• Title/Summary/Keyword: Reinforcement, Settlement

Search Result 241, Processing Time 0.019 seconds

Model Tests for the Effect of Settlement Restraint of Adjacent Structure During Tunnel Excavation (터널굴착에 따른 인접 구조물 침하 억제효과에 관한 실내모형실험)

  • 유문오;임종철;고호성;박이근
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.03b
    • /
    • pp.141-148
    • /
    • 2000
  • In this study, differential settlements of adjacent structure and behaviour of ground during tunnel excavation and the effect of micropile installed to preserve differential settlement of structure are measured and analyzed by model test. In the test results, the effective range of reinforcement is suggested.

  • PDF

Behavior of Reinforced Earth Retaining Wall for Permitting Reinforcement to Subside with Monitoring (현장계측을 통한 보강재 침하형 보강토 옹벽의 거동특성)

  • Chung, Jin-Hyuck;Oh, Jong-Keun;Lee, Song
    • Journal of the Korean Geotechnical Society
    • /
    • v.25 no.2
    • /
    • pp.5-15
    • /
    • 2009
  • The conventional reinforced earth retaining wall has the connector system to fix the reinforcement and block. However, this system defect may cause the crack of block and the rupture of reinforcement due to the stress concentration near the face of reinforced earth retaining wall. Hence, the new connector system which was able to allow the settlement of reinforcement was developed in this study and a test was carried out in the study area which is divided into the conventional reinforced earth retaining wall and reinforced Earth Retaining Wall driving the settlement. As the results of field monitoring in situ, the ratio of tensile force calculated at maximum value on contiguous portion of front block showed that the settlement type decreased the stress concentration near the face of front block greater than the conventional type.

Reinforcement and Arching Effect of Geogrid-reinforced and Pile-supported Embankments (지오그리드와 말뚝으로 보강된 성토지반의 보강 및 아칭효과 연구)

  • Oh Young-In;Shin Eun-Chul
    • Journal of the Korean Geotechnical Society
    • /
    • v.21 no.10
    • /
    • pp.5-16
    • /
    • 2005
  • Geosynthetic-reinforced and pile-supported embankments have been increasingly used and researched around the world. The inclusion of one or multiple geosynthetic reinforcements over the pile is intended to enhance the efficiency of load transfer from soft ground to piles, to reduce total and differential settlement and increase global or local stability. In this paper, the reinforcement effectiveness and arching effect of the geogrid-reinforced and pile-supported embankments have been studied in terms of field model tests and numerical analysis with varying the space between piles and reinforcement. 2-dimensional numerical analysis has been conducted using the FLAC (Fast Lagrangian Analysis of Continua) program. And load transfer mechanisms between soil-piles-geogrid were investigated. The mechanisms of load transfer can be considered as a combination of embankment soil arching, tension geogrid, and stress concentration due to the stiffness difference between pile and soft ground. Based on the field model test and numerical analysis results, it was found that the geosynthetic reinforcement slightly interferes with soil arching, and helps reduce differential settlement of the soft ground. Also. at the D/b=3 (D: spacing of pile cap, b: diameter of pile), the total settlement is reduced by about $40\%$ compared to that without reinforcement. For $D/b{\ge}6$, the effectiveness of geogrid reinforcement in reducing settlement is negligible.

Characteristics of Settlement and Scour of Square-Shaped Hybrid Reef according to Placement Types (배치 형태에 따른 사각형 복합 인공어초의 침하 및 세굴 특성)

  • Yun, Daeho;Kim, Yuntae
    • Journal of the Korean Geosynthetics Society
    • /
    • v.16 no.2
    • /
    • pp.1-10
    • /
    • 2017
  • This study carried out several laboratory tests such as water tank settlement test and two-dimensional water flow test to investigate settlement and scour characteristics of a square-shaped hybrid reef which was reinforced with geogrid. In addition, numerical analysis was also performed to find out scour characteristics of the square-shaped hybrid reef with different placement types (type A; straight placement type, type B; zigzag placement type). Laboratory test results indicated that settlement and scouring depth significantly reduced in hybrid reefs reinforced with geogrid, compared with those without reinforcement. Two-dimentional water flow tests and numerical test results also showed that scouring depth and flow velocity of placement type A more decreased than those of type B.

A study on rail roadbed reinforcement by geogrids (지오그리드를 활용한 철도 노반 강화에 대한 연구)

  • 신은철;신민호;김두환;신동훈
    • Proceedings of the KSR Conference
    • /
    • 1998.11a
    • /
    • pp.96-102
    • /
    • 1998
  • The characteristics of roadbed are very important factors in the design of railways. Laboratory model tests were performed to investigate the effectiveness of geogrid placement in the subbase layers on reinforcement. Design parameters of reinforcement were determined through the laboratory model tests. The results indicated that geogrid reinforcement is increased the bearing capacity and reduced the settlement of railway foundation. The optimum length of geogrid reinforcement is about 4B. The effective depth of geogrid placement from the bottom of ballast is about 0.1B-0.2B depended on magnitude of applied load.

  • PDF

The practitioners' perceptions on settlement of cultural welfare policy (문화복지 제도정착에 관한 실천가 인식)

  • Choi, Jong Hyug;Yu, Young Ju
    • Korean Journal of Social Welfare Studies
    • /
    • v.43 no.2
    • /
    • pp.179-206
    • /
    • 2012
  • This study was based on politic reality which is being developed within the ambiguity of cultural welfare, and discussed what sort of awareness the practitioners show in the settlement process of the cultural welfare policy in depth. 4 elements were discovered in the settlement process of the cultural welfare policy which the practitioners are aware of. The elements are value(pursuit of comprehensive mankind), element of practice(process of operation), elements of external influences(process of policy settlement), and elements of internal influences(reinforcement of practitioners capability). This means that not only the process of policy settlement in a narrow sense, but also value, practice, and reinforcement of practitioners' capability for the provision of better service should be considered for the settlement of the policy. This study which analyzed the cultural welfare practitioners' awareness of policy settlement process is significant in that it provides the basic data for future settlement of the cultural welfare policy.

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.

Response of rigid footing on reinforced granular fill over soft soil

  • Ramu, K.;Madhav, Madhira R.
    • Geomechanics and Engineering
    • /
    • v.2 no.4
    • /
    • pp.281-302
    • /
    • 2010
  • An extended model for the response of a rigid footing on a reinforced foundation bed on super soft soil is proposed by incorporating the rough membrane element into the granular bed. The super soft soil, the granular bed and the reinforcement are modeled as non-linear Winkler springs, non-linear Pasternak layer and rough membrane respectively. The hyperbolic stress-displacement response of the super soft soil and the hyperbolic shear stress-shear strain response of the granular fill are considered. The finite deformation theory is used since large settlements are expected to develop due to deformation of the super-soft soil. Parametric studies quantify the effect of each parameter on the stress-settlement response of the reinforced foundation bed, the settlement and tension profiles.

Application of D-ROG technology for restoration of the subsided building (침하건물 복원을 위한 정밀 다점 주입공법의 적용)

  • Lee, Ju-Hyung;Koh, Hyo-Seog;Hong, Jin-Pyo;Park, Jae-Hyun;Cho, Sam-Deok
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.03a
    • /
    • pp.405-410
    • /
    • 2009
  • This paper presents a case study that achieved both of serviceability and safety of the building through soil reinforcement and restoration around foundations subjected to serious differential settlement using D-ROG method. The building which has one basement floor and three ground floors is founded on soft ground and differential settlement occurred to the maximum extent of 678mm. The foundation type of the building is a independent mat foundation. Soil profiles consist of landfill layer, alluvial layer, weathered rock, and soft rock. The bearing layer consisting of gravel and weathered rock is located 16.0~17.0m below the bottom of the building. As a result of soil reinforcement and restoration, the recovery ratio of more than 90% can be attained with the maximum set-up of 657mm.

  • PDF