• Title/Summary/Keyword: Primary settlement

Search Result 102, Processing Time 0.022 seconds

An Implicit Stress Integration for the Constitutive Relationship of Clays (점토의 구성관계에 대한 내재적인 응력적분)

  • 오세붕
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1998.10a
    • /
    • pp.92-98
    • /
    • 1998
  • Nonlinear finite element analyses of one dimensional consolidation problem were performed using an anisotropic hardening constitutive model. For the analyses, the anisotropic hardening elasto-plastic constitutive model based on the generalized isotropic hardening(GIH) rule was implemented into a nonlinear finite element analysis program, PLASTIC. In order to preserve the accuracy of the finite element solution for nonlinear problems, an implicit stress integration algorithm was employed. A consistent tangent moduli could also ensure the quadratic convergence of Newton's method. As a result, the nonlinear solution was accurately calculated and was converged to be asymptotically quadratic. In a consolidation problem, the relationship between load and settlement and between settlement and time vertical was analyzed comparing with results using the Cam-clay type model and the final consolidation settlement and the duration of primary consolidation could be evaluated rigorously using the GIH constitutive model.

  • PDF

A Study on Settlement of Commercial Disputes between the South and the North of Korea (남북한 상사분쟁의 해결에 관한 연구)

  • Kim Sang-Ho
    • Journal of Arbitration Studies
    • /
    • v.16 no.2
    • /
    • pp.3-49
    • /
    • 2006
  • The purpose of this paper is to make research on the settlement mechanism of the commercial disputes between the South and the North of Korea. Also, this paper is to make research on the south-north Korea's cooperative tasks to promote the disputes settlement, including the operation and management of the South-North Arbitration Commission as well as the enactment of the South-North Arbitration Rules. To realize the spirit of the South-North Joint Declaration of June 15, 2000, the Authorities concerned of the South and the North of Korea have reached an agreement titled 'Agreement on Settlement Procedure of Commercial Disputes' on December of the same year. As the follow-up measures of the said Agreement, the South-North Authorities have signed an another agreement called 'Agreement on Organization and Administration of the South-North Arbitration Commission' on October, 2003, which is becoming vital importance for settlement of the commercial disputes between south and north Korea including the Gaeseong Industrial Complex. Gaeseong, a city surrounded by the North Korean military and a symbol of inter-Korean tensions, is now turning into a peace zone where thousands of North and South Koreans are working side by side. The Gaeseong Industrial Complex project, driven by the logic and economic necessity of cooperation, has been steadily moving forward since the North designated it as a special economic zone and has enacted related laws and regulations for its development. Under the situation, the matter of primary concern is how to organize and conduct the Arbitration Commission for the prompt and effective settlement of the south-north commercial disputes. First of all, the South-North Authorities should recognize that the availability of prompt, effective and economical means of dispute resolution such as arbitration and mediation to be made by the Arbitration Commission would promote the orderly growth and encouragement of the south-north trade and investment. In this connection, the Korean Commercial Arbitration Board(KCAB) should be designated as the arbitral institution of the south Korean side under the Agreement on Organization and Administration of the South-North Arbitration Commission. The KCAB is the only authorized arbitral organization in South Korea to settle all kinds of commercial disputes at home and abroad.

  • PDF

Analysis of load-settlement behaviour of shallow foundations in saturated clays based on CPT and DPT tests

  • Mir, Mouna;Bouafia, Ali;Rahmani, Khaled;Aouali, Nawel
    • Geomechanics and Engineering
    • /
    • v.13 no.1
    • /
    • pp.119-139
    • /
    • 2017
  • Static Penetration Test (CPT) and Dynamic Penetration Test (DPT) are commonly used in-situ tests in a routine geotechnical investigation. Besides their use for qualitative investigation (lithology, homogeneity and spatial variability), they are used as practical tools of geotechnical characterization (resistance to the penetration, soil rigidity) and modern foundation design as well. The paper aims at presenting the results of an extensive research work on the evaluation of the 1D primary consolidation settlement of saturated clayey soils on the basis of the CPT or DPT tests. The work is based on an analysis of the correlations between the tip resistance to penetration measured in these tests and the parameters of compressibility measured by the compressibility oedometer test, through a local geotechnical database in the northern Algeria. Such an analysis led to the proposal of two methods of calculation of the settlement, one based on the CPT test and the other one on the DPT. The comparison between the predicted settlements and those computed on the basis of the oedometer test showed a good agreement which demonstrate the possbility to use the CPT and DPT tests as reliable tools of computation of foundation settlements in clayey soils.

Geotechnical Engineering Characteristics and Consolidation Settlement Estimation of Waste Lime Landfill (폐석회 매립지반의 지반공학적 특성 및 압밀침하량산정)

  • Shin, Eun-Chul;Lee, Ae-Young
    • Journal of the Korean Geosynthetics Society
    • /
    • v.15 no.4
    • /
    • pp.1-8
    • /
    • 2016
  • The purpose of this study is to examine the consolidation characteristics of waste landfill from sodium carbonate production. The waste lime is a byproduct from the production of soda ash. The consolidation settlement of waste lime landfill was determined for waste lime specimen which obtained from the field boring. The consolidation tests are conducted for determination of the primary and secondary consolidation settlements. The waste lime is classified as an organic soil with high plasticity. As a result of an organic content test, the contents of organic matter in waste lime is much higher than that of normal clay. Finally, the total consolidation settlement of waste lime landfill is calculated by using a theoretical method and computer program for the given initial void ratio, compression index, and embankment height.

Effect of PBD to improve soft marine sedimentary ground

  • Jeong, Jin-Seob;Hwang, Woong-Ki;Jeong, Choong-Gi;Kim, Tae-Hyung
    • Journal of Navigation and Port Research
    • /
    • v.33 no.2
    • /
    • pp.119-125
    • /
    • 2009
  • The effect of plastic board drains (PBDs)on ground improvement was checked out considering three crucial factors: ground settlement, undrained shear strength, and residual water head. First, the settlement analysis including initial settlement induced by reclamation of sand mat was conducted by back calculation analysis with measured data. Its result showed toot the PBDs used for this site worked well on improving soft ground. Secondly, the undrained shear strength was investigated by laboratory and in-situ tests including unconsolidated-undrained triaxial compression (UU) tests, unconfined compression tests, in-situ vane tests, and cone penetration tests. From the test results, they showed that the undrained shear strength of the improved ground by PBDs was significantly increased as well as the strength increasing ratio especially $10{\sim}15m$ below the ground surface on site. Thirdly, the residual water head measurement from the in situ dissipation test was found the same as the static water head, which indicated primary consolidation was completed and the effect of soil improvement with PBDs can be confirmed.

A Primary Study on the Location and Size of Railway Station Facilities (철도 역시설의 입지와 규모에 관한 기초 연구)

  • 문대섭;이경철;정병현
    • Proceedings of the KSR Conference
    • /
    • 2002.05a
    • /
    • pp.116-121
    • /
    • 2002
  • This primary study has some bounds md limits owing to the descriptive reviews but not detailed analyses. However, 1 tried to do the comparative analyses and case studies about location and size of rail station for future efficient use of spatial structure. Therefore, I reviewed the location of railway station and some design standards of railway station facilities by type (high speed rail, conventional rail and urban rail), and also, suggested future direction for rail station as the core of city development relating with urban structures and human settlement system reformation.

  • PDF

Consolidation Settlement of Capped Sediment (II): Advective Transport of Pore Water and Analytical Prediction of Settlement (캡이 설치된 퇴적층의 압밀 침하 (II): 간극수의 이동 및 침하의 해석적 예측)

  • Kim, Tae-Hyung;Hong, Won-Pyo;Moo-Young, Horace-K
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.3
    • /
    • pp.39-44
    • /
    • 2003
  • Centrifuge test was conducted to simulate the effects of consolidation settlement of capped contaminated marine sediment. A fluorescent dye was used to monitor the movement of pore water through the cap layer. Dye tracer study clearly showed the consolidation induced advective transport of contaminants. Thus, the capping layer must be appropriately designed to reduce the effects of consolidation induced advective transport. The results from the centrifuge test were compared to predictions made by the Primary consolidation, Secondary compression, and Desiccation of Dredged Fill (PSDDF) computer program, which can qualitatively estimate the consolidation settlement of capped marine sediment. Although PSDDF approximated closely the secondary compression in the centrifuge test (i.e., compare data points from 18 to 25 prototype years), the maximum deviation between centrifuge test result and PSDDF prediction was 20 % about prototype time 6 years. Thus, designers should utilize PSDDF consolidation settlement results with caution.

Analysis of the Long-term Settlement Behavior Due to the Additional Embankment on the Waste Lime Landfill in Public Waters Reclaimed Land (공유수면 매립지내 폐석회 매립시설의 추가성토에 따른 장기침하 거동 분석)

  • Kang, Jeong Ku;Yi, Yeun Jeung
    • Journal of the Korean Geosynthetics Society
    • /
    • v.21 no.2
    • /
    • pp.1-9
    • /
    • 2022
  • Recently, the reclamation of public waters has been on a downward trend due to environmental problems, but there is a limitation to evaluating environmental characteristics index uniformly. In this study, the stability of settlement behavior on public waters reclaimed land was analyzed using the experimental test. From the primary consolidation influence factors, the characteristics of the waste lime was similar that of clay in process of consolidation. Assuming that the waste lime landfill is the layer reinforced with thin geosynthetic reinforcement, the settlement was predicted by calculating the amount of increase using the Westergaard method. As a result of predicting settlement with degree of consolidation, it was found that the increase in stress was reduced by 40% when the surface layer of the soft ground was reinforce with geotextiles compared to the case where it was not reinforced. In addition, the consolidation behavior characteristics of clay and waste lime were compared using the correlation between the plasticity index and internal friction angle of waste lime. Since the waste lime in the public process of consolidation, it was predicted that long-term settlement will increase further.

Numerical Evaluation of Settlement Reducing Effect by Partial Reinforcement of Rock Fill (수치해석을 통한 암성토 부분보강의 침하억제 효과 평가)

  • Lee, Su-Hyung;Choi, Yeong-Tae;Han, Jin-Gyu ;Gu, Kyo-Young
    • Journal of the Korean Geotechnical Society
    • /
    • v.39 no.11
    • /
    • pp.23-31
    • /
    • 2023
  • The escalating settlements observed in concrete slab tracks pose a significant challenge in Korea, raising concerns about their adverse impact on the safe operation of high-speed railways and the substantial costs involved in restoration. A primary contributor to these settlements is identified as the utilization of rock materials sourced from tunnel construction, incorporated into the lower subgrade without the requisite soil mixing to achieve an appropriate particle size distribution. This study employs numerical analysis to evaluate the efficacy of partial reinforcement in reducing settlements in rock-filled lower subgrades. Column-shaped reinforcement areas strategically positioned at regular intervals in the lower subgrade induce soil arching in the upper subgrade, leading to a concentration of soil loads on the reinforced areas and consequent settlement reduction. The analysis employs finite element methods to investigate the influence of the size, stiffness, and spacing of the reinforced areas on settlement reduction in the lower subgrade. The numerical results guide the formulation of an optimal design approach, proposing a method to determine the minimum spacing required for reinforcements to effectively limit settlements within acceptable bounds. This research contributes valuable insights into addressing the challenges associated with settlement in concrete slab tracks, offering a basis for informed decision-making in railway infrastructure management.

A Study on the Prediction of Long-Term Settlement by the Modified Hyperbolic Method (수정된 쌍곡선 법을 이용한 장기 침하량 예측)

  • Yoo, Han-Kyu;Kim, Jong-Hee
    • Journal of the Korean Geotechnical Society
    • /
    • v.16 no.3
    • /
    • pp.163-172
    • /
    • 2000
  • 최종침하 예측기법들은 분석상 간단명료하고 경제적인 기법이라 현장에서 널리 이용되고 있지만, 현장계측상의 문제들이 다분히 있는 실측치에 크게 의존함으로써 설계단계에서 침하량예측에 분석가의 주관적 판단이 큰 변수로 작용할 수 있으므로 객관성이 결여되는 결점을 안고 있다. 그 중 쌍곡선법(Hypervolic Method)이 가장 널리 쓰이고 있지만, 현장 계측치에 따라 가정 기본식의 선형성이 다소 뚜렷하지 않아 분석가에 따라 해석결과가 다르게 나타날 수 있으므로, 기술 적용상의 어려움과 경제적 비용을 더욱 가중시키는 결과를 초래할 수 있다. 따라서, 본 연구에서는 현장 계측자료 분석에 있어서 대표적으로 널리 적용되고 있는 쌍곡선법의 기본 가정식의 선형성 문제에 주안점을 두어 기본 가정식의 선형성을 확보하고, 그 선형구간을 확장한 새로운 침하예측기법을 제안하였다. 성토완료 직후의 현장 자료를 배수재가 설치된 지역과 배수재가 설치되지 않은 지역으로 구분하여 최종 1차 압밀침하량, 수직압밀계수 등을 기존예측기법 및 현장계측자료와 비교 검토하여 제안된 침하예측기법의 적용성을 검증하였다.

  • PDF