• Title/Summary/Keyword: retaining wall

Search Result 733, Processing Time 0.032 seconds

Measured Behavior of Full-Scale Soil-Reinforced Segmental Retaining Wall (계단식 형태의 블록식 보강토 옹벽의 거동특성)

  • Yoo, Chung-Sik;Jung, Hyuk-Sang
    • Journal of the Korean Geosynthetics Society
    • /
    • v.2 no.1
    • /
    • pp.15-25
    • /
    • 2003
  • This paper presents the results of instrumentation of a two-level of soil-reinforced segmental retaining wall. Instrumentation items include the lateral wall displacements and the geogrid strains at several locations. The instrumentation is still long carried in order to examine long-term behavior. The result indicate that the upper wall has a significant effect on the behavior of the lower wall doubling the wall moved. The wall also exhibits significant post-construction movements that had ceased several months after the wall completed. The implication of the findings from this study was discussed in great detail.

  • PDF

Landscape Design for Renovation of the Second Namsan Tunnel (남산2호터널 조형물 설계)

  • 김신원
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.30 no.2
    • /
    • pp.63-69
    • /
    • 2002
  • The Second Namsan Tunnel required renovation. The landscape design was conducted as part of the comprehensive programs for renovation. The landscape design covered site analysis, design development, a working drawing and a maintenance plan. In May of 2001, the Second Namsan Tunnel was renovated and reopened to traffic. The tunnel was recreated as a new type of tunnel with function and beauty. The entrance and retaining wall of the tunnel has public character. Users are greatly affected by the entrance and retaining walls along roads. The landscape architect had to find new materials and methods to improve the environment and to combine artwork with the entrance and walls of the tunnel. The surface of the tunnel entrance and retaining walls are artistically treated with ceramic tiles and paint. Various regional characteristics and cultural meaning are symbolically expressed. Or the tunnel entrance from the Joong-gu side, entitled "Glory of the Future", the hibiscus symbolizes the bright and glorious future of Korea. On the retaining walls, entitled "Hope", the promising Joong-gu is symbolized through image of Korean magpies, mountains, rocks, roses, winds and nature. As for the tunnel entrance from the Yongsan-gu side, entitled "Vivid Spirit", pine trees symbolize the Koreans′strong will and an enterprising spirit. On the retaining walls, entitled "Lively Motions", Yongsan-gu is symbolized through image of pigeons, mountains, rocks, roses, winds and clear skys. The entrance and retaining wall of the Second Namsan Tunnel, whose surfaces are treated with tiles and paint with artistic value, would create an atmosphere using large-scale wall paintings. In this artwork, users would perceive a unique sense of place through the symbolic images of the vertical planes of the tunnel.

Case Studies on Ground Improvement by High Pressure Jet Grouting(II) Effect on the Ground Reinforcement and Cut off of Ground Water Behind Temporary Retaining Walls (고압분사주입공법에 의한 지반개량사례연구(II) -흙막이벽 배면지반보강 및 차수효과)

  • Yun, Jung-Man;Hong, Won-Pyo;Jeong, Hyeong-Yong
    • Geotechnical Engineering
    • /
    • v.12 no.5
    • /
    • pp.5-16
    • /
    • 1996
  • When braced excavation with temporary retaining wall installation, is performed in loose sand with high ground water level boiling may be induced and considerable damage on the excavation works and structures in the vicinity can take place. Recently, for the purpose of reinforcement of ground and cut-off of ground water behind the temporary retaining wall, high pressure jet grouting is widely used. The purpose of this paper is to investigate the effects of jet grouting on ground reinforcement and cut -off of the ground water behind temporary retaining walls for braced excavation. A series of both laboratory and field tests has been performed. The test results show that high pressure jet grouting has sufficient effects on reinforcement of stiffness of ground and retaining wall. The permeability of the improved ground was 10-f_ 10-3cm l s smaller than those of the original ground. Therefore, the effect on cut off of ground water behind temporary retaining walls could be improved by high pressure jet grouting method.

  • PDF

Investment Prioritization Method for Steep Slope Retaining Wall Considering the Disaster Risk and the Repair and Reinforcement Cost (재해위험도와 보수보강비용을 고려한 급경사지 옹벽의 투자 우선순위 결정방법 연구)

  • Choi, Jae-Soon;Shin, Yean-Ju;Baek, Woo-Hyun
    • Journal of the Korean Geotechnical Society
    • /
    • v.38 no.12
    • /
    • pp.79-89
    • /
    • 2022
  • Every summer in our country, an accident occurs, in which the retaining wall on a steep slope collapses due to torrential rain. According to the data on the results of steep slope risk assessment in 2019, over 780 retaining walls are below grade C; therefore, preparing for countermeasures is urgent. However, due to the limited budget for the repair and reinforcement of these retaining walls, it is necessary to discuss the investment prioritization. In this study, a prioritization method was proposed at the network and project levels along with the review of the revised criteria of disaster risk assessment in the steep slope retaining wall, and an application research in the network level was conducted for six retaining walls. Moreover, it is proposed that the priority index was determined by using the actual cost for repair and reinforcement in determination of the project level prioritization.

Concrete-Panel Retaining Wall anti-crack sleeve inserted (균열방지 슬리브가 매설된 패널식 옹벽)

  • Jang, Sung-Ho;Chung, Jee-Seung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.5 no.3
    • /
    • pp.345-349
    • /
    • 2019
  • In Korea, the mountainous area occupies more than 70% of the whole country, cutting of earth slope that cuts a part of the ground surface is widely used when building infrastructures such as road, railroad, and industrial complex construction. In recent years, regulations on environmental damage have become more strict, and various methods have been developed and applied. Among them, Concrete-Panel Retaining Wall technique is actively applied. Concrete-Panel Retaining Wall is a method to resist horizontal earth pressure by forming a wall by attaching a precast retaining wall to the front of the support material and increasing the shear strength of the disk through reinforcement of the support material. Soil nailing, earth bolt, and ground anchor are used as support material. Among them, ground anchor is a more aggressive reinforcement type that introduces tensile load in advance to the steel wire, and a large concentrated load acts on the front panel. This concentrated load is a factor that creates cracks in the concrete panel and reduces the durability of the retaining wall itself. In this study, steel pipe sleeves and reinforcements were purchased at the anchorage of the panel to prevent cracks, and by applying bumpy shear keys to the end of the panel, the weakness of the individual behavior of the existing grout anchors was improved. The problem of degraded landscape by exposure to front concrete of retaining wall and protrusion of anchorage was solved by the production of natural stone patterns and the construction of sections that do not protrude the anchorage. In order to verify the effectiveness of anti-crack sleeves and reinforcements used in the null, indoor testing and three-dimensional numerical analysis have been performed, and the use of steel pipe sleeves and reinforcements has demonstrated the overall strength increase and crack suppression effect of panels.

Evaluation of PBD as Horizontal Drains of Soilbag Retaining Wall (토낭 보강토 옹벽의 수평 배수재로서 PBD의 적용성 평가)

  • Shin, Eun-Chul;Lee, Myung-Shin;Kim, Sung-Hwan
    • Journal of the Korean Geosynthetics Society
    • /
    • v.12 no.2
    • /
    • pp.35-42
    • /
    • 2013
  • Recently, construction of reinforced earth structure using geosynthetics has been increased because it has advantages such as construction efficient, cost effectiveness and appearance aspect against existing gravity or cantilever retaining wall. However due to the climate change in Korea excessive inflow of ground water and surface water from heavy rainfall could affect the stability of reinforced retaining wall seriously. So the discharge capacity of drains should be evaluated by using experimental method in the design of reinforced earth wall. In this study, instead of concrete block used in most of the retaining wall, eco-friendly porous soilbag was used. This paper describes the test method and result of the laboratory testing for determination of discharge capacity utilizing PBDs.

Effects of Functional Improvement of Multiaxis Flat Continuous Soil Cement Earth Retaining Wall (다축 평면 연속형 SCW 흙막이 벽체의 개선 효과)

  • Chung, Choong-Sub;Yoo, Chan Ho;Nam, Ho Seong;Choi, In Gyu;Baek, Seung Cheol
    • Journal of the Korean Geotechnical Society
    • /
    • v.39 no.11
    • /
    • pp.7-22
    • /
    • 2023
  • In January 2022, a new legislation was enforced to enhance the safety of underground construction. Consequently, a comprehensive assessment of underground safety is now an integral part of the planning process, including an evaluation of its impact. Ensuring the stability of temporary retaining walls during underground excavation has become paramount, prompting a heightened focus on the assessment of underground safety. This study delves into the analysis of the Multi-axis Flat Continuous Soil Cement Wall retaining wall (MFS) construction method. This method facilitates the expansion of wall thickness in the ground and provides flexibility in selecting and spacing H-piles. Through laboratory model tests, we scrutinized the load-displacement behavior of the wall, varying the H-pile installation intervals using the MFS method. Additionally, a 3-dimensional numerical analysis was conducted to explore the influence of H-pile installation intervals and sizes on the load for different thicknesses of the MFS retaining wall. The displacement analysis yielded the calculation of the height of the arching effect acting on the wall. To further our understanding, a design method was introduced, quantitatively analyzing the results of axial force and shear force acting on the wall. This involved applying the maximum arching height, calculated by the MFS method, to the existing member force review method. The axial force and shear force, contingent on the H-pile installation interval and size applied to the MFS retaining wall, demonstrated a reduction effect ranging from 24.6% to 62.9%.

An Experimental Study on the Stability of Assembled Earth Retaining Wall in Sandy Ground (사질토 지반에 설치된 조립식 지주옹벽(AER)의 안정성에 관한 실험적 연구)

  • Yoo, Jae-Won;Im, Jong-Chul;Hwang, Sung-Pil;Kim, Chang-Young;Choi, Jung-Hyun;Kim, Hong-Sun
    • Journal of the Korean Geotechnical Society
    • /
    • v.32 no.2
    • /
    • pp.43-52
    • /
    • 2016
  • Assembled Earth Retaining wall (AER-wall is used here) using back pile (back supporting beam is used from here) has been developed at Pusan National University. Both cost and time have been significantly reduced because AER-wall can be fabricated in a shop. Also its stability has been improved with a back supporting beam reducing earth pressure. In this study, the test results were analyzed after laboratory model tests were performed. The lateral displacement of AER-wall significantly decreased with both inclined wall and back supporting beams. As a result, the stability of AER-wall and effect of back supporting beam have been analyzed and verified.

Design of the Green Wall System considering Distribution Effect of Earth Pressure by Soil Nail (네일의 토압분담 효과를 고려한 Green Wall 시스템의 설계)

  • Park, Si-Sam;Cho, Sung-Han;Yoo, Chan-Ho;Kim, Hong-Taek;Kim, Yong-Yeon
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.03a
    • /
    • pp.1038-1045
    • /
    • 2006
  • The Green Wall is highest eco-system among a segmental retaining wall systems. Recently, the demand of high segmental retaining wall (SRW) is increased in domestic. The soil nailing system is applied in order to maintain the high SRW stability for steeper slope. However, the proper design approach that can consider the earth pressure reduction effects in soil nailing system has not been proposed. This study was performed to introduce the design case by 'Two-Body Translation mechanism' to be able to consider distribution of earth pressure in the soil nailing when designing the green wall using soil nailing system. Also, this study attempts to evaluate the earth pressure change when advanced soil nailing system is constructed using $FLAC^{2D}$ ver. 3.30 program and 'Two-Body Translation mechanism'. Also in this study, various parametric studies using numerical methods as shear strength reduction (SSR) technique and limit equilibrium technique were carried out. In the parametric study, the length ratio and the bond ratio of the soil nailing were changed to identify the earth pressure reduction effect of the retaining wall reinforced by soil nailing.

  • PDF

Computer modeling of crack propagation in concrete retaining walls: A case study

  • Azarafza, Mehdi;Feizi-Derakhshi, Mohammad-Reza;Azarafza, Mohammad
    • Computers and Concrete
    • /
    • v.19 no.5
    • /
    • pp.509-514
    • /
    • 2017
  • Concrete retaining walls are the most common types of geotechnical structures for controlling instable slopes resulting from lateral pressure. In analytical stability, calculation of the concrete retaining walls is regarded as a rigid mass when its safety is required. When cracks in these structures are created, the stability may be enforced and causes to defeat. Therefore, identification, creation and propagation of cracks are among the important steps in control of lacks and stabilization. Using the numerical methods for simulation of crack propagation in concrete retaining walls bodies are among the new aspects of geotechnical analysis. Among the considered analytical methods in geotechnical appraisal, the boundary element method (BEM) for simulation of crack propagation in concrete retaining walls is very convenient. Considered concrete retaining wall of this paper is Pars Power Plant structured in south side in Assalouyeh, SW of Iran. This wall's type is RW6 with 11 m height and 440 m length and endurance of refinery construction lateral forces. To evaluate displacement and stress distributions (${\sigma}_{1,max}/{\sigma}_{3,min}$), the surrounding, especially in tip and its opening crack BEM, is considered an appropriate method. By considering the result of this study, with accurate simulation of crack propagation, it is possible to determine the final status of progressive failure in concrete retaining walls and anticipate the suitable stabilization method.