 저층건물에 비해 Consequences, Vulnerability Rating보다 Threat Rating항목이 상대적으로 높았으며, 이는 초고층건물의 거주인원 및 국가적 또는 지역적인 상징성 및 가시성 부분에서 테러위험도가 높은 것이 주요 원인으로 분석되었다.

• 한국공간구조학회논문집
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• 제12권4호
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• pp.91-98
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• 2012

As the occurrence rate of terror and hazard is increasing throughout the world, GSA, DoD, and FEMA are proceeding a study about mitigating the damage of terror. Korea is no more a safe place from the terrorist's threat, so we need to make measures against them. In this study we developed modified RVS System by revising some items to adjust the system to the domestic condition and conducted a risk assessment on several tall buildings in Korea. By using IRVS system which is developed by DHS, we also carried out the risk assessment. Comparing the results between RVS with IRVS, we performed terror risk evaluation of tall buildings. Through risk assessment of several tall buildings, we analyzed key factors of each scenarios and suggested the mean value of each items, so we would like to help the counter-terrorism in the design phase.

• 한국공간구조학회논문집
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• 제11권2호
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• pp.55-62
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• 2011

최근 테러의 발생빈도가 증가하는 가운데 테러는 불특정 다수의 사람이 모이는 건물에서 집중적으로 발생하고 있다. 이중 고층, 초고층 빌딩에서 발생하는 테러는 막대한 피해를 발생시킨다. 이에 따른 건물의 테러피해 경감을 위한 다양한 연구가 필요하다. 본 논문에서는 비교적 수행절차가 간단하며 단기간에 실행이 가능한 Fema 455 - Rapid Visual Screening을 통해 현재 사용 중인 국내 고층 초고층 건물의 테러에 대한 위험도를 평가하여 국내 건물이 가지는 공통적인 테러 위험요소를 확인하였다. 평가결과 대상 건물은 모두 중위험도의 범위에 있다. 이는 국내 고층, 초고층 건물의 외부 환경적인 특징이 비슷한 데에 그 원인이 있었다.

• Earthquakes and Structures
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• 제14권6호
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• pp.615-626
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• 2018

The seismic vulnerability of Turkey is relatively high due to its active fault systems with potential to create destructive earthquakes. Thus, reducing the loss of life and property, the number of the earthquake-prone buildings and their retrofit requirements are considerably significant key issues under the scenario earthquakes. The street survey based rapid assessment (SSRA) method can be considered as a powerful tool to determine the seismic vulnerability of building stock of an earthquake-prone city/state. In this study, the seismic vulnerability of the building stock of the Kirikkale province in Turkey is aimed to be estimated adopting the street survey based rapid assessment method (SSRA). For this purpose, central 2074 existing reinforced concrete (R/C) buildings were structurally surveyed with rapid visual site screening and disadvantages such as, the existence of short-column, soft-story, heavy overhangs, pounding effect and local soil conditions were determined for obtaining the structural performance score of each. The results obtained from the study demonstrate that 11-25% of the surveyed buildings in the study region needs to be investigated through more advanced assessment methods. Besides, higher correlation between increasing story number and unsafe/safe building ratio is obtained for the buildings with soft-story parameter than that for those with heavy overhangs and short-column parameters. The conformity of the results of the current study with the previous documented cases of rapid assessment efforts in the recent earthquakes in Turkey shows that the SSRA method for the Kirikkale province performed well, and thus this methodology can be reliably used for similar settlement areas.

• Computers and Concrete
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• 제31권3호
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• pp.185-195
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• 2023

Antalya is located south part of minor Asia, one of the biggest cities in Türkiye. As a result of population growth and vast migration to Antalya, many parts of the city that were not suitable for construction due to its geological conditions have become urban areas, and most of these urban areas are full of poorly engineered buildings. Poor engineering has been combined with unplanned urbanization, that causes utter vulnerability to disasters in Antalya. When an earthquake-prone city, Antalya faces with an earthquake risk, fear arises in society. To overcome this problem, it has become necessary to investigate the building stock, expressed in hundreds of thousands, in a fast and reliable way and then perform an urban transformation to create the perception of structural safety. However, the excessive building stock, labor, and economic problems made the implementation stage challenging and revealed the necessity of finding alternative solutions in the field. The present study presents a novel approach for assessment and model based on a rapid visual inspection method to transform areas under earthquake risk in Türkiye. The approach aimed to rank the interventions for decision-making mechanisms by making comparisons in the scale hierarchy. In the present study, to investigate the proposed approach, over 26,000 buildings were examined in Antalya, which is the fifth largest city in Türkiye that has a population of over 2.5 Million. In the results of the study, the risk classification was defined in the framework of building, block, street, neighborhood, and district scales.

• 농촌계획
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• 제13권3호
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• pp.23-32
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• 2007

In Korea, a regulation of visual impact evaluation on development plan in natural environment is provided at the Natural Environment Conservation Act, but it was difficult to obtained the effectiveness enough to conserve natural landscape. So, the visual impact review on development plan is introduced to the act, through the revision of the Natural Environment Conservation Act in 2005. The basic directions of visual impact review are preservation, restoration, view protection, and harmony. The items of review are as follows; (1) development alternations for the provided plan, (2) executive reduction plan of visual impacts including consideration of growth of plants, (3) deliberation process between persons or parties concerned, etc. For rapid settlement of visual impact review system, it needs that the validity, the reliability, and the objectivity should be confirmed through steady research about reasonable guidance of review.

• Structural Engineering and Mechanics
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• 제92권2호
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• pp.197-206
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• 2024

In this study, a unified framework that integrates pre- and post-earthquake assessments of buildings was proposed to enhance urban disaster preparedness through the coordination of pre- and post- earthquake efforts. Within this framework, a case study based on the 2023 Kahramanmaraş Earthquake was performed comparing the distribution of seismic risk prioritization for 117 reinforced concrete buildings with their actual damage states observed during post-earthquake field inspections. In order to conduct pre-earthquake evaluation process, street-level images were employed using two different rapid visual screening methods. With the use of generated geospatial database enabling the efficient and reliable transmission of the data between both stages of the assessment procedures, the alignment and validation of pre- and post-earthquake evaluations of the buildings were achieved enhancing the coordination of seismic risk management strategies. By implementing the proposed joint framework in this study, an extensive seismic vulnerability evaluation on an urban scale could be achieved by optimizing the computational demands, cost and time required for the strategic planning activities.

• Computers and Concrete
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• 제26권3호
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• pp.203-211
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• 2020

Turkey is located in one of the most seismically active regions of in Europe. The majority of the population living in big cities are at high seismic risk due to insufficient structural resistance of the existing buildings. Such a seismic risk brings the need for a comprehensive seismic evaluation based on the risk analysis in Turkey. Determining the seismic resistance level of existing building stock against the earthquakes is the first step to reduce the damages in a possible earthquake. Recently in January 2020, the Elazig earthquake brought the importance of the issue again in the public. However, the excessive amount of building stock, labor, and resource problems made the implementation phase almost impossible and revealed the necessity to carry out alternative studies on this issue. This study aims for a detailed investigation of residential buildings in Antalya, Turkey. The approach proposed here can be considered an improved state of building survey methods previously identified in Turkey's Design Code. Antalya, Turkey's fifth most populous city, with a population over 2.5 Million, was investigated as divided into sub-regions to understand the vulnerability, and a threshold value found for the study area. In this study, 26,610 reinforced concrete buildings between 1 to 7 stories in Antalya were examined by using the rapid visual assessment method. A specific threshold value for the city of Antalya was determined with the second level examination and statistical methods carried out in the determined sub-region. With the micro zonation process, regions below the threshold value are defined as the priority areas that need to be examined in detail. The developed methodology can be easily calibrated for application in other cities and can be used to determine new threshold values for those cities.

• International Journal of CAD/CAM
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• 제6권1호
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• pp.9-17
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• 2006

Performing inspections for Hull Condition Monitoring and Assessment as stipulated in IACS unified requirements and IMO's Condition Assessment Scheme (CAS) IMO Resolution MEPC.94(46), 2001, Condition Assessment Scheme, IMO Resolution MEPC.111(50), 2003, Amendments to regulation 13G, addition of new regulation 13H involves a huge amount of measurement data to be collected, processed, analysed and maintained. Information to be recorded consists of thickness measurements and visual assessment of coating and cracks. The amount of data and increasing requirements with respect to condition assessment demand efficient computer support. Currently, due to the lack of standardization for this kind of data, the thickness measurements are recorded manually on ship drawings or tables. In this form, handling of the measurements is tedious and error-prone and assessment is difficult. Data reporting and analysis takes a long time, leading to some repairs being performed only at the next docking of the ship or making an additional docking necessary. The recently started ED funded project CAS addresses this topic and develops-as a first step-a data model for Hull Condition Monitoring and Assessment (HCMA) based on XML-technology. The model includes simple geometry representation to facilitate a graphically supported data collection as well as an easy visualisation of the measurement results. In order to ensure compatibility with the current way of working, the content of the data model is strictly confined to the requirements of the measurement process. Appropriate data interfaces to classification software will enable rapid assessment by the classification societies, thus improving the process in terms of time and cost savings. In particular, decision-making can be done while the ship is still in the dock for maintenance.