• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.04a
• /
• pp.192-197
• /
• 2004

폐기물 매립층의 침하는 매립 폐기물의 조성특성의 영향으로 인하여 침하특성이 일반 흙의 토질역학적 거동과 다르게 나타난다. 폐기물의 침하특성은 매립당시 나타나는 폐기물 하중에 의한 침하특성과 향후 장기적으로 유발되는 생화학적 침하특성을 구분하여 규명하는 것이 필요하다. 본 연구에서는 국내 대표적 매립지 폐기물 침하에 대한 계측자료를 바탕으로 역학적 일차 압축침하와 생화학적 이차 압축침하에 대한 침하특성계수를 산정하였다. 또한 Sower(1973)의 매립지 폐기물에 대한 침하량 산정식을 응용하여 다단형 매립지 폐기물에 적용할 수 있는 침하량 산정식을 구성하였다.

• Geotechnical Engineering
• /
• v.13 no.2
• /
• pp.65-76
• /
• 1997

It has been a growing concern how to use Nanji-Island landfill and other refuse landfills located around metropolitan areas. In this paper, settlement characteristics of Nanji -Island landfill were studied by analyzing the data collected over the period of two years. The settlement characteristics were similar to the analyzed settlement characteristics of 24 refuse landfills in the United States. The model proposed by Bjarngard and Edger(1990) model is considered to be suitable for the long-term prediction of Wnil -Island landfill. The ten-year -period prediction value of Bjarngard and Edger (1990) model is considerably different from that of Power Creep Model. If existing settlement models used for long-term prediction of the settlement characteristics of landfill are not analyzed thoroughly there remains the possibility of including considerable prediction errors.

• Journal of the Korean GEO-environmental Society
• /
• v.17 no.8
• /
• pp.39-44
• /
• 2016

Ground deformation around construction site in urban area where typically adjacent structures are located needs to be strictly controlled. Accordingly, it is very important to precisely monitor the ground deformation. Settlement beacon is typically employed to measure the ground deformation, but meanwhile the rapid development in electronic technology enables 3D image scanner to become available for measuring the ground deformation profile in usual construction sites. With respect to the profile measurement, the 3D scanner has an advantage, whereas its accuracy is somewhat limited because it does not measure the displacement directly. In this paper, we developed a conditional merging technique to combine the ground displacement measured from settlement beacon and the profile measured by the 3D scanner. Synthetic ground deformation profile was generated to validate the proposed technique. It is found that the ground deformation measurement error can be reduced significantly via the conditional merging technique.

• Journal of the Korean GEO-environmental Society
• /
• v.6 no.1
• /
• pp.53-62
• /
• 2005

This paper estimates the long-term settlement of Kimpo metropolitan landfill based on measured settlement data from 180 landfill monitors accumulated over a period of 12 years. Comparison of domestic and international settlement records indicate that the domestic compression rate is slightly lower due to greater portion of organic component. Several existing settlement models are used to compare with the observed behavior and also to estimate long-term settlement. The hyperbolic, Gibson & Lo, Bjarngard & Edgers and Power Creep Law models compare well with the measured settlement of the Kimpo metropolitan landfill. The settlement models are further used to estimate long-term settlement. Bjarngard & Edgers and Power Creep Law models result in higher estimates of the long-term settlement compared to the hyperbolic and Gibson & Lo models. Further comparisons indicate that other models, including Sowers and log models, are inapproriate for predicting the long-term settlement of the Kimpo metropolitan landfill.

• Proceedings of the KSRS Conference
• /
• 2007.03a
• /
• pp.296-300
• /
• 2007

본 연구에서는 강원도 정선지역 및 삼척지역의 폐탄광 지역에서 관측된 지반침하지역의 공간자료와 각종 지반침하 관련요인을 분석하여, 지질학적구조와 지역적 특성이 상이한 지역에서 지반침하에 직접적인 영향을 주는 공통요인을 찾아내고자 하였다. 연구지역의 지반침하 관련요인들에 대해 GIS(Geographic Information System)를 이용하여 래스터 데이터베이스를 구축하고 모든 요인을 이용하여 분석한 위험지역과 하나의 요인씩 제거하며 분석한 위험지역을 비교하는 민감도 분석 (Sensitivity analysis)을 통해 지반침하와 연관성이 높은 요인을 추출하였다. 민감도 분석은 서로 다른 두 지역에 대해 수행하여 그 결과를 비교하였으며, 갱으로부터의 수평거리，RMR(Rock Mass Rating), 지하수 심도가 지반침하에 영향을 주는 공통요인으로 분석되었다. 본 연구결과, 폐탄광지역의 지반침하에 공통적으로 영향을 끼치는 주 요인을 구할 수 있었으며, 타 지역에서 지반침하 예측시 기존 연구에서 사용한 요인들의 데이터를 전부 구하지 못하는 경우에도 최소한의 필요한 요인을 정할 수 있으며 지반침하 예측의 효율성을 높일 수 있을 것이라 기대된다.

• Geotechnical Engineering
• /
• v.13 no.6
• /
• pp.5-12
• /
• 1997

Predictions of settlements under preloading for the improvement of soft soil is a very important element of construction management. Due to the non uniformity, difficulty of estimating resonable soil properties, predictions of settlements and settlement velocities at the design stage seldom agree with the actual future settlements. To overcome this problem, the prediction methods based on the settlement observation of initial preloading stage such as hyperbolic method and Asaoka method have been employed frequently. However the estimating method for the reliability of these predictions at the time of prediction has not been suggested. In this study, comparisons of predicted settlements by hyperbolic met hed and observed settlements are explored through case studies. And a stratagem of estimating reliability of settlement predictions by hyperbolic method is suggested as the result of investigation on the relationship between the initial observed time and error of settlement prediction by hyperbolic method.

• Journal of the Korean Geotechnical Society
• /
• v.16 no.2
• /
• pp.41-50
• /
• 2000

본 연구에서는 여러 침하모델들을 매립경과기간이 다른 아홉 개 지역의 실제 스레기 매립지 침하자료들에 적용하였다. 침하모델들을 적용한 결과, 매립연한이 증가할수록 향후 발생가능한 장기침하량도 상당히 감소하는 경향을 보였다. 신선한 쓰레기 매립지에서는 침하모델들마다 예측정도에서 큰 차이를 보이지만, 매립연한이 오래된 매립지들에서는 Power creep law를 제외하고는 예측정도에 있어서 큰 차이를 보이지 않음을 알 수 있었다.

• Tunnel and Underground Space
• /
• v.23 no.1
• /
• pp.31-41
• /
• 2013

Graphical method has been widely applied to the prediction of subsidence area, and is known to have advantages in analysis of trough subsidence which is common in horizontally seamed mine area. However, it is reported that most of the ore bodies in Korea are geologically inclined from sub-horizontal to steep, and therefore, the sinkhole subsidence is frequent in abandoned mine area. For these reasons, it is not to be desired that graphical method is applied for predicting the subsidence occurrence. This paper describes the results of subsidence zone prediction considering the dip direction and the opposite direction of inclined ore bodies from the case studies on the 163 subsidence occurrence regions. The results show also the assumed angle which can define the range of subsidence in the surface area. In conclusion, the limit of this angle is suggested after taking into account the comparison with graphical method and the application to the case histories.

• Journal of the Korean Geosynthetics Society
• /
• v.23 no.2
• /
• pp.9-17
• /
• 2024

When constructing on soft ground, managing ground settlement and safety is crucial. However, there often exists a significant disparity between the actual behavior of the ground and the design plans. In this study, we aimed to compare and analyze the difference between the predicted settlement based on theoretical formulas and the measured settlement during construction, in order to predict settlement. For this purpose, we analyzed settlement data from 18 construction sites. The results indicated that the back analysis settlement values were similar to the measured settlement values, whereas the design settlement values were significantly higher compared to the measured settlement values. Specifically, the design settlement values were 1.2 to 1.4 times higher than those derived from back analysis using measured values. The RMSE analysis revealed a value of 0.6212m for the design settlement and 0.1697m for the back analysis settlement. The difference between the back analysis settlement and the measured settlement was more than 70% lower than the difference between the design settlement and the measured settlement. This indicates that the back analysis settlement values exhibit lower error rates compared to the design settlement values.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.5
• /
• pp.399-409
• /
• 2018

The mechanically stabilized earth wall (MSEW) of the IPM bridge is an important structure that constitutes the bridge, and supports the horizontal earth pressure and approach slab. Therefore, it is necessary to carefully analyze the settlement of MSEW of the IPM bridge. This study examined the settlement according to the height and ground stiffness on the MSEW on the IPM Bridge. According to the design guideline, the IPM Bridge (2016) was designed to have a height of 4.0 ~ 10.0m and the elastic settlement was calculated. The base area and the grounding pressure of the MSE wall increased linearly with the height, and the elastic settlement also increased linearly. In addition, the stiffness of the foundations satisfying the allowable settlement of the approach slab is a N value of 35 or more. The settlement of finite element analysis was estimated to be smaller than the elastic settlement, and the stiffness of the foundation ground satisfied the allowable settlement of the approach slab above N value of 20. Because the elastic settlement of the MSEW of the IPM Bridge was overestimated, it will be necessary to examine it carefully by finite element analysis.