• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.17-35
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• 2016

Earthquake-induced disasters are often more severe in locations with soft soils than firm soils or rocks due to differences in ground motion amplification. On a regional scale, such differences can be estimated by spatially predicting subsurface soil thickness over the entire target area. In general, soil deposits are generally deeper in coastal or riverside areas than in inland regions. In this study, a coastal metropolitan area, Incheon, was selected to assess site effects and provide information on seismic hazards. Spatial prediction of geotechnical layers was performed for the entire study area within the GIS framework. Approximately 7,000 existing borehole drilling data in the Incheon area were gathered and archived into the GIS Database (DB). In addition, surface geotechnical data were acquired from a walkover survey. Based on the built geotechnical DB, spatial zoning maps of site-specific seismic response parameters were created and presented for use in a regional seismic strategy. Site response parameters were performed to determine site coefficients for seismic design over the entire target area and compared with each other. Site classifications and subsequent seismic zoning were assigned based on site coefficients. From this seismic zonation case study in Incheon, we verified that geotechnical GIS-DB can create spatial zoning maps of site-specific seismic response parameters that are useful for seismic hazard mitigation particularly in coastal metropolitan areas.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.203-218
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• 2010

The site categorization and corresponding site amplification factors in the current Korean seismic design guideline are based on provisions for the western United States (US), although the site effects resulting in the amplification of earthquake ground motions are directly dependent on the regional and local site characteristic conditions. In these seismic codes, two amplification factors called site coefficients, $F_a$ and $F_v$, for the short-period band and midperiod band, respectively, are listed according to a criterion, mean shear wave velocity ($V_S$) to a depth of 30 m, into five classes composed of A to E. To suggest a site classification system reflecting Korean site conditions, in this study, systematic site characterization was carried out at four regional areas, Gyeongju, Hongsung, Haemi and Sacheon, to obtain the $V_S$ profiles from surface to bedrock in field and the non-linear soil properties in laboratory. The soil deposits in Korea, which were shallower and stiffer than those in the western US, were examined, and thus the site period in Korea was distributed in the low and narrow band comparing with those in western US. Based on the geotechnical characteristic properties obtained in the field and laboratory, various site-specific seismic response analyses were conducted for total 75 sites by adopting both equivalent-linear and non-linear methods. The analysis results showed that the site coefficients specified in the current Korean provision underestimate the ground motion in the short-period range and overestimate in the mid-period range. These differences can be explained by the differences in the local site characteristics including the depth to bedrock between Korea and western US. Based on the analysis results in this study and the prior research results for the Korean peninsula, new site classification system was developed by introducing the site period as representative criterion and the mean $V_S$ to a depth of shallower than 30 m as additional criterion, to reliably determine the ground motions and the corresponding design spectra taking into account the regional site characteristics in Korea.

• Journal of Soil and Groundwater Environment
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• v.25 no.3
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• pp.32-42
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• 2020

오염부지 관리 기조가 매체 중심에서 수용체 중심으로 변화하면서 우리나라에 위해성평가 제도가 도입되었으나, 이를 오염현장에 충분히 활용하기 위한 체계와 관련 기술들은 아직 제대로 확립되어 있지 않다. 특히, 여러 가지 이유로 정화곤란부지로 분류가 되는 오염부지의 정화 및 관리와 그러한 부지에 적용될 수 있는 위해저감기술들에 대한 기술적, 사회적 논의와 합의도 부족한 실정이다. 본 연구에서는 그동안 오염토양의 정화에만 초점이 맞추어진 우리나라의 토양환경정책이 오염부지의 관점에서 그와 연결된 수용체를 보호하는 방향으로 나아가기 위해 필요한 위해성기반 오염 부지관리 의사결정체계를 제안하고, 그러한 관리체계가 현장에서 적절히 적용되도록 하기 위해 필요한 위해저감기술들을 조사, 분류하여 위해저감 방식에 따른 위해저감기술의 활용성 및 적용성을 평가하는 방안을 제안하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.17-17
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• 2023

국내의 부지특성 및 감시 관련 규정은 원자력 안전위원회 고시 제2021-16호 제4조(세부지침)와 원자력 안전위원회 고시 제2021-17호 제16조에 의거하고, 국외는 국제원자력기구(IAEA: International Atomic Energy Agency)에서 안전기준을 제시하고 있다(IAEA, 2011). 따라서 국내 중·저준위 방사성폐기물 처분시설은 2006년부터 광역 지질을 포함한 부지 지질/지형, 기상, 수문, 수리지질, 인문사회 등을 망라한 조사를 시행하여 부지 현황에 대한 분석 및 안정성 평가를 수행한다. 부지감시의 수문·지구화학 분야에서는 현장 수질 측정 6항목과 실내 분석 26항목을 감시하고 있으나, 본 연구는 이 중 9개 항목(EC, Na, K, Ca, Mg, SiO₂, Cl, SO₄, HCO₃)을 선정하여 분석하였다. 연구 목적은 물시료 분석자료의 주성분-다중선형회귀-군집 분석과 Piper Diagram 분석결과로부터 해수와 담수(지하수)와의 특성분석 및 해수 영향을 분석하는 것이다. 현장 부지내 지하수 7개 관정(GM-1, 2, 4, 5, 6, 7, 8)과 해수 2개 지점(Sea-1, 2)을 대상으로 통계학적 주성분 분석결과, 대부분의 지하수는2개~4개의 요인으로 구분되고, 해수와의 유사성을 해석하기 위해 확인한 관정은 GM-5, GM-6, GM-1 지점으로 분류되었다. 상기와 같이 해수의 영향을 확인하기 위해 해수 2개 지점과 동일한 군집으로 분류되는 지하수는 GM-5 관정으로 확인되었고, 해안선에서 가까운 GM-5 관정과 같이 유사한 거리에 분포한 지하수 GM-1, 2, 4 관정은 2개 혹은 3개의 최적 군집으로 분류하였을 때도 GM-5와는 다른 특성을 보여주었다. 이는 해안과 인접하더라도 수질은 다른 지질학적 특성(지형, 기상, 단열대 등)에 따라 영향받았음을 지시한다.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.32-49
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• 2010

Site characterization on geological and geotechnical conditions was performed for evaluating the earthquake ground motions associated with seismic site effects at a small urbanized area, Hongseong, where structural damages were recorded by an earthquake of magnitude 5.0 on October 7, 1978. In the field, various geotechnical site investigations composed of borehole drillings and seismic tests for obtaining shear wave velocity profile were carried out at 16 sites. Based on the geotechnical data from site investigation and additional collection in and near Hongseong, an expert system on geotechnical information was implemented with the spatial framework of GIS. For practical application of the GIS-based geotechnical information system to assess the earthquake motions in a small urban area, spatial seismic zoning maps on geotechnical parameters, such as the bedrock depth and the site period ($T_G$), were created over the entire administrative district of Hongseong town, and the spatial distributions of seismic vulnerability potentials were intuitively examined. Spatial zonation was also performed to determine site coefficients for seismic design by adopting a site classification system based on $T_G$. A case study of seismic zonation in the Hongseong area verified that the GIS-based site investigation was very useful for regional prediction of earthquake ground motions in a small urbanized inland area.

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.1-13
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• 2007

In order to evaluate the local site effects at two town fortress areas in Korea where stone parapets were col-lapsed by historical earthquakes, site characteristics were assessed using site investigations such as borehole drillings and seismic tests. Equivalent-linear site response analyses were conducted based on the shear ways velocity ($V_s$) profiles and geotechnical characteristics determined from site investigations. The study sites are categorized as site classes C and B according to the mean $V_s$ to 30 m ranging from 500 to 850 m/s, and their site periods are distributed in the short period range of 0.06 to 0.16 sec, which contains the natural period of fortress wall and stone parapet. From the results of site response analyses in the study areas, for site class C indicating most of site conditions, contrary to site class B, the short-period (0.1-0.5 sec) and mid-period (0.4-2.0 sec) site coefficients, $F_a$ and $F_v$ specified in the Korean seismic design guide, underestimate the ground motion in short-period band and overestimate the ground motion in mid-period band, respectively, due to the high amplification in short period range, which represent the site-specific seismic response characteristics. These site-specific response characteristics indicate the potential of resonance in fortress walls during earthquake and furthermore could strongly affect the collapse of parapets resulted from seismic events in historical records.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.10-27
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• 2014

HAZUS-MH is a GIS-based computer program that estimates potential losses from multi-hazard phenomena: earthquakes, floods and hurricanes. With respect to seismic disaster, characteristics of a hypothetical or actual earthquake are entered into HAZUS. Then HAZUS estimates the intensity of ground shaking and calculates the correspondent losses. In this study, HAZUS was used as a part of the preparations of the future seismic events at a coastal plant facility area. To reliably characterize the target facility area, many geotechnical characteristics data were synthesized from the existing site investigation reports. And the buildings and facilities were sorted by analyzing their material and structural characteristics. In particular, the study area was divided into 17 blocks taking into account the situation of both land development and facility distribution. The ground conditions of blocks were categorized according to the site classification scheme for earthquake-resistant design. Moreover, seismic fragility curves of a main facilities were derived based on the numerical modeling and were incorporated into the database in HAZUS. The results estimated in the study area using HAZUS showed various seismic damage and loss potentials depending on site conditions and structural categories. This case study verified the usefulness of the HAZUS for estimating earthquake losses in coastal facility areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3997-4001
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• 2014

The aim of this study was to suggest site-specific reuse alternatives for closed unsanitary landfills (CULs) scattered in Gyeongbuk Province. The CULs were classified with the factors affecting the site reuse alternative to provide basic data for systematic site reuse. Statistical analysis showed that the site area was the main factor in site classification among the site area, distance to road, and distance to the village. The results proposed a site-specific guide flow to the reuse of the CULs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1C
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• pp.65-76
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• 2010

Recent earthquake events revealed that severe seismic damages were concentrated mostly at sites composed of soil sediments rather than firm rock. This indicates that the site effects inducing the amplification of earthquake ground motion are associated mainly with the spatial distribution and dynamic properties of the soils overlying bedrock. In this study, an integrated GIS-based information system for geotechnical data was constructed to establish a regional counterplan against ground motions at a representative metropolitan area, Seoul, in Korea. To implement the GIS-based geotechnical information system for the Seoul area, existing geotechnical investigation data were collected in and around the study area and additionally a walkover site survey was carried out to acquire surface geo-knowledge data. For practical application of the geotechnical information system used to estimate the site effects at the area of interest, seismic zoning maps of geotechnical earthquake engineering parameters, such as the depth to bedrock and the site period, were created and presented as regional synthetic strategy for earthquake-induced hazards prediction. In addition, seismic zonation of site classification was also performed to determine the site amplification coefficients for seismic design at any site and administrative sub-unit in the Seoul area. Based on the case study on seismic zonations for Seoul, it was verified that the GIS-based geotechnical information system was very useful for the regional prediction of seismic hazards and also the decision support for seismic hazard mitigation particularly at the metropolitan area.

• Ecology and Resilient Infrastructure
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• v.4 no.2
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• pp.83-92
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• 2017

Increased investment in environment-friendly transport vehicles has led to rapid transit of railway tracks, double track program, linear improvements in railway lines, and moving railroad routes into the suburbs. They resulted in fast increase of railway yards. However, as the railroad yards being neglected, urban fine sites have been degraded. Local governments kept seeking ways to utilize the railway yards. In addition, Ministry of land, infrastructure and transport enacted "Guidelines for utilization of railway yards". The Guidelines categorized the railway yards into three types; conservation, utilized, and other sites in order to make efficient use of them. The railway yards have been converted and used for parks, rail bike trails, bike paths, and solar projects. It seems that studies are needed on diverse use of the yards and on post evaluation. This study investigated current uses of railway yards, domestic and foreign, and analyzed for the pertinent conditions on natural and cultural landscape, educational value, location and accessibility, potential for recreational area, and development opportunities. In this study, I proposed a quantitative evaluation method, and to find way to diversify the use of railway yards.