• Title/Summary/Keyword: 동적 접지력

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Estimation of Slab Response of Plate Girder Bridge in Traffic-Induced Vibration by Three-Dimensional Analysis (삼차원 해석에 의한 강합성교 바닥판의 교통유발진동 응답 평가)

  • Kim, Chul Woo;Kawatani, Mitsuo;Lee, Woo Hyun
    • Journal of Korean Society of Steel Construction
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    • v.10 no.2 s.35
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    • pp.263-277
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    • 1998
  • Recently, it is frequently reported that fatigue damages of deck slabs and floor systems of highway bridges occur under the conditions of increasing weight and traffic of heavy vehicles. These troubles are affected by dynamic wheel load of heavy vehicles running on roadway surface roughness with bump at expansion joint. It is required that this kind of traffic-induced vibration of highway bridges must be analyzed by using three-dimensional models of bridge and vehicle. In this study, the three-dimensional dynamic analysis is carried out, and dynamic responses of deck slab and wheel loads of moving vehicle are estimated according to different vehicle speeds and bump heights. Analytical responses of bridge deck slab are compared with experimental ones which were measured at Umeda entrance bridge of Hanshin Expressway in Osaka.

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A Study on the Dynamic Wheel Loads of 3-D Vehicle Model Considering Tire Enveloping (타이어 접지폭을 고려한 3차원 차량모델에 의한 동적 차륜하중에 관한 연구)

  • Chung, Tae Ju
    • Journal of Korean Society of Steel Construction
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    • v.14 no.1
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    • pp.95-104
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    • 2002
  • In this paper, research for dynamic wheel loads of 3-D vehicle model considering tire enveloping model is carried out. Heavy trucks with 2-axles and 3-axles are modeled by 7-d.o.f. and 8-d.o.f., in which contact length of tire and pitching of tandem spring axles is considered. Dynamic equations of vehicle are derived by using the Lagrange's equation and solution of the equation is calculated by 5th Runge-Kutter method. The validity of the developed 3-D vehicle model is demonstrated by comparing the results obtained by the present method and experimental data by Whittemore. The maximum impact factors of tire force are calculated when vehicle models of 8ton and 15ton dump truck are running on the different class roads with 1.0km and on the various step bump.

A Study on the Dynamic Response of Highway Bridges by 4-Axles Single Truck (4축 단일차량에 의한 도로교의 동적응답에 관한 연구)

  • Chung, Tae-Ju
    • Journal of Korean Society of Steel Construction
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    • v.23 no.3
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    • pp.397-404
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    • 2011
  • In this paper, a research for the dynamic wheel loads of a 3D vehicle model, which relates to a tire-enveloping model, is carried out. A single truck with four axles is modeled as a 10-D.O.F. vehicle by modeling both contact length of tires and pitching of tandem spring axles. The dynamic equations of the vehicle are obtained using the Lagrange's equation, the solution of the equations is calculated by Newmark-${\beta}$ method. The validity of the developed 3D vehicle model is demonstrated by comparing results obtained from the proposed method with those from experimental data. The maximum impact factors of tire force are evaluated according to the various step bumps on which a 24-ton dump truck is running.

Dynamic Response Analysis of AGT Vehicle Considering Surface Roughness of Railway (노면 요철을 고려한 AGT 차량의 동적 응답 해석)

  • Song, Jae-Pil;Kim, Chul-Woo;Kim, Ki-Bong
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.12
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    • pp.986-993
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    • 2002
  • The equations of motion for an automated guide-way transit(AGT) system running on a path with roughness have been derived to investigate dynamic responses and wheel loads of moving vehicles of the AGT system. A vehicle of the AGT system is idealized as three-dimensional model with 11 degree-of-freedom. The computer program is developed to solve the dynamic equations, and anlatical results are verified by comparing the results with experimental oness. Parametric studies are carried out to investigate the dynamic responses of an AGT vehicle according to vehicle speeds, surface roughness, damping and stiffness of suspension systems. The parametric study demonstrates that amplitudes of dynamic responses and the wheel loads have a tendency to increase according to travel speeds, the stiffness of suspension system and surface roughness. On the other hand. those amplitudes tend to decrease according to increase of damping of the suspension system.

Dynamic Bearing Pressure of Inverted T-type Retaining Walls Subjected to Seismic Motion (지진시 동토압을 받는 역 T형 옹벽의 접지압 산정에 관한 연구)

  • Lee, Jin-Sun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.16 no.2
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    • pp.35-45
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    • 2012
  • Pseudo static analysis using the Mononobe-Okabe method and numerical analysis considering a small strain nonlinearity from the soil were performed to determine the bearing pressure changes of the inverted T-type retaining wall subjected to earthquake motions. In many cases, an inverted 'T' type retaining wall of more than 10 m shows bearing capacity failure under earthquake conditions, despite showing sufficient bearing capacity during normal conditions. The most important reason for this is the change of the effective base area during an earthquake. In this paper, the change of the effective base area of an inverted 'T' type wall is analyzed by using finite difference element code (FLAC). In addition, the effect of dynamic bearing capacity coefficients (which has been suggested by several researchers but not adopted in current design codes and procedures) was verified.

The Effects of Design Parameter Uncertainty of the Shock Absorber on the Performance of Suspension System (충격 흡수기의 설계 파라미터 불확실성이 현가 장치 성능에 미치는 영향)

  • Lee, Choon-Tae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.5
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    • pp.949-958
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    • 2020
  • The functions of shock absorbers are to dampen body, suspend motions, dissipate impact energy, and control tire force variation. During the operation, hydraulic oil is passed between the chambers via a flow restrictions. Therefore the damping force characteristics of shock absorber is determined by the characteristics of orifices and flow restrictions. The uncertainty in design variable affects the performance of suspension system strongly. But, the researches about the influence of uncertainty in design variable such as a fluid restriction's property of shock absorber, on the suspension system performance was hardly ever proposed. In this paper, we used statistical method of Latin Hypercube sampling, and the effects of design variables uncertainty on the performance of suspension system was presented.