• Journal of the Earthquake Engineering Society of Korea
• /
• v.8 no.2
• /
• pp.9-17
• /
• 2004

The seismic performance evaluation and retrofit process are very important in old existing bridges. If the result is not appropriate. then a retrofit process are required. Among various retrofit methods, the seismic isolation is a very useful method. because it can be applied by replacing old bridge bearings. In this study, the effectiveness of seismic isolation is rationally verified. For this purpose, two seismic isolations used widely are selected and non-linear static and dynamic analyses are performed. The responses of existing bridges are compared with those of retrofited bridges by seismic isolation bridge for earthquake of target level. and seismic performances are evaluated.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.6C
• /
• pp.385-393
• /
• 2006

Soil nailing is a reinforcement method used for stabilizing excavated walls or slopes. Due to its much advantages such as ease of construction and economical efficiency, use of soil nailing is increased. However, the soil nail has much disadvantages for use in urban area. The soil nail needs to be installed inevitably beyond private land boundary, which causes rent for use. For this reason, removable soil nailing system was developed. However, the removal rate of this system is just about 50￠¦70%. To resolve this problem, the Fiber Reinforced Plastic (FRP) soil nailing system which does not need to be removed and allows for the installation beyond private land, is developed. In this paper, through theoretical and experimental studies in laboratory and field such as prototype tests, pullout tests, we evaluate the stability and behavior characteristics of the FRP soil nailing system. And, numerical analyses using FLAC2D were performed with respect to various soil conditions, where prototype test for excavation wall and pullout tests were carried out. As a result of this study, the FRP soil nailing systems show similar behavior characteristics with those of removable soil nailing system. Finally, considering the serviceability and mechanical stability of FRP soil nailing systems, it is enough to be used as a good alternative of general soil nailing system.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.1C
• /
• pp.53-63
• /
• 2011

This paper investigates the effects of tunnelling-induced ground movements on nearby structures, considering soil-structure interactions of different ground (loose sand, dense sand, soft clay, stiff clay) and construction conditions (ground loss). The response of four-story block structures, which are subjected to tunnelling-induced ground movements, has been investigated in different ground and construction conditions (ground loss) using numerical analysis. The structures for numerical analysis has been modelled using Discrete Element Method (DEM) to have real cracks when the shear and tensile stress exceed the maximum shear and tensile strength. The response of four-story block structures has been investigated with a ground movement magnitude and compared in terms of ground and construction conditions (ground loss) considering the magnitude of deformations and cracks in structures. In addition, the damage levels, which are possibly induced in structures, has been provided in terms of ground and construction conditions (ground loss) using the state of strain damage estimation criterion (Son and Cording, 2005). The results of this study will provide a background for better understandings for controlling and minimizing building damage on nearby structures due to tunnelling-induced ground movements.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.6C
• /
• pp.255-263
• /
• 2010

This paper investigates the effects of tunnelling-induced ground movements on nearby structures, considering soil-structure interactions of different construction (ground loss) and soil characteristics. The response of four-story block structures, which are subjected to tunnelling-induced ground movements, has been investigated in different construction (ground loss) and soil conditions using numerical analysis. The structures for numerical analysis has been modelled using Discrete Element Method (DEM) to have real cracks when the shear and tensile stress exceed the maximum shear and tensile strength. The response of four-story block structures has been investigated with a ground movement magnitude and compared in terms of construction (ground loss) and soil conditions considering the magnitude of deformations and cracks in structures. In addition, the damage levels, which are possibly induced in structures, has been provided in terms of construction (ground loss) and soil conditions using the state of strain damage estimation criterion (Son and Cording, 2005). The results of this study will provide a background for better understandings for controlling and minimizing building damage on nearby structures due to tunnelling-induced ground movements.

• Journal of the Korean Geotechnical Society
• /
• v.20 no.1
• /
• pp.49-59
• /
• 2004

A GIS-based tunnelling risk management system(GIS-TURIMS) was developed as a product of this study, The developed system uses ArcView 8.1 as a basic platform and the built-in interface(VBA) has been used to perform first-order simplified analyses for the prediction of tunnelling-induced ground movements and building damage assessment. The main emphasis of this study was to develop a working framework that can be used in the perspective of tunnelling risk management. The developed system is capable of carrying out cornputationally intensive analyses for ground movement prediction as well as buildings/utilities damage assessment taking full advantage of the GIS technologies. This paper describes the concept and details of the GIS-TURIMS development and implementation.

• Journal of the Korean Geosynthetics Society
• /
• v.3 no.1
• /
• pp.27-36
• /
• 2004

This paper presents the results of stability analyses on soil-reinforced segmental retaining walls in a tiered arrangement. Four different walls were examined to investigate the appropriateness of their designs within the context of the current design guidelines based on limit equilibrium. Slope stability analysis against the compound failure mode, which is frequently ignored during design, was also performed based on the method recommended by FHWA design guidelines. Also presented are the results of instrumentation on a full-scale field trial wall constructed as part of this study. The implications of the findings from this study are discussed.

• Journal of the Korea Institute of Building Construction
• /
• v.24 no.4
• /
• pp.413-424
• /
• 2024

To expedite construction of small precast concrete buildings using dry joints, this study developed and evaluated a connector system for solid slabs. The research included a comprehensive literature review on seismic design requirements for precast concrete floors, followed by an analytical evaluation of the connector's bearing capacity in 3-story buildings. Experimental assessments were conducted to determine the in-plane and out-of-plane capacities of the newly designed semi-circular connector. Finally, the constructability of both the semi-circular and flat connector configurations was compared through tests on single-story precast concrete frames.

• Tunnel and Underground Space
• /
• v.17 no.5
• /
• pp.428-434
• /
• 2007

Displacement of tunnel face is important issues for the evaluation of tunnel safety. In this study, conventional convergence and displacement data measured from horizontal inclinometer were analyzed to investigate the trend and characteristics of tunnel deformation during construction. Trend of measured displacement agreed with general understanding of tunnel deformation prior to excavation. It shows that displacement measured from horizontal inclinometer can be used to preestimate the total deformation of tunnel.

• Journal of Korean Association for Spatial Structures
• /
• v.6 no.1 s.19
• /
• pp.65-73
• /
• 2006

In these days the floor vibration is beginning to make its appearance of the environmental dispute in dwelling building. Standard floor system are suggested for the settlement of this issue by government. The sound of floor impact sound is needed to secure comfortable quality in housing. Also, it is required an accurate analysis and a proper evaluation for floor vibration. Refine model is necessary for the floor system of housing to analyze accurately the floor vibration. But this refine model is not efficient because it is required so much running time for vibration analysis and it is difficult of modeling of standard floor slab. In this paper, new modeling methods of standard floor slab are proposed for the accurate rigidity evaluation. By using the new modeling method, the accurate vibration response can be obtained and can accurately evaluate the rigidity of standard floor system with resilient materials. Therefore the proposed modeling method is of practical use for vibration analysis of floor system of housing.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2011.05a
• /
• pp.136-136
• /
• 2011

최근, 수자원의 효율적 이용을 위하여 농업용수로를 파이프라인으로 시공하는 지구가 증가하는 추세에 있다. 한편으로는 간척지를 복합농업단지, 시설원예, 신재생에너지단지 등 다각적으로 이용하는 정책을 추진하고 있다. 이에 따라, 농업용수 공급시스템도 개수로에서 관수로로 설계하는 추세에 있다. 농업분야에서 관수로를 활용하기 시작한 것은 ‘80년대 중반부터이나 그간 관수로 설계기준의 부재, 시범사업의 실패 등으로 인하여 보급이 지연되어 왔다. 일반적으로 관수로 설계는 노선선정, 관조직 구성, 관경산정, 관망해석, 도면작성 등 일련의 과정을 거쳐야 완성된다. 이 설계과정에서 관경산정 및 관망해석은 고도의 설계 노하우가 없으면 활용이 어려운 설계기술이다. 이번에 개발한 관수로 설계지원시스템은 관수로 설계 전문가가 처리해야할 일련의 설계작업을 AUTO CAD상에서 일관성 있게 처리할 수 있도록 개발한 것이 특징이다. 관수로설계지원시스템은 수치지도상에서 등고선 좌표, 표고 등을 자동 추출하여 사업계획서 및 종단도를 작성할 수 있으며, 관망심볼을 이용하여 시스템상에서 관망조직을 구성할 수 있으며, 다양한 안에 대한 노선검토, 관경산정, 관망해석과 관두께, 매설심도 등 구조해석이 가능하다. 그리고, 농업용 관수로의 제수밸브 등 부대시설에 대한 표준도를 D/B로 작성하여 설계도 작성시 참고할 수 있도록 개발하였다. 관수로설계지원시스템은 매뉴얼대로 처리하면 관망해석에 대한 전문지식이 없어도 설계에 활용이 가능하다.