• Title/Summary/Keyword: Underground box structure

Search Result 50, Processing Time 0.028 seconds

A Study on the Structure and Function of the Underground Storage Facility in Baekje (백제 지하저장시설(地下貯藏施設)의 구조와 기능에 대한 검토)

  • Shin, Jong-Kuk
    • Korean Journal of Heritage: History & Science
    • /
    • v.38
    • /
    • pp.129-156
    • /
    • 2005
  • Increasing discovery cases of underground storage facilities made of earth, wood, or stone are being reported from the recent excavation survey of the Baekje relics. Accordingly, the purpose of this study is to examine the structure and function of the underground storage facilities of Baekje following a classification made by the type and building method as follows: plask shape, wooden box shape, and stone box shape. The plask shape storage is the most representative underground storage of Baekje that has been found in numerous relics more than 600 sets around Hangang(Han River) and Geumgang(Geum River) from the Hansung period to Sabi period in Baekje Dynasty. It is a historical artefact as a part of the unique storage culture of Baekje around Hangang and Geumgang from the 3rd to 7th Century. Considering its structure and the example of Chinese one, it might had been used for a long-term storage of grains and various other items including earth wares. The storage facility in wooden box shape and stone box shape are found mostly in the relics Of Sabi period. Thus it might had taken some functions of the storage in traditional pouch shape which had decreased after the 6th Century. In particular, the wooden box shape and stone box shape storage required enormous labor force to build owing to their structure and building method. Thus, they were considered to had been used for official purposes in province fortress and citadel artefact. The wooden box shape storage facility is classified into flat rectangular type and square type based on the structure, and into Gagu type(架構式) and Juheol type(柱穴式) based on the building method. It might had been decided according to the geography and geological feature of the place where the storage was to be built. Considering the examples of Gwanbuk-ri relics and Weolpyong-dong relics, the wooden box shape storage facility might had been used for various items depending on the needs, including foods such as fruits and essential provisions at the military base. Considering the long-term food storage, the examples in Japan, and the functional characteristics of the underground storage facility, there is a possibility that the wooden and stone box shape storage facilities had been built so as to safely store important items in case of fire. This study is only a rudimentary examination for the storage facility in Baekje. Thus further studies are to be made specifically and comprehensively on the comparison with other regions, distribution pattern, discovered relics and artefacts, and functions.

Earth Pressure on the Underground Box Structure (지중 박스구조물에 작용하는 토압)

  • 이상덕
    • Journal of the Korean Geotechnical Society
    • /
    • v.16 no.1
    • /
    • pp.243-250
    • /
    • 2000
  • The mechanical behavior of the underground box culvert constructed by the open cut method depends mainly on the earth pressure acting on it. In this study, the earth pressure on the underground box culverts constructed by the open cut method during and after the construction sequence was numerically analysed by using FLAC. The results are compared with those of the Marston-Spangler's theory, silo theory, and the model tests. The results showed that the vertical earth pressure on the upper slab of the box structure was not uniform. It was as large as the overburden in the middle part of the slab but was smaller or larger than that at its end part depending on the slope of the excavation, the depth of the cover, and the width of the side refill. The horizontal earth pressure on the side wail was much smaller than the earth pressure at rest and grew nonlinearly with the depth.

  • PDF

Nonlinear Earthquake Response Analysis of 2-D Underground Structures with Soil-Structure Interaction Including Separation and Sliding at Interface (지반-구조물 상호작용계의 경계면에서 미끄러짐과 분리현상을 고려한 이차원 지하구조물의 비선형 지진응답해석)

  • 최준성;이종세;김재민
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2002.04a
    • /
    • pp.174-181
    • /
    • 2002
  • The paper presents an effective analytical method for SSI systems which can have separation or sliding at the soil-structure interface. The method is based on a hybrid approach which combines a linear SSI code KIESSI-2D in frequency domain with a commercial finite element package ANSYS to obtain nonlinear dynamic responses in time domain. The method is applied to a 2-D underground box structure which experiences separation and sliding at the soil-structure interface. Material nonlinearity of the concrete structure is also included in the analysis. Effects of the interface conditions are examined and some critical factors affecting the seismic performance of underground structures are identified.

  • PDF

Cast in Place of the Low Heat.Self Consolidation Concrete on Underground RC Box Structure using Low Heat Portland Cement (저열 포틀랜드 시멘트를 활용한 일반강도 저발열.자기충전 콘크리트의 지하박스 구조물 현장적용에 관한 연구)

  • Ha, Jae-Dam;Kwon, Tae-Hoon;Yoo, Sung-Young;Kim, Young-Woo;Kwon, Tae-Moon;Ahn, Byung-Rak
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.215-216
    • /
    • 2009
  • Recently, the application of SCC (Self Consolidation Concrete) gets more necessity, in order to solve the problem of quality control, noise, etc. In this study describe the optimum mix proportion and the experience of cast in place of the SCC in main structure of underground RC box.

  • PDF

Methodology of Parallel Ground Conductor Installation on Underground Transmission System (지중송전 시스템의 병행지선 설치 방안 연구)

  • Hong, Dong-Suk;Park, Sung-Min;Hahn, Kwayng-Hyun
    • Proceedings of the KIEE Conference
    • /
    • 2008.07a
    • /
    • pp.470-471
    • /
    • 2008
  • SVL is installed at underground transmission system to protect cables and insulation joint-box from overvoltages caused by lightning, switching, and line-to-ground fault. Domestic underground power system adopts cross bonding type to reduce the induced voltage at sheath, but single-point bonding is required depending the system installation configuration. SVL can be easily broken by overvoltages induced at joint-box because single-point bonding has uneffective system structure to extract fault current. ANSI/IEEE recommends Parallel Ground Continuity Conductor(PGCC) to prevent SVL breakdown. In this paper, EMTP simulation is performed to analyze effects on SVL under PGCC installation when single-line-to-ground fault occurs. The result shows that PGCC and short single-point bonding distance can reduce overvoltages at SVL.

  • PDF

An Analysis of Safety Zone Appropriateness of Urban Railway Box Structures by Adjacent Excavation Using Machine Learning Technique (머신러닝 기법을 적용한 인접굴착에 따른 도시철도 박스구조물의 안전영역 적정성 분석)

  • Jung-Youl Choi;Jae-Seung Lee;Jee-Seung Chung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.9 no.3
    • /
    • pp.669-676
    • /
    • 2023
  • This study analyzed the relationship between major parameters and numerical analysis results according to various excavations conducted around the urban railway, application of machine learning techniques and verified the scope of influence of the adjacent excavation on the existing urban railway box structure and the appropriateness of the safety area. This study targeted the actual negotiated adjacent excavation works and box structures around the urban railway, and the analysis was conducted on the most representative two-line box structures. The analysis confirmed that the difference in depth of urban railway, excavation depth of adjacent excavation, and depth of underground water level are important parameters, and the difference in excavation depth of adjacent excavation is the parameter that affects the behavior of underground box structures and is an important requirement for setting safety areas. In particular, the deeper the depth of the adjacent excavation work, the greater the effect on the deflection of the underground box structure, and the horizontal separation distance, one of the important requirements for determining the management grade of the existing adjacent excavation work, is relatively small.

Safety assessment of an underground tunnel subjected to missile impact using numerical simulations

  • Thai, Duc-Kien;Nguyen, Duy-Liem;Pham, Thanh-Tung;Pham, Thai-Hoan
    • Computers and Concrete
    • /
    • v.27 no.1
    • /
    • pp.1-12
    • /
    • 2021
  • This work presents a safety assessment of an underground tunnel subjected to a ballistic missile attack employing the numerical approach. For the impact simulation, a box shaped reinforced concrete (RC) structure with a cross section dimension of 8.0×10.0 m under a soil layer that was attacked by a SCUD missile was modeled using finite element (FE) software LS-DYNA. SCUD missile is one of a series of tactical ballistic missiles developed by Soviet Union during the Cold War, which is adopted for a short-range ballistic missile. The developed FE simulation for the penetration depth of the missile impacting into the soil structure was verified from the well-known formula of the penetration prediction. The soil-structure interaction, the soil type, and the impact missile velocity effects on the penetration depth of the missile into the different soil types were investigated. The safety assessment of the underground tunnel was performed with regard to the different depths of the underground tunnel. For each missile velocity and soil type, a specific depth called the unsafe depth was obtained from the analysis results. The structure beneath the soil beyond this depth remains safe. The unsafe depth was found to be increased with the increasing missile velocity.

Experimental and Analytical Evaluation of the Seismic performance of a Concrete Box Structure Strengthened with Pre-flexed Members (프리플렉스 부재를 이용한 콘크리트 박스 구조물 내진보강에 관한 실험 및 해석적 평가)

  • Ann, Ho-June;Song, Sang-Geun;Min, Dae-Hong;An, Sang-Mi;Kong, Jung-Sik
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.29 no.5
    • /
    • pp.397-403
    • /
    • 2016
  • During the rapid economic growth in Korea since the 1970s, many underground facilities were constructed such as under passes and railways. Seismic design has been mandated in 1988, but the structures built before 1988 were not reflected on the seismic design. Accordingly, these underground structures require effective seismic reinforcing methods to ensure safety when the earthquake happens. By these reasons, in this study, using the proposed pre-flexed members, RC box structure was analyzed for seismic reinforcement of the corner. This method is based on a principle that enlarging the resistance against the external force by installing the pre-flexed member to the box structure corner. To evaluate validity, a newly developed member with CornerSafe was compared with traditional type reinforcement using experiments and finite element analysis. In finite element mode, nonlinearity of steel was modeled based on J2 plasticity model and concrete was based on CEB FIP MODEL CODE 1990. Also, composite ratios of box and pre-flexed member were computed for design application. The reinforcement and box structure were analyzed under the bond condition completely attached by the tie, and the results of experiment and finite element analysis were same in the force-displacement curve.

A Case Study on the Feed-Back Analysis and the Reinforcement Plan using the Measurement Data of Excavation Site close to the Existing Underground Box (기존 지하 Box 근접 굴착공사 현장의 계측결과를 이용한 역해석 및 보강방안의 적용 사례)

  • Lee, Jung-Hee;Noh, Won-Seok;Jeong, Soon-Ig;Kim, Wan-Jong
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.09a
    • /
    • pp.445-456
    • /
    • 2010
  • Massive underground excavation can be carried out recently due to the technical development of the excavation for retaining wall. Feed-back analysis using field measurement results is recommended to secure the stability of the construction because calculated values at stages of the design and the construction are uncertain. Reinforcement plan should be established based on the result of it. This study deals with the underground excavation site, which is under construction and is close to structure(subway) at downtown area. The result of feed-back analysis on the measurement data of displacement at multi-soil layers was reflected to make a plan for safe construction. This case study can be useful information for contingency plan on abnormal displacement which can be occurred at similar underground excavation.

  • PDF

Structure movement-coping Waterproofing technology application for Railroad facilities (철도시설에 있어서의 구조물 거동대응형 방수기술의 적용)

  • Cho, Il-Kyu;Lee, Jong-Yong;Oh, Sang-Keun
    • Proceedings of the KSR Conference
    • /
    • 2010.06a
    • /
    • pp.1964-1969
    • /
    • 2010
  • Recently, as construction market scale is getting bigger and transportation industry is developing, the underground structure construction such as subway, tunnel (excavation box) or shield tunnel structure is becoming more diverse, and its demand is gradually increasing. However, for the concrete structures constructed underground, the water leakage is occurred due to the expansion joint and construction joint, or movement, uneven settlement, excessive load and vibration during application causing cracks. Many waterproofing method and materials are used in jobsites, but areas such as underground railroad and subway that has movement and vibration at all times, the ability of waterproofing layer is declined causing repetitive water leakage due to crack, erosion and separation, which is a vicious cycle. Therefore, this study evaluates the responsiveness to a movement for adhesive/flexible waterproofing material that can cope with the vibration and the movement of the structure. Also to recommend a waterproofing technology that can cope with structure movement through examples of actual jobsite applications such as subway and tunnel where there are constant movement and vibration.

  • PDF