• Title/Summary/Keyword: retaining wall methods

Search Result 134, Processing Time 0.022 seconds

Case Study on the Countermeasure Methods and Collapsed Sources of Segmental Retaining Wall Considering Site Conditions (시공환경을 고려한 블록식 보강토옹벽의 붕괴요인 분석 및 대책방안 사례연구)

  • Han, Jung-Geun;Cho, Sam-Deok;Jeong, Sang-Seom;Lee, Kwang-Wo;Kim, Ji-Sun
    • Journal of the Korean Geosynthetics Society
    • /
    • v.4 no.3
    • /
    • pp.35-43
    • /
    • 2005
  • The geosynthetic reinforced segmental retaining walls(SRW) are improved that the disadvantage of existed retaining wall and the workability in field. Recently, the segmental retaining wall is replacing the exited wall because it is quickly advanced to using by the block in-situ. The use, therefore, is increasing. But, the trends of the large scaled construction was developed that the problems likely to crack and collapse, those are caused of careless in design and construction of SRW not considering about various surrounding conditions. In this study, the cause analysis on destructed SRW was carried out that based on the datum of measured displacement of walls, rainfall features and ground sounding conditions. Also, the analysis of the global slope stability was carried out on collapsed section and non-collapsed section using critical equilibrium method. For the rational stability and analysis of slope including SRW structure, the site conditions including situations of topography, ground and histories of construction and collapse etc should be considered. The rational countermeasure methods for non-collapsed and collapsed areas may be sustained as much as possible current state.

  • PDF

A Case Study on Collapsed Geosynthetic Reinforced Segmental Retaining Wall (블록식 보강토옹벽의 붕괴사례 연구)

  • Kim, Byoung-Il;Yoo, Wan-Kyu;Kim, Kyeong-Mo;Lee, Bong-Yeol
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.4
    • /
    • pp.2006-2012
    • /
    • 2013
  • This case study deal with the investigation of various causes and analyses concerning the cases of the collapse of reinforced segmental retaining walls installed for newly constructing a peripheral road within the campus of ${\bigcirc}{\bigcirc}$ University located in Gyeonggi-do. As results of stability analyses and reviewing of design documents concerning collapsed reinforced segmental retaining walls, such a collapse appeared because of problems related to construction including poor-compacted backfill, the omission of the investigation on the bearing capacity, the length and space in the installation of reinforced materials, and drainage systems. Also, problems during diverse types of designing were confirmed involving the stability analysis of the entire slope stability to be considered during designing and failure in application of the proposed methods of FHWA or NCMA which are generally used for two-tier reinforced segmental retaining walls. In addition, based on these details of the stability assessment, the study proposed reinforcement solutions and construction methods for stabilizing reinforced segmental retaining walls to be reconstructed in the future.

Characteristics of Collapsed Retaining Walls Using Elasto-plastic Method and Finite Element Method (탄소성 방법과 유한요소법에 의한 붕괴 토류벽의 거동차이 분석)

  • Jeong, Sang-Seom;Kim, Young-Ho
    • Journal of the Korean Geotechnical Society
    • /
    • v.25 no.4
    • /
    • pp.19-29
    • /
    • 2009
  • In this study, a numerical analysis was performed to predict the sequential behavior of anchored retaining wall where the failure accident took place, and verified accuracy of prediction through the comparisons between prediction and field measurement. The emphasis was given to the wall behaviors and the variation of sliding surface based on the two different methods of elasto-plastic and finite element (shear strength reduction technique). Through the comparison study, it is shown that the bending moment and the soil pressure at construction stages produce quite similar results in both the elasto-plastic and finite element method. However, predicted wall deflections using elasto-plastic method show underestimate results compared with measured deflections. This demonstrates that the elasto-plastic method does not clearly consider the influence of soil-wall-reinforcement interaction, so that the tension force (anchor force and earth pressure) on the wall is overestimated. Based on the results obtained, it is found that finite element method using shear strength reduction method can be effectively used to perform the back calculation analysis in the anchored retaining wall, whereas elasto-plastic method can be applicable to the preliminary design of retaining wall with suitable safety factor.

The Analysis of Lateral Movement at the Top of Retaining Wall in the Downtown Area (도심지 옹벽 상단에서의 수평변위에 관한 사례분석)

  • Bae, Yoon-Shin
    • Journal of the Korean GEO-environmental Society
    • /
    • v.10 no.3
    • /
    • pp.63-71
    • /
    • 2009
  • The movement of in-situ walls has become very important as construction in large cities moves upward, instead of outward. Tall structures typically have deep excavations not on1y to provide extra space for parking, but also to reduce the potential settlement of the building. These large excavations require a robust bracing system to resist the lateral earth pressures as the depth increases. Methods to predict deflections of the retaining systems are of utmost importance because wall movements allow potentia1 settlement of adjacent structures. Case studies will be analyzed and measured waI1 def1ections will be compared with predictions from empirica1ly derived charts.

  • PDF

Assessment of Displacement and Axial Force of Earth Retaining Wall at Each Excavation Step Using Direct Algorithm Back Analysis (직접알고리즘 역해석 기법을 이용한 굴착단계별 흙막이 가시설 변위 및 축력의 적정성 평가)

  • So-Ra Kang;Je-Seok Jeon;Yeong-Jin Lee;Jun-Seok Lee;Kang-Il Lee
    • Journal of the Korean Geosynthetics Society
    • /
    • v.23 no.1
    • /
    • pp.27-37
    • /
    • 2024
  • In this study, direct algorithm-based back analysis was utilized to perform back analysis on two actual earth retaining wall fields, which was then compared with genetic algorithm-based method to evaluate the suitability of the back analysis. Additionally, in order to propose effective utilization methods of the program, the measurement data, as the input for the back analysis, was varied for each excavation step, and the applicability of the back analysis results(displacement, axial force) was examined. The research findings indicate that both direct algorithm and genetic algorithm show high applicability; however, the optimization for this program is better predicted by the direct algorithm. Moreover, in order to effectively use the back analysis program employing the direct algorithm, it was evaluated that relatively accurate prediction of the earth retaining wall behavior could be achieved by inputting measurement data from the 7th excavation step for fields with final excavation steps ranging from 8 to 11.

Improved Effects of Reinforced Wall with Types of Connection Methods (보강재 연결 유.무에 따른 보강토옹벽의 보강효과)

  • 신은철;최찬용
    • Geotechnical Engineering
    • /
    • v.14 no.5
    • /
    • pp.67-76
    • /
    • 1998
  • The commonly used method to secure the stability of reinforced retaining structure is the reinfocement of backfill with connection attached or unattached to the geogrid type wall. Laboratory model tests for both cartes were conducted to investigate the effectiveness of geogridreinforcement, length of reinforcement inclusion, failure envelop, and the relationships between the face wall displacement and vertical settlement. The bearing capacity of each case was also determined. According to the model test results, geogrid-reinforced rigid wall is very effective for increasing the bearing capacity and reducing the displacement of retaining wall. The observed sliding line of model test is similar to the theoretical one.

  • PDF

Analysis of the Impact on Prediction Models Based on Data Scaling and Data Splitting Methods - For Retaining Walls with Ground Anchors Installed (데이터 스케일링과 분할 방식에 따른 예측모델의 영향 분석 - 그라운드 앵커가 설치된 흙막이 벽체 대상)

  • Jun Woo Shin;Heui Soo Han
    • The Journal of Engineering Geology
    • /
    • v.33 no.4
    • /
    • pp.639-655
    • /
    • 2023
  • Recently, there has been a growing demand for underground space, leading to the utilization of earth retaining walls for deep excavations. Earth retaining walls are structures that are susceptible to displacement, and their measurement and management are carried out in accordance with the standards established by the Ministry of Land, Infrastructure, and Transport. However, managing displacement through measurement can be considered similar to post-processing. Therefore, in this study, we not only predicted the horizontal displacement of a retaining wall with ground anchors installed using machine learning, but also analyzed the impact of the prediction model based on data scaling and data splitting methods while learning measurement data using machine learning. Custom splitting was the most suitable method for learning and outputting measurement data. Data scaling demonstrated excellent performance, with an error within 1 and an R-squared value of 0.77 when the anchor tensile force and water pressure were standardized. Additionally, it predicted a negative displacement compared to a model that without scaling.

An Analytical Study on Determination of Dimensions of Drystone Masonry Retaining Walls (석축의 단면결정에 대한 해석적 연구)

  • Seung-Hyun Lee
    • Journal of the Society of Disaster Information
    • /
    • v.19 no.1
    • /
    • pp.60-68
    • /
    • 2023
  • Purpose: In order to find out stability condition which governs design of drystone masonry retaining walls and changing patterns of installed width of blocks of the wall for each stability conditions, typical wall was assumed and designed. Method: For the purpose of this study, 10 m high drystone masonry retaining wall with general block size and soil properties were considered and dimensions of the wall were determined by applying stability conditions of sliding and overturning and the design results were compared with each other. Result: According to the design results, installed width of blocks determined by considering stability of sliding were greatly less than those determined by considering stability of overturning and these differences were not decreased noticeably even though same values of factors of safety for sliding and overturning were applied. Between the two methods of determining the installed width of blocks, it could be seen that the method of considering failure wedge of lower part of overturning parts of the wall governed the design instead of considering horizontal base of overturning parts of the wall. Conclusion: In case of considering failure wedge of lower part of overturning parts of the wall, it could be seen that the installed width of blocks increased as the inclination angle of failure wedge increased. In case of considering overturning at the lower part of the wall with certain assumed inclination angle of failure wedge, it could be seen that installed width of blocks decreased as the inclination angle of failure wedge decreased by geometric restrictions of the wall.

The Case Study of Design on Steel Pipe Sheet Pile for Earth Retaining Wall on Deep Excavation (대심도 지반굴착을 위한 벽강관말뚝 흙막이공법의 설계 사례 연구)

  • Byung-Il Kim;Jong-Ku Lee;Kyoung-Tae Kim;Kang-Han Hong;Sang-Jae Han
    • Journal of the Korean Geosynthetics Society
    • /
    • v.22 no.1
    • /
    • pp.53-66
    • /
    • 2023
  • In this study, the results of the elasto-plastic beam analysis, finite element analysis and optimization design of the steel pipe sheet pile applied as an earth retaining wall under the deep excavation were presented. Through this study, it was found that the high-strength and sea resistant steel pipe has high allowable stress, excellent structural properties, favorable corrosion, and high utilization as an earth retaining wall, and the C-Y type joint has significantly improved the tensile strength and stiffness compared to the traditional P-P type. In addition, it was investigated that even if the leak or defect of the wall occurs during construction, it has the advantage of being able to be repaired reliably through welding and overlapping. In the case of steel pipe wall, they were evaluated as the best in views of the deep excavation due to the large allowable bending stress and deformation flexibility for the same horizontal displacement than CIP or slurry wall. Elasto-plastic and finite element analysis were conducted in consideration of ground excavation under large-scale earth pressure (uneven pressure), and the results were compared with each other. Quantitative maximum value were found to be similar between the two methods for each item, such as excavation behavior, wall displacement, or member force, and both analysis method were found to be applicable in design for steel pipe sheet pile wall. Finally, it was found that economical design was possible when determining the thinnest filling method with concrete rather than the thickest hollow shape in the same diameter, and the depth (the embedded length through normality evaluation) without rapidly change in displacement and member force.