• Journal of the Korean Geosynthetics Society
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• v.4 no.3
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• pp.35-43
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• 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.

• Journal of the Korean Geotechnical Society
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• v.32 no.12
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• pp.45-57
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• 2016

The Inclined Earth Retaining Structure (IER) is the structure using an integrated system of both front supports and inclined back supports to increase the stability for excavation. The IER is a structurally stable temporary excavation method using the back supports restraining the lateral displacement of the front supports as stabilizing piles. The back supports connected to the front supports significantly reduce the earth pressure acting on both the front wall and the front supports by distributing it to the back supports in order to increase the structural stability. In this study, mechanical behaviors of IER according to the head connection type using fixed- or hinge-connection were found by performing numerical analysis and laboratory model tests in the sandy ground. The maximum lateral displacement of fixed-connection was 88% of that of hinge-connection in the numerical analysis. The lateral displacement of fixed-connection was 7% of that of hinge-connection in the laboratory model test results. Furthermore, the earth pressure of the fixed-connection was 67% of that of the hinge-connection in the shear-strain analysis results of the model ground.

• Journal of the Korean Geotechnical Society
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• v.37 no.8
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• pp.37-49
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• 2021

A retaining wall system is widely constructed civil structure to maximize the effectiveness of practical use of the land. Recently, the technology which is more eco-friendly and owns seismic stability of the retaining wall system becomes important. In this study, an Eco-BELT system using natural rocks as the front wall is introduced and the seismic characteristics of the Eco-BELT system are analyzed based on 2 and 3 dimensional numerical analysis. The soil-structure interface comprises between backfill soil and natural rocks are considered. The relative density is mainly considered to influence the seismic behavior of Eco-BELT system, and T-shaped deadman is also considered to judge the increase of seismic stability. As a result, lateral displacement of the wall decreases 29.5% in maximum under 90% of relative density and decreases 21.2 to 21.9% with T-shaped deadman, therefore, the seismic effectiveness of T-shaped deadman and increasing relative density of backfill are verified by numerical analysis.

• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.171-186
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• 2010

It is generally known that the mechanism of behavior in the flexible earth retaining system is relatively more complicated than in the rigid earth retaining system. Moreover in the case of long span strut supporting system the analysis of strut axial force change becomes more difficult when the differences of ground condition and excavation work progress on both sides of excavation section are added. When deeper excavation than the specification or installation delay of supporting system or change of ground condition happen during construction process, lots of axial force can be induced in some struts, which threaten the safety of construction. This paper introduces two examples of long span deep excavation where struts and rock bolts were used as a supporting system with flexible wall structure. The characteristics of ground deformation and strut axial force change, which were measured in the sections of two examples that are 50 meters apart in one construction site and have almost similar design and construction conditions were analysed, the similarity and difference between measurement results of two examples were compared and investigated. This article aims to improve and develop the technique of design and construction in future projects having similar ground condition and supporting method.

• Anatomy and Cell Biology
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• v.57 no.1
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• pp.25-30
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• 2024

The aim of this study was to identify the anatomical feature of retaining ligament and fat compartment on the lower eyelid and infraorbital region using a histological method, and to investigate clear definitions for them which could be used generally in the clinical area. Eighteen specimens from eight fresh Korean cadavers were stained with Masson trichrome or hematoxylin and eosin. The ligamentous and fascial fibrous tissue were clearly identified. The ligamentous fibrous tissue which traversed in the superficial and deep fat layer was skin ligament and orbicularis retaining ligament (ORL). The fascial fibrous tissue enclosed the orbicularis oculi muscle (OOc) and circumferencial adipose tissue. Based on the ligamentous and fascial structure, three fat compartments, septal, suborbicularis oculi and infraorbital fat compartment, could be identified. The OOc attached to orbital rim and dermis by ORL and skin ligament, and the muscle fascicle and fat fascicle provided the connection point to the ORL and skin ligament as enclosing all muscle and fat tissue. The combination of the force made by the skin ligament in the lower eyelid and ORL may decide the level and form of the infraorbital grooves.

• Journal of the Korean Institute of Rural Architecture
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• v.1 no.3
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• pp.13-26
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• 1999

This study lays emphasis on the traditional houses of Hongsung, Poryoung which were hardly studied. The method of investigation is to grasp the type, the present condition, and the feature of the traditional houses through sample survey. This study lays emphasis on two myon of Hongsung, Poryoung retaining their original form relatively through sample survey. The houses of investigation subject involve the houses in which structure change is not big of repair and improved houses centering around houses confirmed things built in late-Chosun. The method of investigation is to consider survey, materials for research work, and literature and is to grasp the substance of houses through analysis of arrangement, plane, and structure.

• Journal of Aerospace System Engineering
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• v.6 no.3
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• pp.13-18
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• 2012

Every 3000 hour an aircraft is stricken by a lightning. Also the lightning damage to the aircraft during flight are continually occurred due to extreme weather phenomena such as global warming. Under the airworthiness standards, the aircraft must be designed to protect lightning. To show compliance for lightning, the test should be conducted by the actual lightning current and voltage waveform for the actual aircraft or parts. After test, structure damage is detected via visual inspection or NDI. Structure substantiation for damage is to show retaining limit or near limit load capability. This is conducted by test or analysis based on test. Thus, the aircraft should retain structural strength to land safely, even though the damage of aircraft fuselage from Lightning strike are occurred.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.111-118
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• 1994

The use of steel sheet pile walls as barrier walls have the temporary for coffer dam, retaining wall in excavation, etc., but also permanent of semi-permanent for harbor construction, containment systems, vertical barrier systems for waste disposal (landfill) or subway in excavarion. In all these applicaions the resistance of the structure to seepage plays an important role. Also the stability and longevity of the construction, the possibility of permanent control and survey make the steel sheet pile wall a nearly perfect vertical barrier from a technical and economical point of view.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.289-294
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• 1997

매스콘크리트 구조물에서는 이미 경화된 콘크리트가 새로이 타설된 콘크리트의 변형을 제한하여 시공직후에 부재의 길이방향에 수직한 균열이 발생하는 경우가 자주 보고 되고 있다. 이 균열은 먼저 타설된 바닥에 대하여 벽체의 변위가 제한될 때 구속인장응력에 의해 발생된다. 이러한 균열의 발생원인은 몇 가지로 살펴볼 수 있는데, 그 하나는 먼저 타설한 바닥 콘크리트와 새로 타설한 벽체 콘크리트와의 수화열 발생의 차이에 의한 것이며, 두번째 이유로 바닥과 벽체사이의 건조수축의 차이를 들 수 있다. (중략)

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.3-14
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• 2005

Reliable predictions of the movement of earth retaining structures and the ground adjacent to braced walls in urban excavation are often difficult due to many variable factors. The ground settlement and the damage of adjacent structures in urban excavation has been an important issue. Therefore, the stability of the adjacent structures must be secured with the excavation support and research on the protection of adjacent structure is necessary. This study showed an urban excavation case and introduce observation method for case of damage behavior in urban excavation.