• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.6
• /
• pp.1235-1240
• /
• 2019

It is well known that the ground water level changes rapidly before and after the earthquake, and the variation of ground water level prediction is used to predict the earthquake. In this paper, we predict the ground water level in Miryang City using ANFIS algorithm for earthquake prediction. For this purpose, this paper used precipitation and temperature acquired from National Weather Service and data of underground water level from Rural Groundwater Observation Network of Korea Rural Community Corporation which is installed in Miryang city, Gyeongsangnam-do. We measure the prediction accuracy using RMSE and MAPE calculation methods. As a result of the prediction, the periodic pattern was predicted by natural factors, but the change value of ground water level was changed by other variables such as artificial factors that was not detected. To solve this problem, it is necessary to digitize the ground water level by numerically quantifying artificial variables, and to measure the precipitation and pressure according to the exact location of the observation ball measuring the ground water level.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.457-467
• /
• 2010

The settlement prediction is very important to preloading method for a construction site on a soft ground. At the design stage, however, it is hard to predict the settlement exactly due to limitations of the site survey. Most of the settlement prediction is performed by a regression settlement curve based on the field data during a construction. In Korea, hyperbolic method has been most commonly used to align the settlement curve with the field data, because of its simplicity and many application cases. The results from hyperbolic method, however, may be differed by data selections or data fitting methods. In this study, the analyses using hyperbolic method were performed about the field data of $\bigcirc\bigcirc$ site in Pusan. Two data fitting methods, using an axis transformation or an alternative method, were applied with the various data group. If data was used only after the ground water level being stabilized, fitting results using both methods were in good agreement with the measured data. Without the information about the ground water level, the alternative method gives better results with the field data than the method using an axis transformation.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.18 no.1
• /
• pp.95-107
• /
• 2016

Ground water is one of important parameters in the designs of underpass structures because urban areas are characterized by soil ground which is relatively permeable than rock ground and a high level of ground water due to low elevation. Therefore, it is important properly to predict variations of the ground water when they can affect underpass structures. In this study, a series of numerical analyses are performed to predict the variations of ground water levels considering the degree of surface imperviousness and LID(Low Impact Development) application. In turn the stability of underground structure is assessed using predicted ground water level. The results show that an increase in the impervious surface area decreases the ground water level. The application of permeable pavement as a LID facility increases the ground water level, improving the infiltration capacity of rainfall into the ground. Seasonal variations of the ground water level are also verified in numerical simulation. The results of this study suggest that reasonable designs of underpass structures can be obtained with the suitable prediction and application of the ground water level considering the surface characteristics.

• Journal of the Korean Geotechnical Society
• /
• v.15 no.5
• /
• pp.111-124
• /
• 1999

When deep excavation adjacent to an existing structure is performed, it is very important to minimize damage on the structure through the prediction of ground movement. In this paper, finite element analysis was performed to predict the ground movement, based on the data from site investigation and laboratory tests, when deep excavation close to a buried water tank was carried out in soft clay ground. The movement and stabilities of the soil-cement wall(SCW) and the adjacent structure were checked using the results of the analysis and the field measurement. The comparison between the measured and the predicted ground movements showed the significance of the excavation procedure and lowering of water level in the analytical model. In the future, it is needed to improve the prediction method for better estimation of the ground movement.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2001.09a
• /
• pp.168-171
• /
• 2001

It is a common practice to extract water from the ground for domestic, agricultural or industrial uses or to lower the groundwater level for construction work. An accurate prediction of ground settlement Is sometimes crucial when groundwater is pumped. This case study have shown that drawdown of the groundwater table may cause ground subsidence. Many settlement gauges was installed in the vicinity of a pumped well to measure the surface settlement. The relationships between the level of groundwater drop and surface settlement is investigated In this research.

• Journal of the Korean Geosynthetics Society
• /
• v.10 no.4
• /
• pp.71-79
• /
• 2011

In this study, the variation of wetting front and ground water level at the embankment constructed in the Saemangeum area were predicted considering rainfall duration times and the slope stability analysis of the embankment was carried out according to prediction results of wetting front and ground water level. The embankment was formed by dredging soils. A suction stress, a cohesion and a frictional angle of dreding soils measured by soil tests were applied to estimate the unsaturated soil properties. According to the analysis results of the wetting front and the ground water level for various rainfall duration time, the wetting front began to descend from the upper part of embankment at the beginning time of rainfall and after 1 hour of rainfall duration time. After that, the ground water level continued to ascend as the rainfall duration time was getting longer. After rainfall, the ground water level was distributed at a certain depth, and the ground water level was gradually descending as time goes by. According to the slope stability analysis of the embankment considering the variation of the wetting front and the ground water level, the safety factor of slope was rapidly reduced as the rainfall began to infiltrate into the ground, and the minimum safety factor of slope was estimated after 24 hours of rainfall duration time. Meanwhile, the safety factor of slope was increased with regaining the matric suction in the ground after rainfall.

• Journal of Korea Water Resources Association
• /
• v.57 no.7
• /
• pp.471-479
• /
• 2024

Flood damage is becoming more serious due to the heavy rainfall caused by climate change. Physically based hydrological models have been utilized to predict stream water level variability and provide flood forecasting. Recently, hydrological simulations using machine learning and deep learning algorithms based on nonlinear relationships between hydrological data have been getting attention. In this study, the Long Short-Term Memory (LSTM) algorithm is used to predict the water level of the Seomjin River watershed. In addition, Climate Prediction Center morphing method (CMORPH)-based gridded precipitation data is applied as input data for the algorithm to overcome for the limitations of ground data. The water level prediction results of the LSTM algorithm coupling with the CMORPH data showed that the mean CC was 0.98, RMSE was 0.07 m, and NSE was 0.97. It is expected that deep learning and remote data can be used together to overcome for the shortcomings of ground observation data and to obtain reliable prediction results.

• Journal of the Korean GEO-environmental Society
• /
• v.22 no.12
• /
• pp.33-40
• /
• 2021

The deterioration of underground facilities, disturbance of the ground due to underground development activities, and changes in ground water can cause ground subsidence accidents in the urban areas. The investigation on the geotechnical and hydraulic factors affecting the ground subsidence accident is very significant to predict the ground subsidence risk in advance. In this study, an analysis DB was constructed through 3D ground modeling to utilize the currently operating geotechnical survey information DB and ground water behavior information for risk prediction. Additionally, using these results, the relationship between the actual ground subsidence occurrence history and ground conditions and ground water level changes was confirmed. Furthermore, the methodology used to visualize the risk of ground subsidence was presented by reconstructing the engineering characteristics of the soil presented according to the Unified Soil Classification System (USCS) in the existing geotechnical survey information into the internal erosion sensitivity of the soil, Based on the result, it was confirmed that the ground in the area where the ground subsidence occurred consists of more than 40% of sand (SM, SC, SP, SW) vulnerable to internal erosion. In addition, the effect of the occurrence frequency of ground subsidence due to the change in ground water level is also confirmed.

• Journal of the Korean Geotechnical Society
• /
• v.26 no.7
• /
• pp.147-159
• /
• 2010

The settlement prediction is very important in preloading method for a construction site on the soft ground. At the design stage, however, it is hard to predict the settlement exactly due to limitations of the site survey. Most of the settlement prediction is performed by a regression settlement curve based on the field data during construction. In Korea, hyperbolic method has been most commonly used to align the settlement curve with the field data, because of its simplicity and many application cases. The results from hyperbolic method, however, may differ by data selections or data fitting methods. In this study, the analyses using hyperbolic method were performed about the field data of $\bigcirc\bigcirc$ site in Pusan. Two data fitting methods, using an axis transformation or an alternative method which is a direct regression method, were applied with various data groups. If data was used only after the ground water level being stabilized, fitting results using both methods were in good agreement with the measured data. Regardless of the information about the ground water level, the alternative method gives better results with the field data than the method using an axis transformation.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.39 no.3
• /
• pp.128-137
• /
• 1997

In this study, examined influence of consolidation effect that had affected by location of pump inlet that was set collection well for drainage of pore water discharged by embankment on soft ground through the field test. The results of this study are summarized as follows; 1 Initial consolidation curve value were larger than theoritic value, the cause of these phenomena were thought influence of secondary consolidation and three dimensional strain of soft clay. 2. The settlement value of Hosino method was larger than that of Hyperbolic method, but settlement value of Hyperbolic method was accurate more than that of Hosino method in the prediction of settlement. 3. When pump inlet in collection well came down from GL+O.3m to GL-1.5m, settlement value increased about 10cm and when the ground water level was made insitu after pumping had completed , settlement was expanded about 7~8cm. So it is found that location change of pump inlet bad an influence on settlement remarkably. 4. If location of pump inlet in collection well for large scale estate or wide road site is lowered than original ground level, the settlement will be accelerated effectively, and at this stage automatic pump must be used in pumping.