• Title/Summary/Keyword: axial force

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Power Transmission Characteristics and Speed Ratio-Torque Load-Axial Force Relationship for a Metal V-Belt CVT (금속 V-벨트 CVT의 동력전달 특성과 변속비-부하토크-축력 관계)

  • 김광원;김현수
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.2
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    • pp.349-357
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    • 1990
  • Power transmission characteristics and speed ratio-torque load-axial force relationship for a metal V-belt CVT were investigated theoretically and experimentally. In the metal V-belt CVT drive, it was found that the power was transmitted by thrust force and that band tension should be greater than compression force between the metal blocks. The experimental results for the speed ratio-torque load-axial force relationship showed good agreement with those predicted using equations developed from theoretical considerations.

Vibrations of a taut horizontal cable subjected to axial support excitations considering nonlinear quasi-static responses

  • Jiang Yi;Yingqi Liu
    • Structural Engineering and Mechanics
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    • v.86 no.2
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    • pp.221-235
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    • 2023
  • To calculate the vibrations of a tout cable subjected to axial support excitations, a nonlinear relationship of cable force and the support displacement under static situations are employed to depict the quasi-static vibration of the cable. The dynamic components of quasi-static vibration are inputted as "direct loads" to cause the parametric vibrations on the cable. Both the governing equations of motion and deformation compatibility for parametric vibrations are then derived, which indicates the high coupling of cable parametric force and deformation. Numerical solutions, based on the finite difference method, are put forward for the parametric vibrations, which is validated by the finite element method under periodic axial support excitations. For the quasi-static response, the shorter cables are more sensitive to support excitations than longer ones at small cable force. The quasi-static cable force makes the greatest contribution to the total cable force, but the parametric cable force is responsible for the occurrence of cable loosening at large excitation amplitudes. Moreover, this study also revealed that the traditional approach, assuming a linear relationship between quasi-static cable force and axial support displacement, would result in some great error of the cable parametric responses.

The Behavior of Local Buckling for Steel Circular Tubes Subject to Cyclic Axial Loads (반복 축하중을 받아 국부좌굴을 수반하는 원형강관 부재의 복원력 특성)

  • Lee Sang-Ju;Lee Dong-Woo;Han Sang-Eul
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.347-354
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    • 2006
  • In this paper, we work with steel circular tubes and propose analysis model which can consider local buckling that it has an effect on failure of steel structures and induce the relation between loading and deformation. First of all, in respect to axial symmetry local buckling, which is simplest case, elasto-plastic behavior acting only axial loads is object Therefore, it suggests analysis model for axial symmetry local buckling. And that is explainable the process from increasing internal force to decreasing passing maximum internal force. Besides, we induce the relation between the axial force and axial deformation.

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Post-buckling behaviours of axially restrained steel columns in fire

  • Li, Guo-Qiang;Wang, Peijun;Hou, Hetao
    • Steel and Composite Structures
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    • v.9 no.2
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    • pp.89-101
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    • 2009
  • This paper presents a simplified model to study post-buckling behaviours of the axially restrained steel column at elevated temperatures in fire. The contribution of axial deformation to the curvature of column section is included in theoretical equations. The possible unloading at the convex side of the column when buckling occurs is considered in the stress-strain relationship of steel at elevated temperatures. Parameters that affect structural behaviours of the axial restrained column in fire are studied. The axial restraint cause an increase in the axial force before the column buckles; the buckling temperature of restrained columns will be lower than non-restrained steel columns. However, the axial force of a restrained column decreases after the column buckles with the elevation of temperatures, so make use of the post-buckling behaviour can increase the critical temperature of restrained columns. Columns with temperature gradient across the section will produce lower axial force at elevated temperatures.

Behaviour of flush end-plate beam-to-column joints under bending and axial force

  • da Silva, Luis Simoes;de Lima, Luciano R.O.;da S. Vellasco, Pedro C.G.;de Andrade, Sebastiao A.L.
    • Steel and Composite Structures
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    • v.4 no.2
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    • pp.77-94
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    • 2004
  • Steel beam-to-column joints are often subjected to a combination of bending and axial forces. The level of axial forces in the joint may be significant, typical of pitched-roof portal frames, sway frames or frames with incomplete floors. Current specifications for steel joints do not take into account the presence of axial forces (tension and/or compression) in the joints. A single empirical limitation of 10% of the beam's plastic axial capacity is the only enforced provision in Annex J of Eurocode 3. The objective of the present paper is to describe some experimental and numerical work carried out at the University of Coimbra to try to extend the philosophy of the component method to deal with the combined action bending moment and axial force.

Evaluation of Axial Strains of Reinforced Concrete Columns (철근콘크리트 기둥의 축방향 변형률 평가)

  • Lee, Jung-Yoon;Kim, Min-Ok;Kim, Hyung-Beom
    • Journal of the Korea Concrete Institute
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    • v.25 no.1
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    • pp.19-28
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    • 2013
  • The longitudinal axial strain in the plastic hinge region of reinforced concrete (RC) columns influences on the structural behavior of RC structures subjected to reversed cyclic loading. This strain decreases the effective compressive strength of concrete and increases the lateral displacements between stories by causing the elongation of member length. This paper investigated the effects of the axial force on the elongation of a RC member by using a sectional analysis of RC members. The analytical and experimental results indicated that the axial force decreased the axial strain in the plastic hinge region of RC columns. In this study, a model was proposed to predict the axial strain of RC columns. The proposed model considering the effects of axial force ratio consisted of three path types ; Path 1-loading region, Path 2-unloading region, and Path 3-reversing cyclic loading region. The axal strains predicted by the proposed model were compared with the test results of RC columns with various axial force ratios, and agreed reasonably with the observed longitudinal strains.

Comparison of speed ratio-torque load-axial force characteristics and their performance for automotive rubber and metal V-belt CVT (차량용 고무 및 금속 V-벨트 CVT의 변속비-부하토크-축력특성과 성능비교)

  • 김현수;김광원
    • Journal of the korean Society of Automotive Engineers
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    • v.12 no.3
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    • pp.9-20
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    • 1990
  • The speed ratio-torque load-axial force characteristics of a rubber V-belt (RVB) and a metal V-belt (MVB) CVT are investigated and their performances are compared. It is found that power is transmitted by tension difference in RVB, and by thrust difference in MVB. The nondimensional equations for speed ratio-torque load-axial force of RVB are exactly same as those of MVB. However, actual characteristics of axial forces of RVB and MVB are different depending on their power transmission methods. The torque capacity of MVB is 5-6 times higher than that of RVB due to MVB's higher strength, even if the required axial force of MVB CVT control is 3-4 times higher than that of RVB.

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Variation of Rail's Axial Compressive Force on Railway Bridges Due to Thermal and Seismic Loads with using EQS Bearings (EQS 면진받침 사용 시 온도하중 및 지진하중에 대한 철도교량 레일 압축력 변화)

  • Kim Lee Hyeon;Kim Haksoo;Choi Eunsoo
    • Journal of the Korean Society for Railway
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    • v.8 no.3
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    • pp.276-285
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    • 2005
  • This study discussed the effect on rail's axial force due to thermal and seismic loads according to supporting conditions of railway bridges; the considered supporting conditions are 1)simply supported, 2)roller at both ends, and 3)roller with horizontal spring at both ends. Closed form solutions are used to calculate the axial farces on rails. The roller at both ends of a bridge span decreases the compressive axial force on rail due to thermal load compared with the simply supported condition. However, the lateral springs at roller are not helpful to decrease the rail's compressive axial force.

Free Vibration of Tapered Beams Under Tensile Axial Force (軸引張力을 받는 變斷面 보의 自由振動)

  • Lee, Byeong-Gu;Kim, Yeon-Tae;Mo, Jeong-Man
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.34 no.1
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    • pp.57-65
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    • 1992
  • The main purpose of this paper is to present both the natural frequencies and mode shapes of tapered beams under tensile axial force. The differential equation governing planar free vibration for tapered beams under tensile axial force is derived as nondimensional form. The three kinds of cross sectional shape are considered in differential equation. The Runge-Kutta method and Determinant Search method are used to perform the integration of the differential equation and to determine the natural frequencies, respectively. The hinged-hinged, hinged-clamped, clamped-clamped and constraints are applied in numerical examples. The lowest four nondimensional natural frequencies are reported as the function of nondimensional tensile axial force. The fundamental natural frequencies are presented when section ratios and nondimensional axial forces are varied. The effects of cross sectional shapes are reported and some typical mode shapes are also presented.

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Study on seismic performance of exterior reinforced concrete beam-column joint under variable loading speeds or axial forces

  • Guoxi Fan;Wantong Xiang;Debin Wang;Zichen Dou;Xiaocheng Tang
    • Earthquakes and Structures
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    • v.26 no.1
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    • pp.31-48
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    • 2024
  • In order to get a better understanding of seismic performance of exterior beam-column joint, reciprocating loading tests with variable loading speeds or axial forces were carried out. The main findings indicate that only few cracks exist on the surface of the joint core area, while the plastic hinge region at the beam end is seriously damaged. The damage of the specimen is more serious with the increase of the upper limit of variable axial force. The deflection ductility coefficient of specimen decreases to various degrees after the upper limit of variable axial force increases. In addition, the higher the loading speed is, the lower the deflection ductility coefficient of the specimen is. The stiffness of the specimen decreases as the upper limit of variable axial force or the loading speed increase. Compared to the influence of variable axial force, the influence of the loading speed on the stiffness degradation of the specimen is more obvious. The cumulative energy dissipation and the equivalent viscous damping coefficient of specimen decrease with the increase of loading speed. The influence of variable axial force on the energy dissipation of specimen varies under different loading speeds. Based on the truss model, the biaxial stress criterion, the Rankine criterion, the Kent-Scott-Park model, the equivalent theorem of shearing stress, the softened strut-and-tie model, the controlled slip theory and the proposed equations, a calculation method for the shear capacity is proposed with satisfactory prediction results.