• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.218-223
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• 2009

During the process of excavation for substructures of buildings, precise and constant measurements of retaining wall displacement is crucial for construction to be complete and safe. Currently an inclinometer is used to measure displacement around the perimeter of an excavation site. The existing inclinometer system requires an instrument to be placed inside pre-bored holes for each measurement with an typical interval of two weeks. This makes it difficult to obtain continuous displacement data, especially during a critical time such as rainy season in summer. Also, the existing inclinometer is placed at certain distance away from the retaining wall system itself. Thus, exact measurement of retaining wall movement is compromised because of the distance between the retaining wall and the inclinometer. This paper presents the development of wireless inclinometer system for the displacement measurement of retaining walls by being attached directly to the retaining wall. The result of the application of the developed systems are provided with advanced ubiquitous sensor network (USN) system features. The USN technique incorporated into the system enables users to monitor movement data from wherever possible and convenient such as construction manager's office on site or any other places connected through internet. The research work presented in this paper will provide a basis to save construction time and cost by preventing safe-related unexpected delay of construction due to the failure or collapse of retaining walls.

• 기술발표회
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• 통권2006호
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• pp.162-171
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• 2006

Segmental Grid Retaining Wall is one of the segmental grid retaining walls using headers and stretchers to establish the framework of the wall In this method, grids formed by the intersection of headers and stretchers are generally filled with the gravel to maintain the weight of the wall Therefore, the construction can be carried out with higher speed and much economically when compared with the concrete retaining wall Furthermore, it has high drain capacity, and environmentally friendly aspects also have been pointed out because the possibility of the planting at the front of the wall However, in the segmental grid retaining wall method, the relative movement between the individual headers and stretchers was generally recognized, and stress redistribution in the gravel filling was also observed when subjected to the external loading and self-weight of filling Therefore, it has been thought that the distribution of the earth pressure in the segmental grid retaining wall system differ from that of the concrete retaining wall In this study, the surcharge tests using the scaled model segmental grid retaining wall was carried out to observe the distribution of the earth pressure in the segmental grid retaining wall The earth pressure was measured in the six specified height of wall, and the distribution of the pressure was analyzed. Furthermore, the earth pressure by computation or by the test using the concrete retaining wall was also considered to make comparison

• 한국터널지하공간학회 논문집
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• 제17권3호
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• pp.267-281
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• 2015

본 연구에서는 흙막이벽과 같은 수직굴착과 터널과 같은 지하공간의 연속적인 굴착에 따른 지반 거동과 토압 변화를 실험적으로 연구하였다. 굴착 단계별로 벽체 거동, 토압 변화, 그리고 지표 침하의 측정이 가능한 길이 160cm, 높이 120cm의 모형 토조를 제작하였다. 실험은 균일하게 조성된 사질토 지반에서 벽체에 임의의 변위를 가하고, 토압 변화와 지표 침하를 확인하는 방식으로 수행하였다. 모형실험은 흙막이벽과 지하공간의 연속적인 시공을 모사하기 위하여 흙막이벽 굴착을 모사하는 우측벽체 10개 및 지하공간 굴착을 모사하는 하부벽체 5개를 순서대로 거동시켜 모사하였다. 실험 결과, 벽체의 주동변위로 감소된 토압이 주변 벽체로 분담되는 아칭현상이 모든 벽체에서 발생함을 확인하였다. 연속되는 시공을 모사한 실험에서 phase마다 아칭현상을 확인할 수 있으나, 하부1단 벽체의 거동 시, 우측10단 벽체는 다른 경우와 달리 토압이 50%정도만 회복됨을 보였다.

• 한국농촌건축학회논문집
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• 제2권2호
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• pp.115-126
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• 2000

Retaining walls are used to prevent excessive movement of retained soils. Typical retaining walls include gravity, reinforced concrete, reinforced earth and tie-back. However, from a practical viewpoint there are still drawbacks among these often constructed retaining walls. New types of retaining walls constructed with precast concrete blocks are proposed. This type of retaining wall is incorporates each blocks interconnected with adjacent block by connecting unit to build up a flexible retaining-wall system. This paper focus to behavior characteristics includes deformation and distribution of lateral earth pressure by loading tests and FEM analysis. For model tests, a 1/10 scale reduce models are manufactured include unevenness part, drainage hole and connecting unit and steel wire used to connect each blocks with adjacent block. To simulate the real retaining walls closely, uneven parts are interconnected each other and the construction type of blocks and wall front inclination are varied to investigate the relative displacement of individual block and the location of maximum deformation of wall as increasing surcharging. Additionally, PENTAGON3D, which solve the geotechnical and other problem, used for verifying and comparing with model tests.

• 한국지반신소재학회논문집
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• 제5권3호
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• pp.17-24
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• 2006

본 논문에서는 국내외 두 현장의 보강토옹벽 대한 강우에 의한 영향을 분석한 내용을 다루고 있다. 국내 현장으로 성균관대학교내 지반시험장에 실대형 실험을 목적으로 시공된 계단식 보강토옹벽은 약 8개월 이상 장기 계측을 실시하여 시공시 및 강우시의 계측 결과를 분석 할수 있었다. 국외 보강토옹벽의 현장에서는 강우가 보강토옹벽의 거동에 영향을 미치는 주요인자임을 확인할 수 있었다.

• 한국지반신소재학회논문집
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• 제2권3호
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• pp.47-55
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• 2003

본 고에서는 성균관대학교에 시공된 시험옹벽의 계측결과와 국외에서 발표된 옹벽 붕괴사례를 토대로 강우가 보강토 옹벽의 거동에 미치는 영향을 검토하였다. 시험옹벽에서의 계측결과에서는 집중강우 발생시 벽체 변위 및 보강재의 유발변형율이 증가하는 추세가 뚜렷하게 관찰 되었다. 한편 국외 사례에서도 보강토 옹벽의 붕괴에 있어서 집중강우가 원인을 제공하는 것으로 나타났으며 본 옹벽의 경우 연결강도에 대한 설계가 제대로 이루어지지 않아 강우로 인해 발생한 침투수압에 블록/보강재 연결부가 충분한 저항을 하지 못하여 붕괴가 일어 난것으로 조사되었다. 본 논문에서는 강우와 보강토 옹벽의 거동의 상관관계를 분석 고찰하였다.

• 한국지반환경공학회 논문집
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• 제23권9호
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• pp.25-31
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• 2022

Attaching shelf to retaining structure leads to a decrease in the total lateral earth pressure. This decrease enables the retaining structures to become more stable, to have small displacement, and to exhibit lower bending moments, the relief shelves effects are analyzed using FEM in order to understand how they stabilize cantilever wall in this study. Several models are varied by changing location and width of shelves to realize earth pressure and displacements of retaining wall. The displacement is getting smaller because earth pressure acting on shelf increases as shelves locations are lower and width is longer. The ground settlement variation effects caused by relief shelves are studied also. The ground settlement increases abruptly where shelf location is between of 0.5H and 0.625H, and settlement decreases suddenly where shelf width is between b/h=0.375 and b/h=0.500. The shelf significantly reduces earth pressure and movement of the wall. This decrease in the lateral pressure increases the retaining structure stability.

• 한국지반환경공학회 논문집
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• 제14권9호
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• pp.39-47
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• 2013

Local deformations in back filling materials of two sands and one glass bead with different particle shapes behind a rigid retaining wall were studied. Two kinds of boundary conditions were compared: active wall translation and active rotation of the wall about its toe. Effect of the speed of active wall translation was also investigated. The digital image correlation method was used to analyze local deformation developments inside the materials. Test results showed that particle shape and density mainly influence the inclination angle and width of the shear band. The general shear band pattern is strongly dependent on the wall movement mode, while it was little influenced by particle shape. Within a limited range of wall speed in this study, shear band became wider and local deformation became larger with increase of wall speed.

• Wind and Structures
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• 제22권5호
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• pp.555-571
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• 2016

A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai-Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

• 한국지반공학회지:지반
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• 제5권3호
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• pp.39-50
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• 1989

지진시 벽체의 관성력을 고려하여 소정의 미소변위를 허용하도록 설계된 옹벽의 신뢰도를 해석하는 방법을 연구하였다. FOSM 방법을 Richards and Elms의 model에 적용함으로써 책용적인 옹벽의 신뢰도해석이 가능하였다. 본 연구에서는 우선 지진시의 옹벽설계방법을 고찰하고, 그 다음에 신뢰도 해석방법의 개요를 FOSM을 중심으로 검토하였다. 마지막으로 실제 허용변랍를 인정하는 옹벽의 설계과정과 신뢰도 및 예민도 해석과정을 단계순으로 상세히 제시하여 실용에 편리하게 하였다.