• Title/Summary/Keyword: load interaction

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Effects of Bridge Bearings by Structure-Track Interaction for Continuous Bridge applied CWR with Rail Expansion Joint under Temperature Load (레일신축이음 설치된 장대레일 적용 연속교의 구조물-궤도 상호작용에 의한 온도하중이 교량 받침에 미치는 영향)

  • Chung, Jee-Seung;Lee, Jong-Soon
    • Journal of the Korean Society of Safety
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    • v.25 no.5
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    • pp.54-61
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    • 2010
  • The additional axial force of CWR(continuous welded rail) is occurred by structure-track interaction, in reverse, fixed supports of structure are applied the large load by that. Ratio of load which transferred on support through the bridge superstructure with one-side REJ by acceleration and braking load are stated in High-Speed Rail Design Criteria(2005). On the other hand the horizontal forces of support delivered to the load due to thermal loads has been no report about the criteria. Therefore, this study was performed the review of the reaction and displacement on support by structure-track interaction in a special bridge(composite brdiges, 45+55+55+45=200m) with REJ acting on the temperature load. As a result, because fixed support of a special bridge or a continuous bridge with REJ under the temperature load which is constant load has been acted the large lateral load by structure-track interaction, when determining the fixed bearing capacity of structure should be reflected in the results to secure the safety of structures was confirmed.

Multi-spring model for 3-dimensional analysis of RC members

  • Li, Kang-Ning;Otani, Shunsuke
    • Structural Engineering and Mechanics
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    • v.1 no.1
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    • pp.17-30
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    • 1993
  • A practical multi-spring model is proposed for a nonlinear analysis of reinforced concrete members, especially columns, taking into account the interaction of axial load and bi-directional bending moment. The parameters of the model are determined on the basis of material properties and section geometry. The axial force-moment interaction curve of reinforced concrete sections predicted by the model was shown to agree well with those obtained by the flexural analysis utilizing realistic stress-strain relations of materials. The reliability of the model was also examined with respect to the test of reinforced concrete columns subjected to varying axial load and bi-directional lateral load reversals. The analytical results agreed well with the experiment.

Nonlinear analysis of interaction between flexible pile group and soil

  • Liu, Jie;Li, Q.S.;Wu, Zhe
    • Structural Engineering and Mechanics
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    • v.20 no.5
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    • pp.575-587
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    • 2005
  • Using the nonlinear load transfer function for pile side soil and the linear load transfer function for pile end soil, a combined approach of the incremental load transfer matrix method and the approximate differential equation solution method is presented for the nonlinear analysis of interaction between flexible pile group and soil. The proposed method provides an effective approach for the solution of the nonlinear interaction between flexible pile group under rigid platform and surrounding soil. To verify the accuracy of the proposed method, a static load test for a nine-pile group under a rigid platform is carried out. The finite element analysis is also conducted for comparison purposes. It is found that the results from the proposed method match very well with those from the experimental test and are better in comparison with the finite element method.

Improvement to Crack Retardation Models Using ″Interactive Zone Concept″

  • Lee, Ouk-Sub;Chen, Zhi-Wei
    • International Journal of Precision Engineering and Manufacturing
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    • v.3 no.4
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    • pp.72-77
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    • 2002
  • The load interaction effect can be best illustrated by the phenomenon of overload retardation. Some prediction methods for retardation are reviewed and the problems discussed in the present paper. The so-called under-load effect much of the retardation disappears if a very low level minimum stress follows the overload, is also of importance for a prediction model to work properly under random load spectrum. The concept of Interactive Zone (IZ) fully considering reversed plasticity during unloading was discussed. This IZ concept can be combined with existing models to derive some improved models that can naturally take account of the under-load effect. Some simulations by IZ improved models for test under complex load sequences including multiple overloads and both over/under loads are compared with test results. It is seen that the improvement by IZ concept greatly enhanced the ability of existing models to accommodate complex load interaction effects.

An Analytical and Experimental Wheel Tracking Study on Dynamic Interaction of Vehicle (차량의 동적 상호작용에 관한 이론연구 및 윤하중 실험)

  • Kim, Nak-Suk;Pak, Suk-Soon
    • Journal of the Society of Disaster Information
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    • v.2 no.1
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    • pp.39-52
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    • 2006
  • In this paper, an analytical and experimental study was performed in order to determine the effects of interaction between vehicle and structure. Results presented in the paper show that analytical method including moving load effect can investigate the trend of structural response due to dynamic interaction between vehicle and structure. The wheel tracking machine fitted with 2-axle test vehicle can demonstrate more accurate dynamic interaction between vehicle and structure than the wheel tracking machine fitted without 2-axle test vehicle.

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Evaluation of Seismic Loading of Pile Foundation Structure Considering Soil-foundation-structure Interaction (지반-기초-구조물 상호작용을 고려한 말뚝 기초 구조물에서의 지진 하중 평가)

  • Yoo, Min Taek;Ha, Jeong Gon;Jo, Seong-Bae;Kim, Dong Soo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.18 no.3
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    • pp.125-132
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    • 2014
  • In this study, a series of dynamic centrifuge tests were performed for a soil-foundation-structural interaction system in dry sand with various embedded depths and superstructure conditions. Sinusoidal wave, sweep wave and real earthquake were used as input motion with various input acceleration and frequencies. Based on the results, a natural period and an earthquake load for soil-structure interaction system were evaluated by comparing the free-field and foundation accelerations. The natural period of free field is longer than that of the soil-foundation-structure system. In addition, it is confirmed that the earthquake load for soil-foundation-structure system is smaller than that of free-field in short period region. In contrast, the earthquake load for soil-foundation-structure interaction system is larger than that of free-field in long period region. Therefore, the current seismic design method, applying seismic loading of free-field to foundation, could overly underestimate seismic load and cause unsafe design for long period structures, such as high-rise buildings.

An Analysis of Characteristic of Ice Load Distribution on Model Ship due to Ship and Ice Interaction (빙-선체 상호작용 시 모형선에 작용하는 빙하중 분포 특성 분석)

  • Jeong, Seong-Yeob;Choi, Kyungsik;Cheon, Eun-Jee
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.6
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    • pp.478-484
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    • 2015
  • Knowledge about ice load distribution along the ship hull due to ship-ice interaction can provide important background information for the development of design codes for ice-going vessels. The objective of this study is to understand ship and ice interaction phenomena and determine the magnitude of ice load acting along a ship hull. The model tests were performed in the ice model basin in Korea Research Institute of Ships and Ocean engineering (KRISO) with the model of icebreaking ship Araon. Self-propulsion tests in level ice were performed with three difference model ship speeds. In the model tests, three tactile sensors were installed to measure the spatial distribution of ice load acting at different locations on a model ship, such as the bow and shoulder areas. Variation in the distribution of ice load acting on a model hull with ship speed is discussed.

Interaction of Flexure-Torsional by eccentric load in horizontal curved 'I' shape girder (편심하중이 작용하는 수평 곡선 I 형 거더의 휨·비틀림 상호작용)

  • Lim, Jeong-Hyeon;Lee, Kee-Sei;Kim, Hee-Soo;Choi, Jun-Ho;Kang, Young-Joung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.9
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    • pp.6385-6390
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    • 2015
  • With bending moment, torsional moment due to geometric properties as "Initial curvature" acts in horizontally curved I-girder. These behavior causes the secondary effect of bending in minor-axis because of interaction between bending and torsion. The bending and torsion interaction cause a loss of load bearing capacity by induced the early inelastic or plasticity condition in curved girder. Also eccentric load by movements of traffic can increase torsion. However, Equation of interaction between bending and torsion for straight girder, not deal with characteristics of curved girder behavior in previous studies, can be overestimated for ultimate strength in horizontally curved I-girder acting vertical force. Therefore, using more rational, obvious suggestion is required when design curved girder. In this study, we identified the bending-torsional moment interaction for the horizontally curved I-girder of the eccentric load acting by FEM analysis.

Investigation on Severe Aerodynamic Load Condition about Pantograph (판토그래프 가혹공력하중에 대한 연구)

  • Hwang, Jae-Ho;Lee, Dong-Ho;Chung, Kyung-Ryul
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.361-366
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    • 2001
  • The present study describes a practical estimation procedure about the pantograph under several severe aerodynamic load conditions. As the operating speed of the Korean Train Express(KTX) reaches 350km/h, structural safety at various conditions should be examined at the design stage. In the present study, a compact and reliable procedure is developed to get aerodynamic loads on each part of the pantograph regarding the typhoon condition, the train/tunnel interaction, the train/train interaction and the side wind condition. In the estimation procedure, 3-dimensional steady and unsteady CFD simulation around the high speed train facilitates assigning the external local flow condition around the pantograph. The procedure is verified using the results of the low speed wind tunnel test at JARI and applied to 7 flow conditions and 4 operation configurations.

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Ground vibrations due to underground trains considering soil-tunnel interaction

  • Yang, Y.B.;Hung, H.H.;Hsu, L.C.
    • Interaction and multiscale mechanics
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    • v.1 no.1
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    • pp.157-175
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    • 2008
  • A brief review of the research works on ground vibrations caused by trains moving in underground tunnels is first given. Then, the finite/infinite element approach for simulating the soil-tunnel interaction system with semi-infinite domain is summarized. The tunnel is assumed to be embedded in a homogeneous half-space or stratified soil medium. The train moving underground is modeled as an infinite harmonic line load. Factors considered in the parametric studies include the soil stratum depth, damping ratio and shear modulus of the soil with or without tunnel, and the thickness of the tunnel lining. As far as ground vibration is concerned, the existence of a concrete tunnel may somewhat compensate for the loss due to excavation of the tunnel. For a soil stratum resting on a bedrock, the resonance peak and frequency of the ground vibrations caused by the underground load can be rather accurately predicted by ignoring the existence of the tunnel. Other important findings drawn from the parametric studies are given in the conclusion.