• Earthquakes and Structures
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• 제7권6호
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• pp.909-935
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• 2014

The seismic characteristics of two semi-gravity reinforced concrete cantilever retaining walls are examined via an experimental program using an outdoor shake table (one with and the other without concrete masonry sound wall on top). Both walls are backfilled with compacted soil and supported on flexible foundation in a steel soil container. The primary damages during both tests are associated with significant lateral displacements of the wall caused by lateral earth pressure; however, no collapse occurs during the tests. The pressure distribution behind the walls has a nonlinear trend and conventional methods such as Mononobe-Okabe are insufficient for accurate pressure estimation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.87-96
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• 2010

PAP method is a combined measures which consist a anchored retaining wall method with permanent ground anchors and vertical precast concrete panels, step by step on the slope surface. And soil is back filled between slope and vertical precast panels. Therefore, this method is more effective than any other ground anchor reinforcing methods of slope stability, for example cross type concrete block ground anchor or buttress concrete block ground anchor method. Because of increasing effective anchor force and green tree planting.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 사면안정학술발표회
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• pp.3.1-11
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• 2003

Recently the problems related to the failure of the retaining wall structure has become great concern since the damage to the properties and human losses have occurred in the rainy season. However, a detail guideline on safety inspection and appropriate diagnosis on the retaining wall structure have not yet proposed and therefore, the inspection process and results are mainly dependant upon the engineers. The objective of this study is to propose objective and quantitative evaluation method for the condition based on the damage shapes and material types. In this purpose, composing materials of retaining wall are divided Into concrete, gabion, stone and reinforced earth, and then the evaluation items and method are suggested on the basis of the materials and structural characteristics of the retaining wall.

• 한국지반공학회논문집
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• 제21권1호
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• pp.51-58
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• 2005

최근 국내에서는 지오그리드를 사용한 블록형 보강토옹벽 및 교대 옹벽등의 시공이 급속히 증가하는 추세에 있다. 보강토 공법 및 블록형 옹벽의 개념은 역사적으로 상당히 오래된 개념으로 기원전 $2,500{\sim}3,000$년경에 고대 바빌로니아에서 현재의 보강토 공법과 유사한 방법을 사용하였다. 현재 사용되고 있는 블록형 전면블록은 1960년경에 미국에서 콘크리트 크립(crib) 옹벽시스템으로 소개된 이래 활발히 사용되어 왔다. 본 논문에서는 다양한 실험을 통해 보강토 옹벽용 전면블록과 지오그리드 사이의 마찰특성 평가를 수행하였다.

• 한국지반신소재학회논문집
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• 제10권2호
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• pp.81-89
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• 2011

본 연구에서는 국내 간벌 목재를 사용하여 개발한 목재옹벽에 관한 연구를 수행하였다. 목재옹벽은 일반적으로 중력식 옹벽의 설계방법과 동일한 방법으로 설계하고 있지만, 목재틀 전면벽체의 내적안정성에 대한 검토는 일반적으로 수행하고 있지 않다. 본 연구에서는 조적식 콘크리트 블록 옹벽에 적용하고 있는 NCMA(1997)의 내적 안정성 검토 방법을 목재옹벽에 적용할 것을 제안하였다. 또한, 3종류의 목재틀 전면벽체에 대한 전단시험을 수행하여 내적안정을 검토하고 간단한 설계도표를 제안하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1509-1513
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• 2009

The research of applying reinforced retaining wall due to support the land pressure that given from train's load has been accomplished actively in domestic area. After the retaining wall has been installed, the collapse or partial destruction that generated by effect of train's vibration and repetitive load of train may be induced. Accordingly in the period of using this, the sufficient durability should be guaranteed and years of durability are one hundred and as these are longer than road structure's, the technique that introduced to wall and monitor the long-term strain is necessary. In this paper, the optical fibre is induced vertically to the reinforced retaining wall and after the subsistence of optical fibre is confirmed, the early strain that applied to optical fibre after insertion is monitored. Before and after the concrete placing, damage feasibility of optical fibre is measured by using OTDR(Optical Time Domain Reflectometer) and after concrete is cultivated, the early strain induced to optical fibre is measured by application of BOCDA (Brillouin Correlation Domain Analysis) system.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.152-155
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• 2003

The design process of concrete retaining walls includes multiple procedures such as structural analysis, member design, the production of calculation sheets, CAD, and itemized statements of Quantities and costs. The objective of this study is to develope an integrated design system that includes all the steps needed for concrete retaining wall design, and as a result, to improve the quality and efficiency of the design process. In this study, the design steps are divided into structural modules and database, and each module and database is systematically combined for the complete design process. The developed design system is based on Web environment. Therefore it can be used in real time and reduces the design work time and space.

• 농촌계획
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• 제3권2호
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• pp.81-89
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• 1997

Still today, many streams are channelized and embanked in Korea. On the other hand, some urban streams are being restored to their natural shapes by landscape planners. It would be better to improve rural streams in a way that would not require restoration in later days. Then, one important question is what kind of embankments the residents prefer for what reasons. Five simulated photos showing from very natural to artificial embankments were used in surveying 90 residents of three villages. Major findings are ; 1. Residents regard safety(from flooding) is the most critical factor to be considered in selection of stream bank materials. 2. They think ideal materials are natural stones or concrete blocks as they look tidy. Concrete retaining walls or vegetated natural slopes are not regarded good. 3. The most preferred material is concrete retaining wall, and the least preferred is vegetated natural slope. They prefer concrete retaining wall which they do not think an ideal material, because it will make a safe bank. 4. Natural stone bank is most preferred for its apperance, and vegetated natural slpoe is most disliked as it may collapse and as it does not look clean.

• 한국조경학회지
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• 제33권2호
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• pp.32-47
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• 2005

This study was carried out to investigate and propose a green-wall system with evergreen plants for urban greening of Tongyeong City. To achieve these goals, the requirements and possibilities for wall greening were investigated and evaluated considering the location, topography, and climate of Tongyeong City. Existing walls were analyzed and then a suitable green wall system is proposed. Tongyeong City and its 151 islands covers the central and the southern parts of the Goseong peninsula. Most of the land is covered with hills and mountains; $43.9\%$ of the land area has a slope greater than $15\%$ and most hills and mountains near the urban area have a slope of more than $30\%$. As a result of the topographical properties, concrete retaining walls can often be seen along the streets in urbanized areas. These retaining walls are not only unattractive, but they also create environmental problems, and thus should be replaced with native evergreen plants. Options for replacing the retaining walls include evergreen vine-plants such as Hedaa spp. and Euonymus radicans, but native evergreen shrubs such as Pittosporum tobira, Nandina domestica, Raphiolepis umbellata, Ilex cornuta, flex crenata, Fatsia japonic, and Aucuba japonica may be a more attractive option. Current wall conditions are unsuitable for planting vines, therefore, a reservoir-drainage-type plant box filled with a light artificial substrate is required for greening these concrete retaining walls. These might be irrigated in the dry season and fertilized annually by an appropriate system. These plant boxes could be attached along the entire walls. An experiment investigating effects of substrates and bark-chip mulching on the growth of Hedera spp. showed that the mixture of cerasoil and field soil(v/v, 4:6) was superior to field soil alone and to the mixture of perlite small grain, large grain, and field soil(v/v/v, 2:2:6). Bark-chip mulching tended to increase the growth of Hedera spp..

• Steel and Composite Structures
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• 제34권4호
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• pp.525-545
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• 2020

This paper presents a new structural system to use as retaining walls. In civil works, there is a general trend to use traditional reinforced concrete (RC) retaining walls to resist soil pressure. Despite their good resistance, RC retaining walls have some disadvantages such as need for huge temporary formworks, high dense reinforcing, low construction speed, etc. In the present work, a composite wall with only one steel plate (steel-concrete) is proposed to address the disadvantages of the RC walls. In the proposed system, steel plate is utilized not only as tensile reinforcement but also as a permanent formwork for the concrete. In order to evaluate the efficiency of the proposed SC composite system, an experimental program that includes nine SC composite wall specimens is developed. In this experimental study, the effects of different parameters such as distance between shear connectors, length of shear connectors, concrete ultimate strength, use of compressive steel plate and compressive steel reinforcement are investigated. In addition, a 3D finite element (FE) model for SC composite walls is proposed using the finite element program ABAQUS and load-displacement curves from FE analyses were compared against results obtained from physical testing. In all cases, the proposed FE model is reasonably accurate to predict the behavior of SC composite walls under out-of-plane loads. Results from experimental work and numerical study show that the SC composite wall system has high strength and ductile behavior under flexural loads. Furthermore, the design equations based on ACI code for calculating out-ofplate flexural and shear strength of SC composite walls are presented and compared to experimental database.