• Journal of Power System Engineering
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• v.14 no.2
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• pp.65-70
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• 2010

Retaining rings are used to support the field winding end turns from the centrifugal force by the high speed of the field and these are the overstressed parts among the generator parts. There have been several retaining failures in Europe and America, all attributable to stress corrosion cracking in 18Mn-5Cr steel. Since then, each manufacture companies have developed a good 18Mn-5Cr steel in temperature, strength characteristic and it is used in many field now. From many findings and test results, we could conformed that the failure might be grown in the overstressed condition unrelated to the moisture particle.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.21-24
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• 2009

This study deals with the application of USN wireless inclinometer sensor for earth retaining structure safety measurement, The application of wireless inclinometer sensor has great advantage about real-time monitoring of earth retaining structure, It allows a construction manager to monitor movement data from anywhere connected through internet during the process of excavation for substructures of buildings, To validate the applicability of the wireless inclinometer sensor. laboratory and field tests have been performed, The results have shown that the measured values of wireless inclinometer sensor represent the behavior of H-pile well, Both convenience of sensor installation and real-time monitoring of earth retaining structure are confirmed, The proposed wireless measurement system provides a good basis for exact measurement of temporary substructures, More measurements and application are expected for the other excavation sites with various conditions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.207-215
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• 2003

Developed is a new environment-friendly concrete-block retaining wall system. The conventional analysis methods are not directly applicable because the proposed concrete-block wall system is made of by interlocking the blocks with shear keys. Therefore, the shear analysis as well as stability analysis have been conducted to secure the safety of block-wall system. Overall slope stability analysis was also performed. An appropriate strengthening method was developed to ensure the safety when the block-wall system is relatively high. The method of analysis for strengthening the concrete-block wall system was also proposed. The proposed environment-friendly concrete block retaining wall system shows reasonable safety and can be a good construction method for retaining walls and river bank walls.

• Geomechanics and Engineering
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• v.16 no.3
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• pp.321-329
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• 2018

Classic braced walls use struts and wales to minimize ground movements induced by deep excavation. However, the installation of struts and wales is a time-consuming process and confines the work space. To secure a work space around the retaining structure, an anchoring system works in conjunction with a braced wall. However, anchoring cannot perform well when the shear strength of soil is low. In such a case, innovative retaining systems are required in excavation. This study proposes an innovative earth-retaining wall that uses in situ soil confined in dual sheet piles as a structural component. A numerical study was conducted to evaluate the stability of the proposed structure in cohesionless dry soil and establish a design chart. The displacement and factor of safety of the structural member were monitored and evaluated. According to the results, an increase in the clearance distance increases the depth of safe excavation. For a conservative design to secure the stability of the earth-retaining structure in cohesionless dry soil, the clearance distance should exceed 2 m, and the embedded depth should exceed 40% of the wall height. The results suggest that the proposed method can be used for 14 m of excavation without any internal support structure. The design chart can be used for the preliminary design of an earth-retaining structure using in situ soil with dual steel sheet piles in cohesionless dry soil.

• Journal of the Korean Institute of Rural Architecture
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• v.2 no.2
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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.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.41-44
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• 2000

This paper represent about design of the controller for battery of a reflector of retaining wall for power supply using PV Module. Simulation is represents V-I and power characteristic by Mathematica & Design Cneter 6.3 & Qnet 2.1 Finally we composed of road surface-signpost system. This system is successfully operating with high clearness lights.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.517-520
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• 2013

In construction operation, the temporary structure is used to support designed facilities or to provide work spaces for construction activities. Since the structure is used only during the construction operation, the operation may be given insufficient attention. The contractor is likely to try to save cost on the material and labor cost. This contractor's behavior frequently leads to construction accidents. In order to prevent accidents from the failure, the operation should be carefully monitored for identifying the effect of dynamics in the surrounding site area. Otherwise, any unexpected adversary effect could result in a very costly construction failure. This study presents the feasibility of the ubiquitous sensor network (USN) technology in collecting construction data during the construction operation of earth retaining walls. The study is based on the result at the Construction System Integration Laboratory (CSIL) at the Pusan National University. A USN-based system has been developed for monitoring the behavior of the temporary structure of earth retaining walls. The data collected from the sensors were used to understand the behavior of the temporary structure. The result of this study will be used in increasing the safety during the construction operation of retaining walls.

• International Journal of Railway
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• v.6 no.3
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• pp.107-111
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• 2013

In order to constrain the railway roadbed settlement which causes track irregularity, and thus threats running stability and ride quality, advanced Back-to-Back (BTB) reinforced retaining wall was numerically analyzed as railway roadbed structure. This study is intended to improve conventional Back-to-Back reinforced retaining wall as the technology which would reduce the roadbed settlement in a way of constraining the lateral displacement of its prestressed vertical facing and inducing arching effects in roadbed (backfill) placed between masonry diaphragm wall and vertical facing. As a result of numerical analysis, it was found that the roadbed settlement was reduced by 10% due to the prestressed vertical facing and embedded masonry diaphragm wall of the advanced Back-to-Back reinforced retaining wall system.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1039-1049
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• 2010

Excavation support systems are the temporary earth retaining structures that can prevent the lateral movement of soils. The systems are initially performed before other construction operations and have a great impact on the entire construction period. The temporary support system in Korea have been carried out generally along with installing supports, which are struts, tiebacks, and rakers. However, most of existing support systems in application relatively have limitations such as cost increase, construction configuration, and displacement occurred with support systems. Thus, a new retaining support system (referred to as the SSR, New Construction Technology No. 533) was developed to solve the aforementioned problems. This study introduces the design, construction, and maintenance of the SSR system under the different construction conditions. The behavior and characteristics of the SSR system were identified based on the case studies.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.2
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• pp.167-174
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• 2002

Earth retaining structure is constructed structure in order to construct a multistoried building, the subway, a subterranean downtown for effective use and obtainments of the limited ground. Recently, many kinds of research have been actively developed for a standardization and a database on designing and constructing of bridge, tunnel, road. With the works of database construction of that, many kinds of data with respect to statistics is cumulated. However, Database work of designed and constructed earth retaining structure in the construction field is wholly lacking and lagged behind in the works of database construction. This paper suggested classification system on indication data in connection with designing and constructing earth retaining structures a hundred fields. On the basis of that, code work with classification system was practised and DB program of indication data in connection with designing and constructing earth retaining structures was developed.