• Title/Summary/Keyword: wall reinforcement

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Evaluation of Local Damage of SC Wall using Local Collision Simulation (국부충돌해석에 의한 SC벽체의 국부손상 평가)

  • Woo, Dong In;Chung, Chul Hun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.2
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    • pp.265-274
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    • 2015
  • The structural safety of nuclear power plant against impact from aircraft crash has been performed so far in two viewpoints such as local behavior and global behavior, and the local behavior has been evaluated using local damage evaluation formulas suggested based on the results of experimental data of RC (Reinforcement Concrete) wall. However, few data have been collected from recent research to evaluate the local behavior and damage of SC (Steel plate reinforced Concrete) wall, which is recently applied to the newly designed nuclear power plant. In this study, local damages of SC wall and RC wall against an idealized aircraft engine projectile impact are evaluated through FE simulation analyses with various wall thicknesses and steel ratio. Through analysis of local collision simulation results of SC and RC wall, the penetration depth of SC wall and RC wall are compared.

Behavior of Mechanically Stabilized Earth Retaining Walls with Different Construction Sequence (시공과정에 따른 보강토 옹벽의 거동 특성)

  • 유충식;이광문
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.10a
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    • pp.473-480
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    • 1999
  • This paper presents the results of a parametric study on the behavior of mechanically stabilized earth retaining wall. It has been recognized that the currently available design guidelines, which is base on the limit equilibrium approach, cannot properly account the interaction effect between the components, construction sequence, and foundation settlement which may impose a significant influence on the wall behavior. A parametric study using finite element analysis was performed to investigate the behavior of MSE wall under different construction conditions and the applicability of the current design approach. In the parametric analysis, the effects of the construction sequence, the surcharge, and the foundation stiffness were studied and a detailed finite element modeling for various components of the system were employed. The results, such as wall displacement and earth pressure distributions, reinforcement forces, vertical stress distribution were then thoroughly analyzed to investigate the effect of construction details on the wall behavior.

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Troubles and Countermeasures of Geogrid-Reinforced Earth Wall (지오그리드 보강토 옹벽의 설계/시공에 따른 문제점과 대책방안)

  • 조삼덕
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.10a
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    • pp.315-321
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    • 2001
  • Since 1984, block-type reinforced earth wall with geogrid reinforcement has been widely used for retaining wall applications till now in Korea. The use of geogrid as a reinforcement in the reinforced earth wall is steadily increased in an amount over 1,500,000㎡ in a year However, still need exists that some problems in design and construction practices should be made to review, Therefore, this paper reviewed reasonable criteria for selection of backfills, design details considering the effect of the upper soil slope on reinforced earth wall, horizontal displacement of facing block during compaction, and the damage of geogrid reinforcements on the edge part of facing block. Finally, alternative methods of measures on those problems are proposed.

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Current State and Technical Development of Geosynthetics-Reinforced Earth Wall (토목섬유 보강토옹벽의 기술현황 및 개발동향)

  • Cho, Sam-Deok;Lee, Kwang-Wu
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.141-157
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    • 2008
  • Since 1984, block-type reinforced earth wall with geogrid reinforcement has been widely used for retaining wall applications till now in Korea. The use of geogrid as a reinforcement in the reinforced earth wall is steadily increased in an amount over $6,500,000m^2$ in a year. However, still need exists that some problems in design and construction practices should be made to review. Therefore, this paper reviewed current state and development items of geosynthetics-reinforced earth wall technology on design and construction point of view.

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The Evaluation of Pullout Resistance and Installation Damage according to the Shape of Flexible Strip Reinforcement (신장형 띠형 보강재의 형상에 따른 인발저항 및 시공성능 평가 실험 연구)

  • Jeoung, Jaehyeung;Kim, Jaehong
    • The Journal of Engineering Geology
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    • v.31 no.3
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    • pp.321-332
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    • 2021
  • Though development of reinforced earth wall is on the rise recently, safety verification for various methods remains behind which has caused the problems including collapse after installation. This study aims to evaluate the field applicability of the shape of flexible strip reinforcement according to pullout resistance test and field damage test. The test specimens were 3 shape of reinforcement, the typical flexible band reinforcement, developed luged band reinforcement, and band type reinforcement made by cutting geogrid. It was found that reinforcement of type have strengths and weaknesses, respectively. The best type of flexible strip reinforcements can be selected, if the conditions are considered with the installation conditions of the reinforcing earth retaining wall and the particle size of the backfill materials.

The Comparative Experiment of Geogrid Reinforcement Types with Construction Stage on Segmental Retaining Walls (블록식 보강토 옹벽에서의 시공단계별 보강재 타입에 따른 거동비교)

  • Lee, Sung-Hyouk;Lee, Jin-Wook;Choi, Chan-Yong
    • Journal of the Korean Geosynthetics Society
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    • v.11 no.4
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    • pp.1-8
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    • 2012
  • In this study, the earth pressure, displacement and strain were compared with reinforcement types at segmental retaining wall through full scale model test. The test results found that the measurement of earth pressure and displacement at wall for the fully reinforced retaining wall are different from those for the partly reinforced retaining wall. The analyses of these results would suggest that the used of geoogrid allowed the vertical earth pressure and displacement at wall to be reduced. The horizontal earth pressure in upper and lower part of wall can change with reinforcement type and earth deformation and were larger than the active and the rest pressure. Also, the lateral earth pressure and displacement of wall have a very high a correlation. It was found that the strain contour distribution of reinforcements was occurred a large strain at cental part of wall in segmental retaining wall system.

Numerical Investigation on Behavior of Back-to-Back Reinforced Earth Wall (Back-to-Back옹벽의 거동에 관한 수치 해석적 연구)

  • Yoo, Chung-Sik;Kim, Jae-Wang
    • Journal of the Korean Geotechnical Society
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    • v.25 no.12
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    • pp.131-142
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    • 2009
  • Geosynthetic reinforced soil walls are well recognized alternatives to conventional retaining walls due to many advantages in terms of ease of construction, economy, and aesthetics, among others. In recent years, the use of back-to-back (BTB) geosynthetic reinforced soil walls has been increasing for roadway and railway construction. However, there are insufficient studies concerning the behavior of BTB type geosynthetic reinforced soil walls. In this study a series of finite element analysis were performed for BTB walls with various wall geometry and reinforcement distribution. The results were then analyzed to relate the wall geometry and reinforcement distribution and the performance of BTB walls. Optimum reinforcement pattern was also investigated.

Effect of vertical reinforcement connection level on seismic behavior of precast RC shear walls: Experimental study

  • Yun-Lin Liu;Sushil Kumar;Dong-Hua Wang;Dong Guo
    • Earthquakes and Structures
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    • v.26 no.6
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    • pp.449-461
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    • 2024
  • The vertical reinforcement connection between the precast reinforced concrete shear wall and the cast-in-place reinforced concrete member is vital to the performance of shear walls under seismic loading. This paper investigated the structural behavior of three precast reinforced concrete shear walls, with different levels of connection (i.e., full connection, partial connection, and no connection), subjected to quasi-static lateral loading. The specimens were subjected to a constant vertical load, resulting in an axial load ratio of 0.4. The crack pattern, failure modes, load-displacement relationships, ductility, and energy dissipation characteristics are presented and discussed. The resultant seismic performances of the three tested specimens were compared in terms of skeleton curve, load-bearing capacity, stiffness, ductility, energy dissipation capacity, and viscous damping. The seismic performance of the partially connected shear wall was found to be comparable to that of the fully connected shear wall, exhibiting 1.7% and 3.5% higher yield and peak load capacities, 9.2% higher deformability, and similar variation in stiffness, energy dissipation capacity and viscous damping at increasing load levels. In comparison, the seismic performance of the non-connected shear wall was inferior, exhibiting 12.8% and 16.4% lower loads at the yield and peak load stages, 3.6% lower deformability, and significantly lower energy dissipation capacity at lower displacement and lower viscous damping.

Evaluation of behavior of updated three-dimensional panel under lateral load in both independent and dependent modes

  • Rezaifar, Omid;Nik, Hamun Adeli;Ghohaki, Majid
    • Earthquakes and Structures
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    • v.14 no.1
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    • pp.11-20
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    • 2018
  • Three-dimensional panels are one of the modern construction systems which can be placed in the category of industrial buildings. There have always been a lot of studies and efforts to identify the behavior of these panels and improve their capacity due to their earthquake resistance and high speed of performance. This study will provide a comparative evaluation of behavior of updated three-dimensional panel's structural components under lateral load in both independent and dependent modes. In fact, this study tries to simultaneously evaluate strengthening effect of three-dimensional panels and the effects of system state (independent, L-shaped and BOX shaped Walls) with reinforcement armatures with different angles on the three-dimensional panels. Overall, six independent wall model, L-shaped, roofed L-shaped, BOX-shaped walls with symmetric loading, BOX -shaped wall with asymmetrical loading and roofed BOX-shaped wall were built. Then the models are strengthened without strengthened reinforcement and with strengthened reinforcements with an angle of 30, 45 and 60 degrees. The applied lateral loading, is exerted by changing the location on the end wall. In BOX-shaped wall, in symmetric and asymmetric loading, the load bearing capacity will be increased about 200 and 50% respectively. Now, if strengthened, the load bearing capacity in symmetric and asymmetric loading will be increased 3.5 and 2 times respectively. The effective angle of placement of strengthened reinforcement in the independent wall is 45 and 60 degrees. But in BOX-shaped and L-shaped walls, the use of strengthened reinforcement 45 degrees is recommended.

A case study on reinforcement and design application of reinforced earth wall using micro pile (마이크로 파일을 이용한 블록식 보강토옹벽의 보강 및 설계적용 사례 연구)

  • Hong, Kikwon;Han, Jung-Geun;Lee, Kwang-Wu;Park, Jong-Beom
    • Journal of the Korean Geosynthetics Society
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    • v.13 no.4
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    • pp.161-167
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    • 2014
  • This paper describes reinforcement method of reinforced earth wall near the abutment. The excessive displacement of a case affected by reduction of bearing capacity due to macro-environment condition like a coast. That is, the front displacement of reinforced earth wall has been happening continuously due to strength reduction of foundation ground. The micro pile is applied to reinforcement method, in order to secure a bearing capacity and global slope stability of reinforced earth wall. The results of numerical analysis confirmed that reinforcement method based on micro pile can secure a stability of structure, while the reconstruction of reinforced earth wall is impossible by construction and macro-environment condition.