• Journal of the Korean GEO-environmental Society
• /
• v.18 no.9
• /
• pp.11-18
• /
• 2017

Numerical analysis method for prediction of pile behaviour characteristics has widely been used in detail design process before construction because field static loading test requires high cost. However, the reliability verification of numerical analysis of result is not permitted compare with field test. In this study, to verify the numerical analysis results, pile behaviour prediction was compared with field static loading test results. For exact analysis of interaction between pile and ground, soil investigation and in-situ test such as boring, SPT and bore-hole shear test were performed before pile static loading test. During the static loading test, pile behaviour characteristics were analyzed under every loading condition. After static pile loading test, numerical analysis was carried out under same condition with static pile loading test. In the numerical analysis, to apply same loading condition with each loading condition in the field test and to compare with between the results of numerical analysis, the field test results for reliability were verified with the results of numerical analysis.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2002.03a
• /
• pp.83-92
• /
• 2002

지반조건은 구조물의 지진거동에 매우 큰 영향을 미치고 성능에 기준한 내진설계에 중요한 요소이다. 이 논문에서는 지진에 의한 지반의 비선형성을 포함한 지반의 비선형성이 구조물의 탄성지진거동에 미치는 영향을 지반 구조물 일괄해석 유한요소법과 지반의 비선형성을 구현하기 위해 Ramberg-Osgood 토질모델에 대한 근사 선형 반복해석 법으로 연구하였다. 연구는 말뚝기초의 유무를 고려한 주기가 변하는 선형 단자유도계에 지표에서 기록된 1940년 El Centro 지진을 적용하여 수행하였다. 연구결과에 의하면 연약지반의 비선형 특성 영향이 구조물의 탄성 지진거동에 매우 중요하고, 성능에 기준한 지반의 비선형성을 고려한 구조물의 내진설계가 필요하다는 것을 잘 보여주고 있다.

• Geotechnical Engineering
• /
• v.25 no.9
• /
• pp.20-29
• /
• 2009

• Proceedings of the Korean Geotechical Society Conference
• /
• 1998.10a
• /
• pp.283-290
• /
• 1998

• The Journal of Engineering Geology
• /
• v.30 no.2
• /
• pp.131-145
• /
• 2020

The construction on these flimsy ground, activation of unsymmetrical surcharges, can often cause of the embankment road lateral flow or the destruction of the activities. In this study, the stability of the abutment pile foundation installed on soft ground and its behavior has been evaluated. The behavior of the abutment pile foundation under lateral flow was studied by verifying the behavior and reinforcement effects of the abutment pile foundation of previous studies about horizontal loads acting on the pile due to the lateral flow of the ground by performing finite element analysis. As a result of the consolidation analyses, the undrained cohesion or the strength of the soft ground, was increased by about 1.1 to 1.8 times by the increase in the strength of the soft ground according to the degree of consolidation. It is deemed reasonable to use 3.8 cm of the allowable displacement both economically and constructively, but considering the importance of the structure and the uncertainty of the ground, measurement shall be carried out during construction and thorough safety management of the lateral flow should be done.

• Journal of the Korean GEO-environmental Society
• /
• v.2 no.4
• /
• pp.63-72
• /
• 2001

As construction cases on soft ground are increasing, the necessity of ground improvement is also increasing. Granular pile is one of the methods for soft clay and for loose sandy soil. In our country, SCP(Sand Compaction Pile) method using sand material has been mainly used to improve soft ground, but Granular pile with crushed-stone was not used much. However, alternative material such that crushed-stone is needed to substitute for sand due to the environmental and economical problems. In this study, staged load test and consolidation test were performed in the laboratory to observe the behavior of soft ground improved by Granular pile. In order to evaluate the characteristics such as bearing capacity, drainage, and settlement, sand and crushed-stone were applied as each pile material. The test results show that crushed-stone has higher bearing capacity and less settlement than those of sand under similar pore water pressure condition. Therefore, crushed-stone is determined to be appropriate as substitute for sand.

• Journal of the Korean GEO-environmental Society
• /
• v.13 no.4
• /
• pp.61-69
• /
• 2012

A high rock embankment by means of phased dynamic compaction has hardly carried out in Korea. Settlement of each layer is measured in order to verify the settlement behavior of dynamically compacted high rock embankment. A high rock embankment is generally constructed by dividing into several sub-embankments. Such a sub-embankment and dynamic compaction may induce an increase of pressure at the lower part of embankment and cause a different behavior of ground from initial status. In this study, settlement of a high rock embankment is estimated using a hyperbolic model taking into construction history. The results from prediction are compared with those obtained from field measurements. And second creep settlement is predicted using pre-loading test.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.586-591
• /
• 2004

매년 발생되는 절토사면의 붕괴를 사전에 방지하기 위하여 절토사면에 상시 계측시스템을 설치하고 지반의 거동분석을 실시한다. 본 현장의 절토사면 붕괴 규모와 메카니즘을 분석하고 계측 결과와 상호 비교 분석한다. 본 현장은 상시계측시스템 운용 확대 실시에 따른 시험 설치 현장으로 2003년부터 운용 중에 있다. 계측결과에 의하면 강우량과 지반의 거동이 밀접한 관계가 있는 것으로 사료된다. 본 현장의 경우 크게 3번의 지반이동이 있었으며 현재는 안정화 단계에 있는 것으로 사료된다. 그러나, 향후 동절기의 외분 온도 변화와 동반하여 지반의 변동이 우려됨으로 인하여 지속적인 관찰과 자료 분석이 수행되어야 할 것으로 본다.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.6 no.2
• /
• pp.51-61
• /
• 2002

In this research, a numerical algorithm is developed for the response analysis of burined pipelines considering longitudinal permanent ground deformation(PGD) due to liquefaction induced lateral spreading. Buried pipelines and surrounding soil are modeled as continuous pipelines using the beam elements and a series of elasto-plastic springs represented for equivalent soil stiffness, respectively. Idealized various PGD patterns based on the observation of PGD are used as a loading configuration and the length of the lateral spread zone is considered as loading parameter. Numerical results are verified with other research results and efficient applicability of developed procedure is shown. Analyses are performed by varying different parameters such as PGD pattern, pipe diameter and pipe thickness. Through these procedures, relative influences of various parameters on the response of buried pipeline subject to longitudinal PGD are investigated.

• Geotechnical Engineering
• /
• v.12 no.6
• /
• pp.127-138
• /
• 1996

The in-situ consolidation behavior of drainage system-installed deposits has three dimensional characteristics. Therefore, for an approximate 2-D plane strain consolidation analysis, it is necessary to convert the 3-D spatial flow of actual cases into the laminar flow simulated by the 2-D plane strain model. . In this paper, in order to properly model the effect of three dimensional characteristics, an equivalent and efficient model has been applied in a finite element technique for the analysis of the drainage system-installed soil deposits. The equivalent two dimensional model involves equivalent permeabilities and drainage widths. To validate the equivalent two dimensional model, three dimensional analyses were per formed by using the ABAQUS program and the results of 3-D analyses were compared with those of the 2-D analyses. By using the proposed equivalent model, one may be able to appropriately predict the consolidation behavior of drainage system-installed soft deposits.