• Wind and Structures
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• 제32권5호
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• pp.453-469
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• 2021

Snow accumulation on the road frequently induces a big traffic problem in the cold snowy region. Accurate prediction on snow distribution is fundamental for solving drifting snow disasters on roads. The present study adopts the transient method to simulate the wind-induced snow distribution on embankment based on the mixture multiphase model and dynamic mesh technique. The simulation and field measurement are compared to confirm the applicability of the simulation. Furthermore, the process of snow accumulation is revealed. The effects of friction velocity and snow concentration on snow accumulation are analyzed to clarify its mechanism. The results show that the simulation agrees well with the field measurement in trends. Moreover, the snow accumulation on the embankment can be approximately divided into three stages with time, the snow firstly deposited on the windward side, then, accumulation occurs on the leeward side which induced by the wake vortex, finally, the snow distribution reaches an equilibrium state with the slope of approximately 7°. The friction velocity and duration have a significant influence on the snow accumulation, and the vortex scale directly affected the snow deposition range on the embankment leeward side.

• 한국터널지하공간학회 논문집
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• 제23권1호
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• pp.37-45
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• 2021

터널의 갱구부는 토피가 얕고 지반의 아칭효과가 발휘되기 어렵기 때문에 터널 시공 시 주의가 필요한 구간이다. 공용 중인 터널 갱구부 상부에 추가적인 성토가 이루어진다면 터널 안정성을 크게 저해할 수 있다. 따라서 본 연구에서는 터널 상부의 추가 성토에 따른 터널 안정성을 검토하고자 지반조건별로 성토 높이에 따른 수치해석을 수행하였다. 해석 결과 5등급 암반에서 성토 높이가 12 m 이상인 경우에는 숏크리트의 허용 휨압축응력, 록볼트의 허용 축력을 초과하는 것으로 나타났다. 발생되는 변위와 소성영역의 범위, 지보재의 상태를 종합적으로 고려할 때 터널 갱구부 상부에 추가 성토되는 높이가 10 m를 초과하는 경우에는 터널 안정성이 크게 저해되는 것으로 판단된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 연약지반처리위원회 학술세미나
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• pp.79-92
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• 2000

In this paper, comparison of the observed and the predicted ground deformations due to the construction of road embankment with peck drain near the construction site was made. Measurement of the ground deformation at the gasoline stand due to the construction of road embankment was made and it was compared with the predicted deformation results of Finite Element Method analysis made with Elasto-plastic and Elastic visco-plastic models. A well agreement was obtained between the measured and predicted ground deformations.

• 한국농공학회논문집
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• 제55권2호
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• pp.1-8
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• 2013

This study was performed for the purpose of analyzing the effect of tide on the stress-strain behavior in the boundary surface of sea dike embankment. Tide is a dynamic condition, but there are not suitable numerical models to solve the dynamic embankment condition caused by tide. So the analysis was simplified to quasi dynamic as follow. First, seepage by tide was analyzed according to elapsed time, and the results of the analysis at every hour during one periodic cycle time of 12 hours were applied to the pore water pressure conditions of stress-strain analysis with hyperbolic model by Duncan and Chang. The place at which maximum shear strain took place in the analysis result moved up and down repeatedly along the boundary of the dredged sand fill section and the crashed stone filter section. The value of maximum shear strain was large at high water level of tide. This result means that contraction and relaxation occur in turn repeatedly at every specific position along the boundary, and the repeated action compact loose position with sand moved down from the upper position by gravity. The experiment with the small sea dike model showed the result consistent with the numerical analysis. The surface of sea side on the dike collapsed at high water level after a couple of repetition of the rising and falling of water.

• 농업과학연구
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• 제50권3호
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• pp.469-484
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• 2023

In this study, three types of structures-stepped gabion retaining walls, vertical gabion retaining walls, and parapets-were installed on the dam floor crest to prevent the overflow of deteriorative homogeneous reservoirs. The acceleration response, displacement behavior, and pore water pressure ratio behavior were compared and evaluated using shaking-table model tests. The experimental conditions were set to 0.154 g in consideration of the domestic standard and the seismic acceleration range according to the magnitude of the earthquake, and the input waveform was applied with Pohang, Gongen, and artificial earthquake waves. The acceleration response according to the design ground acceleration increased as the height of the embankment increased, and the observed value were larger in the range of 1.1 to 2.1 times the input acceleration for all structures. The horizontal and vertical displacements exhibited maximum values on the upstream slope, and the embankment was evaluated as stable and included within the allowable range for all waveforms. The settlement ratio considering the similarity law exhibited the least change in the case of the parapet structure. The amplification ratio was 1.1 to 1.5 times in all structures, with the largest observed in the dam crest. The maximum excess pore water pressure ratio was in the range of 0.010 - 0.021, and the liquefaction evaluation standard was within 1.0, which was considered very stable.

• 한국구조물진단유지관리공학회 논문집
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• 제14권6호
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• pp.215-219
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• 2010

본 연구에서는 제방 축조재료로 사용되는 낙동강 모래의 응력-변형 거동특성 파악을 위하여, 삼축압축시험 등을 포함한 실내시험을 실시하였고, 조립재료의 거동 표현에 적합한 개별요소방법을 적용한 수치 모델링을 실시하였다. 개별요소해석은 삼축압축시험 과정을 모델링하였으며, 이때 이용된 미시물성치는 물성치 보정과정을 통해 산정 되었다. 특정 구속압조건을 만족시키는 미시 물성치의 산정이 가능하다면, 이 미시물성치의 이용을 통해 다른 구속압조건 및 응력재하 조건에서의 거동예측에 있어, 개별요소방법이 매우 효과적으로 이용될 수 있음을 알 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.967-975
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• 2009

In order to control differential settlement and to secure the safety of super structure on a high rock embankment the designed static compaction is changed with dynamic compaction and piled raft method. The parameters for dynamic compaction design are obtained from a pilot test. In addition, numerical analyses are also carried out to figure out the length and quantity of piled raft that can restraint the differential settlement within allowance range.

• 대한토목학회논문집
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• 제37권5호
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• pp.787-799
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• 2017

저수지 제체 내 수로 구조물과 흙 접촉면의 장기적인 누수가 제체 파괴의 주원인 중의 하나 임에도 불구하고 이에 대한 연구는 미미한 실정이다. 배수통관과 같은 구조물이 부분 파손되어 누수가 발생하는 경우 외형적으로 관측하기 곤란하고 파이핑 등에 의한 제체 손상 우려가 있어 이에 대한 연구가 필요하다. 본 연구는 저수지 제체를 관통하는 배수 통관이 부등침하 등으로 인해 통관 일부가 파손되어 누수가 발생하는 경우 저수지의 제체 형태를 코어형 단면과 균일형 단면으로 구분하여 수위변화에 따른 2차원 침투해석을 수행하였다. 연구결과 저수지 등의 제체를 관통하는 배수 통관으로의 누수가 발생 할 경우 통관 하부보다는 상부가 파손되어 누수가 되는 경우가 파이핑 발생 가능성이 크며, 특히 제체 하류측에서 누수가 발생하는 경우 제체 중심 코어부의 존재는 제체 안정 유지에 도움을 주고 있다고 판단된다. 또한 저수지 제체 내부 간극수압의 급격한 감소가 관측되면 파이핑 발생 우려에 대한 심도 있는 고려가 필요할 것으로 사료된다.

• 한국농공학회논문집
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• 제57권3호
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• pp.55-63
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• 2015

Embankment of agricultural reservoir started by four major rivers project. Most agricultural reservoirs must insure the agricultural water, they need must be ensured stability of embankment. Recently, there is a growing interest in seismic stability of structure by earthquake. Results of evaluation of the structural stability through seismic vibration test and numerical analysis, maximum displacement and the maximum acceleration is a similar trends. Appeared by increasing occurrence of the value of the displacement and acceleration of the structure with the result long period wave type in accordance with the seismic wave in the case of seismic waves, which shows the results of similar tendency as long period wave type consists of waveform seismic acceleration. Model test and numerical analysis results with in order to increase embankment agricultural reservoir, the displacement was found to ensure it is displayed within one percentage structural stability of the embankment.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.381-388
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• 2002

A series of centrifuge model tests were performed to investigate the behavior of piled bridge abutment subjected to lateral soil movements induced by the construction of approach embankment. In these tests, both the depth of soft clay and the rate of embankment construction are chosen as key parameters to examine the effects on lateral soil movements. The depth of soft clay layer varies from 5.2 m to 11.6 m, and the rate of embankment construction has two types of staged construction(1m/30days, 1m/15days) and instant construction. It is shown that, the distribution of lateral flow induced by stage embankment construction has a trapezoidal distribution. And practical guidelines to check the possibility of some lateral movement of piled abutment were investigated. The validity of the proposed guidelines by centrifuge test was compared with the observed performance by lateral movement index, F(Japan Highway Public Corporation) and modified I index(Korea Highway Corporation). Based on the results obtained, the critical values of F and modified I, as a practical guidelines, are proposed to 0.03 and 2.0, respectively.