• 제목/요약/키워드: settlement prediction

검색결과 264건 처리시간 0.025초

변형연화모델을 이용한 미고결 지반의 터널변형 (Tunnel Deformation in Shallow Unconsolidated Ground by Using Strain-Softening Model)

  • 서인식;김병탁
    • 한국산업융합학회 논문집
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    • 제10권2호
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    • pp.81-88
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    • 2007
  • In case of an urban tunnel, the displacement of ground base controls the tunnel design because it is built on shallow and unconsolidated ground many times. There are more insufficiency to describe the ground movement which coincides in the measured result of the situ because the design of an urban tunnel is dependent on the method of numerical analysis used to the existing elastic and elasto-plastic models. We studied about the prediction for the ground movement of a shallow tunnel in unconsolidated ground, mechanism of collapse, and settlement. Also this paper shows comparison with the existing elastic and elasto-plastic model using the unlinear analysis of the strain-softening model. We can model the real ground movement as the increasement of ground surface inclination or occurrence of shear band by using strain-softening model for the result of ground movement of an urban NATM tunnel.

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주거생활주기 모형 설정을 위한 이론적 접근 (A Theoretical Approach for Modeling of Housing Life Cycle)

  • 김대년
    • 한국주거학회논문집
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    • 제1권1호
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    • pp.37-48
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    • 1990
  • The objective of this study is to suggest a housing life cycle of Korean families which adds to the establishment of reasonable housing standards and to the prediction of fufure-oriented family housing behavior by reviewing published papers. Following model is suggested as a housing life cycle suitable to assess the family housing behavior in Korea. 1st stage : period of house searching 2nd stage : period of house changing 3rd stage : period of house stabilizing \circled1 size enlargement phase \circled2 quality improvement phase \circled3 stable settlement phase 4th siage : period of house contracting 5th stage : period of house depending Since the proposed model is hypothetical, it must be tested and modified by the extensive social survey research on the real housing event history.

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Single Surface 구성모델에 의한 유한요소 해석의 적용성 (Applicability of FEM Analysis by Single Surface Constitutive Model)

  • 이문수
    • 한국농공학회지
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    • 제37권2호
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    • pp.73-85
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    • 1995
  • This study aimes at investigating the applicability of single surface work - hardening model(7, 8) to clayey soils through FEM analysis. The comparison was carried out for the results between numericaL analysis and cubical triaxial tests in which confined stress was applied differently and 3-directional principal stress can be controlled. Furthermore, the results of the numerical analysis were compared with observed values of load test on the 2-dimensional model foundation composed of clayey soils. The agreement between nu- merical and observed values proved to be of high accuracy, which indicates that numeri- cal techniques developed during this study using the model can be used for the prediction of settlement, leteral displacement and pore water pressure of actual soft foundation of clayey soils.

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반복삼축압축실험을 통한 사질토의 소성변형 특성에 관한 연구 (Study on Plastic Deformation of Cohesionless Soil through Cyclic Triaxial Test)

  • 신은철;강현회;최찬용;양희생
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.1370-1376
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    • 2008
  • The structure of railroad or subway is that low fare transportation system of the large traffic volume. Like this structure is subjected to the cyclic load of moving vehicle. Consequently the result of the settlement analysis or plastic deformation prediction of railroad bed could be used as an important factor in safety of the railroad. The results of cyclic triaxial test were used in the numerical analysis of power model which Li and Selig(1994) developed. The soil samples were obtained from the construction site of railroad. Cyclic triaxial test was conducted with the variation of the magnitude of cyclic load and soil types. The large magnitude of plastic deformation in the railroad bed is caused of structure failure of the railroad.

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최근 일본 오사카만에 건설된 세개의 인공섬 (ARTIFICIAL ISLANDS RECENTLY CONSTRUCTED IN OSAKA BAY. JAPAN)

  • T.Akagi
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1992년도 가을학술발표회 논문집
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    • pp.11-26
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    • 1992
  • An attempt has been made to summarize some of the unique geotechnical problems encountered during construction of a few large man-made islands recently completed off the coast of Osaka Bay, Japan. Large settlements appear to be the most serious problem both during and after construction. Settlements due to consolidation of a thick layer of soft alluvial clay that constitutes seabed seem to virtually cease within a relatively short period of time when vertical drains are installed adequately prior to fill placement. Settlements due to compression of underlying thick diluvial deposits consisting of layers of stiff clays interbedded with coarse-grained soils, however, continue over a prolonged period of time and call for special provisions for structures built on the artificial islands to cope with relatively large future settlements. Although accurate settlement prediction is not possible, it is both technically and economically feasible, nevertheless, to construct large-scale islands. Partjcularly attractive and promising is creation of sizable new areas for various purposes, immediately adjacent to highly-developed, densely-populated cities situated along the coast such as those around Osaka Bay.

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Field experimental study for layered compactness of subgrade based on dimensional analysis

  • Han, Dandan;Zhou, Zhijun;Lei, Jiangtao;Lin, Minguo;Zhan, Haochen
    • Geomechanics and Engineering
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    • 제29권5호
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    • pp.583-598
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    • 2022
  • The Compaction effect is important for evaluating the subgrade construction. However, there is little research exploring the compaction quality of deep soil using hydraulic compaction. According to reinforcement effect analysis, dimensional analysis is adopted in this work to analyze subgrade compactness within the effective reinforcement depth, and a prediction model is obtained. A hydraulic compactor is then employed to carry out an in-situ reinforcement test on gravel soil subgrade, and the subgrade parameters before and after reinforcement are analyzed. Results show that a reinforcement difference exists inside the subgrade, and the effective reinforcement depth is defined as increasing compactness to 90% in the depth direction. Layered compactness within the effective reinforcement depth is expressed by parameters including the drop distance of the rammer, peak acceleration, tamping times, subgrade settlement, and properties of rammer and filler. Finally, a field test is conducted to verify the results.

EPS 거동 예측 모델의 적용성에 대한 연구 (A Study on the Application of Numerical Model to Predict Behaviour of EPS)

  • 천병식;유한규;임해식
    • 한국지반공학회지:지반
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    • 제12권6호
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    • pp.185-198
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    • 1996
  • EPS(Expanded Polystyrene)를 이용한 하중경감공법은 초경량재(20~30kg/m3)인 EPS를 본 연구는 보강토 토류벽체의 뒤채움재로서 폐 EPS 조각을 혼합한 경량의 성토재료를 개발, 활용하기 위한 기초연구로서, 우리나라에 광범위하게 분포하는 화강풍화토와 폐 EPS조각을 혼합한 경량성토재에 대해 공학적 특성파악을 위한 기본물성시험을 수행하였고, 또한 국내에서 판매되고 있는 두가지 대표적인 강성 및 연성 지오그리드 보강재에 대해 폐 EPS조각의 혼합비를 변화시 켜가며 실내인발시험을 수행하였으며, 이들 시험결과를 토대로 하여 폐 EPS조각 혼합경량토의 토질공학적 특성과 지오그리드-혼합경량토 사이의 마찰특성을 분석.평가하였다. 또한 본 연구에서는, 인장력 이외에도 다짐하중 및 상재하중 등 수직하중에 의한 압축력이 추가로 동시에 작용하는 경우의 지오그리드의 인장력-변형률 관계를 고려할 수 있는 마찰강도 산정방법을 제시하였으며, 이 방법을 토대로 하여 지오그리드-혼합토 사이의 마찰강도 평가시 적용가능한 보정계수 a1 및 a2 값의 범위를 제시하였다.

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대변형 압밀방정식의 수식화 (Numerical Formulation of Consolidation Based on Finite Strain Analysis)

  • 신호성;이승래
    • 한국지반공학회논문집
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    • 제29권6호
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    • pp.77-86
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    • 2013
  • 연약지반위에 성토를 할 경우 초기 비배수 상태 뿐만 아니라 압밀 과정 중에도 큰 변형이 발생한다. 기존의 미소변형률 이론은 변형률이 작고 초기의 기하학적인 형상이 변형과정 동안 변하지 않는다고 가정하므로 큰 변형이 유발되는 지반공학 문제들을 해석하기 위해서는 대변형 해석을 수행하여야 한다. 힘평형 방정식과 유체 연속방정식이 결합된 압밀지배 방정식을 Updated-Lagrangian 형태로 수식화하고, Jaumann stress rate을 이용하여 역학적 구성관계를 표현하였다. 그리고 Nagtegaal이 제안한 회전을 고려한 구성관계를 적용하여 Newton의 반복과정을 통한 해의 수렴성과 정확도를 향상시켰다. 개발된 대변형 압밀해석 프로그램을 검증하기 위하여 켄틸레버보와 이차원 압밀문제를 해석하였다. 수치해석 결과는 큰 변형률과 기하학적 회전을 포함하는 대변형 문제를 효과적으로 묘사할 수 있음을 보여주었다. 기존의 미소변형이론에 근거한 유한요소 프로그램은 제안한 방법을 통하여 대변형 해석 프로그램으로 용이하게 전환될 수 있다.

GIS 및 지구통계학을 이용한 실시간 통합계측관리 프로그램 개발 (Development of Real Time Monitoring Program Using Geostatistics and GIS)

  • 한병원;박재성;이대형;이계춘;김성욱
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.1046-1053
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    • 2006
  • In the large scale recent reclaiming works performed within the wide spatial boundary, evaluation of long-term consolidation settlement and residual settlement of the whole construction area is sometimes made with the results of the limited ground investigation and measurement. Then the reliability of evaluation has limitations due to the spatial uncertainty. Additionally, in case of large scale deep excavation works such as urban subway construction, there are a lot of hazardous elements to threaten the safety of underground pipes or adjacent structures. Therefore it is necessary to introduce a damage prediction system of adjacent structures and others. For the more accurate analysis of monitoring information in the wide spatial boundary works and large scale urban deep excavations, it is necessary to perform statistical and spatial analysis considering the geographical spatial effect of ground and monitoring information in stead of using diagrammatization method based on a time-series data expression that is traditionally used. And also it is necessary that enormous ground information and measurement data, digital maps are accumulated in a database, and they are controlled in a integrating system. On the abovementioned point of view, we developed Geomonitor 2.0, an Internet based real time monitoring program with a new concept by adding GIS and geo-statistical analysis method to the existing real time integrated measurement system that is already developed and under useful use. The new program enables the spatial analysis and database of monitoring data and ground information, and helps the construction- related persons make a quick and accurate decision for the economical and safe construction.

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침하에 의한 폐기물 매립지 최종복토층 HDPE의 영향에 관한 연구 (The Effects of HDPE by Landfill Settlements in the Final Cover System)

  • 문철환;이재영;전한용
    • 한국지반신소재학회논문집
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    • 제2권3호
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    • pp.11-18
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    • 2003
  • 최종복토의 설계에 있어 가장 중요한 요소 중 하나는 매립지 내부로 우수의 침투를 제한하는 것이다. 우수의 침투는 침출수 발생량을 증가시켜 침출수 처리 비용의 증가에 따른 매립지 운영 비용을 증가 초래한다. 따라서, 매립지의 최종복토층은 우수의 침투를 최소화하기 위해 단독의 다짐점토층 또는 HDPE와 다짐점토층의 복합으로 구성된 차단층을 포설하도록 되어 있다. 그러나 다짐점토층과 HDPE는 매립 폐기물의 분해에 의해 발생하는 침하에 의해 손상이나 파손이 발생할 우려가 있다. 따라서 본 연구는 매립 종료 후 침하에 따른 폐기물 매립지 최종복토층 HDPE의 영향에 대해 평가하고자 수행되었다. 현장시험시공과 lysimeter test, 최종복토 후 침하 예측 결과 최종복토층의 HDPE는 침하에 의한 영향을 크게 받지 않는 것으로 나타나 침하에 대해 안정하다고 할 수 있다.

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