• International Journal of Advanced Culture Technology
• /
• 제6권4호
• /
• pp.255-261
• /
• 2018

In the field of excavation, it is important to recognize and analyze the factors that cause the ground collapse in order to predict and cope with the ground subsidence. However, it is difficult for field engineers to predict ground collapse due to insufficient knowledge of ground subsidence influence factors. Although there are many cases and studies related to the ground subsidence, there is no manual to help practitioners. In this study, we present the criteria for describing and quantifying the influential factors to help the practitioners understand the existing ground collapse cases and classification of the ground subsidence factors revealed through the research. This study aims to improve the understanding of the factors affecting the ground collapse and to provide a GSRp for the ground subsidence risk assessment which can be applied quickly in the field.

• 한국방재안전학회논문집
• /
• 제10권1호
• /
• pp.29-34
• /
• 2017

This Analyzed case study of measuring displacement, implemented laboratory investigation, and in-situ testing in order to interpret ground subsidence risk rating by excavation work. Since geological features of each country are different, it is necessary to objectify or classify quantitatively ground subsidence risk evaluation in accordance with Korean ground character. Induced main factor that could be evaluated and used to predicted ground subsidence risk through literature investigation and analysis study on research trend related to the ground subsidence. Major factors of ground subsidence might be classified by geological features as overburden, boundary surface of ground, soil, rock and water. These factors affect each other differently in accordance with type of ground that's classified soil, rock, or complex. Then rock could be classified including limestone element or not, also in case of the latter it might be classified whether brittle shear zone or not.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
• /
• pp.325-328
• /
• 2005

To estimate presumptive local ground subsidence area near Abandoned Under ground Coal Mine(AUCM) at Samcheok city in Korea, the geological properties of existing ground subsidence area and the geophysical prospecting data were analyzed using GIS. The electrical resistivity survey and seismic reflection survey database were constructed from investigation reports and factors which are related with ground subsidence such as geological map, topological map, land use map, lineament map, groundwater level, RMR (Rock Mass Rating), mining tunnel map and slope database were constructed also to make a comparative study of each parameters. As a result of the spatial analysis of existing ground subsidence area, 9 major factors causing ground subsidence were extracted and a connection between the structure of underground and the ground subsidence was determined from the analysis of geophysical prospecting data. The estimation of presumptive ground subsidence area was performed using the correlation between the result from neural network analysis of 9 factors and the scrutiny of geophysical prospecting data.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
• /
• pp.717-720
• /
• 2006

In this study, we predicted locations vulnerable to ground subsidence hazard using fuzzy logic and geographic information system (GIS). Test was carried out at an abandoned underground coal mine in Samcheok City, Korea. Estimation of relative ratings of eight major factors influencing subsidence and determination of effective fuzzy operators are presented. Eight major factors causing ground subsidence were extracted and constructed as a spatial database using the spatial analysis and the probability analysis functions. The eight factors include geology, slope, landuse, depth of mined tunnel, distance from mined tunnel, RMR, permeability, and depth of ground water. A frequency ratio model was applied to calculate relative rating of each factor, and the ratings were integrated using fuzzy membership function and five different fuzzy operators to produce a ground subsidence susceptibility map. The ground subsidence susceptibility map was verified by comparing it with the existing ground subsidences. The obtained susceptibility map well agreed with the actual ground subsidence areas. Especially, ${\gamma}-operator$ and algebraic product operator were the most effective among the tested fuzzy operators.

• 한국농공학회논문집
• /
• 제59권5호
• /
• pp.83-91
• /
• 2017

Recently, ground subsidence frequently occurs in downtown area. The major causes of the subsidence on the subsurface were the damages of the water supply and sewer pipelines and excavation works in adjacent areas, etc. Because of these various factors, it is not easy to analyze the tendency of occurrence of ground subsidence. The purpose of this study is to clarify the effect of ground subsidence by the change of the fine particle content and ground water level and to establish the ground subsidence mechanism. In this study, a model soil-box was manufactured to simulate the failure of the old sewer pipe which is one of the causes on ground subsidence. And a model test was conducted to investigate the effects of fine contents and ground water level on the cavity occurrence. From the test results, firstly the higher the ground water level, the faster the primary cavity is formed as the seepage stress increases. As a result, the secondary cavity and the ground subsidence rapidly progress due to the relaxation of the surrounding ground. The total amount of discharged soil was decreased as the fine content increased.

• 한국지반환경공학회 논문집
• /
• 제23권8호
• /
• pp.5-10
• /
• 2022

인구 밀집도가 높은 도시 중심지에서 발생하는 지반함몰의 주요 원인은 하수관 및 상수관과 같은 지하매설물의 손상으로 알려져 있다. 이와 관련하여 지반함몰의 원인 규명과 지반함몰 위험 예측에 관한 연구가 꾸준히 수행되고 있다. 현재 지반함몰은 지중탐사레이더를 통해 선제적으로 공동을 발견하여 대응하고 있으나, 이는 인력 및 비용의 소비가 크기 때문에 효율적인 장비의 운영을 위해 위험지역을 예측하고 예측된 지역을 우선순위로 탐사해야 할 필요가 있다. 따라서 본 연구에서는 ◯◯시의 2개 구를 500m×500m 크기의 그리드로 분할하고, 해당 그리드 내의 지하매설관 속성과 지반함몰 발생 데이터를 활용하여 데이터셋을 구축하였다. 구축된 데이터셋으로 기계학습을 통한 적절한 지반함몰 위험등급 예측 모델을 제시하였고, 제시된 모델을 활용하여 대상지역의 지반함몰 위험지도를 제시하고자 하였다.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
• /
• pp.728-731
• /
• 2006

Ground subsidence near abandoned underground coal mines has become a serious social problem in Korea. The purpose of this study is to perform a comparative analysis between the ground subsidence area and the electrical resistivity measured by field survey at Samcheok City. A raster database composed of ground subsidence areas and electrical resistivity data was constructed for GIS. To analyze correlation between the two constructed raster datasets, we used a frequency ratio model. The results show that low and high electrical resistivity anomaly zones coincide with the existing subsidence areas. We infer that the high anomaly zone means saturated and low anomaly zone means vacant. It suggests that electrical resistivity might be a useful factor for analyzing ground subsidence hazard zone.

• 지질공학
• /
• 제29권3호
• /
• pp.289-302
• /
• 2019

최근 굴착현장 인근의 지반함몰 발생사례가 증가함에 따라 사전에 지반함몰 가능성을 예측할 수 있는 연구가 진행되고 있다. 본 연구에서는 기존 연구에 의해 개발된 굴착 전 지반함몰 위험등급 평가 시트인 GSRp를 실제 굴착 현장에 적용하여 현장 적용성을 검증하였다. 각각 다른 지반조건을 가진 5개 굴착현장에 대하여 지반함몰 위험등급을 평가한 결과, GSRp 점수는 40~79점으로 산출되어 대부분 II등급(우수지반)~III등급(양호지반)으로 분류되었다. 평가방법의 신뢰성 검증을 위하여 계측결과에 의해 실측된 수평변위량과 비교 분석하였다. 본 연구현장의 수평변위량은 허용치의 25~47%로 나타나 지반함몰 위험이 낮게 평가된 GSRp 결과와 일치하였다. 향후 지반함몰 위험성이 높은 불량한 지반을 대상으로 하는 현장 적용에 대한 연구가 진행되어 검증과 보완이 이루어진다면 GSRp 평가방법이 굴착 전 지반함몰 위험도를 예측하는 평가 도구로 활용될 수 있을 것으로 기대된다.

• 한국안전학회지
• /
• 제32권6호
• /
• pp.104-109
• /
• 2017

As the ground subsidence occurred at the center of Seoul area in 2014, the ground subsidence phenomenon was emerged as a social issue in Korea. Even so far, national and local governments and related experts have been making a lot of efforts to prevent ground subsidence phenomenon, but it is still happening all over the country. In this study, we chose 9 influence factors on which ground subsidence and derived weights using AHP(Analytic Hierarchy Process) method for ground subsidence risk analysis. And we analyze the risk of subsidence in ${\bigcirc}{\bigcirc}$city using GIS(Geographic Information System) analysis method and evaluate the potential risk.

• 지질공학
• /
• 제31권2호
• /
• pp.135-148
• /
• 2021

굴착 전 지반조사 결과를 활용한 지반함몰 위험등급 분류는 시공 과정에서 들어나는 인자들에 따라 평가 결과가 다르게 나타날 수 있다. 본 연구에서는 기존 연구에서 제안된 굴착 전 지반조사 결과를 활용한 지반함몰 위험등급 분류 방법을 현장상황을 고려하여 보정하는 방법을 제시하였다. 굴착 진행 중 지하수위는 차수공법의 적용 여부나 시공 상태에 따라 유출되는 정도가 시공 전 예측결과와 다르게 나타난다. 굴착 중 급격한 지하수위 하강은 압밀이나 압축 등의 체적 감소로 지반함몰을 유발하고 집중 호우 등에 의한 수위 상승은 굴착 저면의 히빙이나 보일링을 발생시켜 지반함몰 위험도를 높인다. 굴착 중 흙막이 벽체의 과도한 변위나 지반침하는 지반함몰의 원인이 될 수 있으며, 매설된 관로의 파손을 야기하여 지반함몰 위험도를 높인다. 본 연구에서는 굴착 중 지하수 변동 및 유출상태, 지반변위, 흙의 종류 등을 고려하여 지반함몰 영향인자를 재평가하는 방법을 제안하였다. 최종적으로 지반함몰 평가의 영향인자를 5개 카테고리의 12개 영향인자로 평가할 수 있도록 개선하였다.