• Title/Summary/Keyword: concrete lining

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Evaluation of Tunnel Lining Concrete Using Ultrasonic Pulse Velocity Method (초음파법을 이용한 무근콘크리트 터널라이닝의 품질평가)

  • 최홍식;이시우;신용석;오영석;오광진
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.795-800
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    • 2001
  • Two evaluation techniques of the tunnel lining concrete using ultra sonic velocity method are developed. Modified linear regression technique is proposed to enhance the corelation between the pulse velocity and the compressive strength of core specimens. And bivariate normal distribution is assumed to evaluate the quality of concrete as a terms of compressive strength. A simple corelation table between the pulse velocity and the compressive strength of core specimens are proposed.

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Fire Resistance Performance of Precast Segmental Concrete Lining for Shield Tunnel (쉴드 터널용 프리캐스트 세그먼트 콘크리트 라이닝의 내화성능)

  • Han, Byung-Chan;Harada, kazunori;Kwon, Young-Jin;Kim, Yun Yong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.1
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    • pp.95-105
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    • 2014
  • Reinforced concrete (RC) shield tunnel lining must be designed for fireproof performance because the lining is sometimes exposed to very high temperature due to traffic accidents. Both experimental and numerical studies are carried out to evaluate fire resistance performance of precast RC tunnel lining systems. In the experimental studies, six full-scale precast RC tunnel segments are exposed to fire in order to examine the influence of various parameters on the fire resistance performance of precast RC tunnel lining. We used the temperature curve of the RABT criteria, which are severe conditions of fire temperatures. The fire test showed that the explosive spalling was not observed by substituting concrete to PP fiber reinforced concrete. A transient heat flow analysis was carried out in consideration of the material properties that change with temperature, and the results showed good agreement with the test results.

Case Studies of Automatic Measurement and strength for Damage in the Public Tunnel (공용중인 터널의 변상에 대한 보강 및 자동화계측 사례)

  • Han Ja-Jung;Kim Young-Ho;Jang Gi-Soo;Kweon Young-Jung;Ahn Sang-Ro
    • 한국터널공학회:학술대회논문집
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    • 2005.04a
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    • pp.270-281
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    • 2005
  • An especial attention for old tunnel safety is required on increasing of The various tunnel recently. Specially, the lining investigation method of the old tunnel will be able to presume condition of concrete lining indirectly. Because it is many restriction thought of environment and ground condition investigation method of tunnel lining rear. This study carried out section & convergence measurement of part which was deformed in tunnel lining. It had been observed for the change of tunnel behavior with a continuous measurement. It has been analyzed for a cause of tunnel deformation and inspected for the effect after a repair-reinforcement to tunnel compared with the effect before those by structure analysis. By establishing automatic measurement system after repair-reinforcement to tunnel, it would be accomplished to convergence measurement continually. As a result, it was observed that deflection and deformation of tunnel was convergent. but it should be followed to a continuous maintenance because of unstable ground condition, cause of inner tunnel, environment. The railroad tunnel which was executed a reinforcement of the tunnel lining must investigate the close condition of reinforcement lining and concrete lining.

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A Study on Crack Control of Tunnel Lining Concrete with Large Section (대단면 터널 라이닝 콘크리트의 균열저감 연구)

  • Kim, Wan-Young
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.509-512
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    • 2008
  • The lining concrete of water tunnel is a much capability to occur crack due to drying shrinkage and vibrator compaction etc. Because of crack of concrete induce structural problem and decrease durability of concrete, it is need to reduce crack of concrete. In this an Analytical study to analyze the effect of curing of concrete and compaction on the lining concrete. As the results, it was found that control of construction condition into curing of concrete and compaction improve on construction efficiency of the lining concrete.

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Development of Inspection System for Crack on the Lining of Concrete Tunnel (콘크리트 터널 라이닝 균열검사 시스템 개발에 관한 연구)

  • 고봉수;손영갑;신동익;김병화;한창수
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.1
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    • pp.66-72
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    • 2004
  • To assess tunnel safety, cracks in tunnel lining are measured by inspectors, who observe cracks with their naked eyes and record them. But manual inspection is slow, and measured crack data is subjective. Therefore, this study proposes inspection system fur measuring cracks in tunnel lining and providing objective crack data to be used in safety assessment. The system consists of On-vehicle system and Laboratory system. On-Vehicle system acquires image data with line CCD camera on scanning along the tunnel lining. Laboratory system extracts crack information from the acquired image using image processing. Measured crack information is crack thickness, length and orientation. To improve accuracy of crack recognition, the geometric properties and patterns of cracks in concrete structure were applied to image processing. The proposed system was verified with experiments in both laboratory environment and field environment such as subway tunnel.

Simplified nonlinear simulation for composite segmental lining of rectangular shield tunnels

  • Zhao, Huiling;Liu, Xian;Yuan, Yong
    • Structural Engineering and Mechanics
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    • v.81 no.4
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    • pp.513-522
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    • 2022
  • Steel-concrete composite segments replacing the conventional reinforced concrete segments can provide the rectangular shield tunnel superiorities on bearing capacity, ductility and economy. A simplified model with high-efficiency on computation is proposed for investigating the nonlinear response of the rectangular tunnel lining composed of composite segments. The simulation model is developed by an assembly of nonlinear fiber beam elements and spring elements to express the transfer mechanism of forces through components of composite segments, and radial joints. The simulation is conducted with the considerations of material nonlinearity and geometric nonlinearity associated with the whole loading process. The validity of the model is evaluated through comparison of the proposed nonlinear simulation with results obtained from the full-scale test of the segmental tunnel lining. Furthermore, a parameter study is conducted by means of the simplified model. The results show that the stiffness of the radial joint at haunch of the ling and the thickness of inner steel plate of segments have remarkable influence on the behaviour of the lining.

A Study on the Expansion Joint of Concrete Lining and Duct in a Tunnel (터널 콘크리트 라이닝 및 공동구 신축이음 설치방안에 관한 연구)

  • Son, Moorak;Park, Yangheum;Park, Yunjae;Kim, Jaegyoun;Yoon, Jongcheol
    • Journal of the Korean Geotechnical Society
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    • v.31 no.3
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    • pp.39-50
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    • 2015
  • The installation of the expansion joints in a tunnel concrete lining and duct would minimize the cracking at the location of structural shape and stiffness change, differential settlement, big temperature change, and so on. However, it is difficult to determine the required spacing of the expansion joint in a tunnel concrete lining and duct quantitatively because the spacing is influenced by temperature change, structure construction condition, ground-structure interaction, and etc. Nevertheless, a highway specification (Korea Expressway Corporation, 2012) or a road design manual (Ministry of Land, Transport and Maritime Affairs, 2010) specifies that the expansion joint spacing in a tunnel concrete lining should be installed uniformly smaller than 25 m from the tunnel portals to 50 m inside of a tunnel and elsewhre 20-60 m in a tunnel (because there is no specifcation for a duct it is assumed that a duct follows the specfication of lining). This specification results in several construction and economic problems in relation with a tunnel construction. Accordingly, in order to minimize the problems, this study analyzed both domestic and foreign design standards and specifications. In addition, field test, theoretical and numerical analyses were carried out in relation to the expansion joint in a tunnel lining and duct. The purpose of this study is to reestabilish a criterion for installing the expansion joint in a tunnel concrete lining and duct.

An Experimental Study on Performance of neater Stops at Construction joints in Tunnel (터널 시공이음부에서의 방수재 역할에 대한 실험연구)

  • 백송훈
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.10a
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    • pp.217-223
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    • 1999
  • Mostly, water leakage took place in construction joints. In case of cable tunnels constructed by open-cut method, waterstops have been used to prevent the water leakage. But, we haven't any experience to install the waterstops in NATM cable tunnels. So, it is necessary to develope the waterstops and test the performance of it in laboratory. We manufactured cable tunnel lining quarter scale model by pouring concrete, and installed the waterstops. After filling the inside of concrete lining about two-third with water, we put the air pressure on the water, In addition, it is also carried out water leakage test for concrete lining model without waterstops. As a result, we confirmed the performance of waterstops and its adaptability. It is also tested that the performance of rubber gaskets used in concrete segments of Shield tunnelling. In addition, we determined the allowable infiltration rate for cable tunnel with non-drainage system.

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