• Title, Summary, Keyword: cable stiffness

Search Result 178, Processing Time 0.043 seconds

Load deformation characteristics of shallow suspension footbridge with reverse profiled pre-tensioned cables

  • Huang, Ming-Hui;Thambiratnam, David P.;Perera, Nimal J.
    • Structural Engineering and Mechanics
    • /
    • v.21 no.4
    • /
    • pp.375-392
    • /
    • 2005
  • Cable supported structures offer an elegant and economical solution for bridging over long spans with resultant low material content and ease of construction. In this paper, a model of shallow cable supported footbridge with reverse profiled pre-tensioned cables is treated and its load deformation characteristics under different quasi-static loads are investigated. Effects of important parameters such as cable sag and pre-tension are also studied. Numerical results performed on a 3D model show that structural stiffness of this bridge (model) depends not only on the cable sag and cross sectional areas of the cables, but also on the pre-tension in the reverse profiled cables. The tension in the top supporting cables can be adjusted to a high level by the pre-tension in the reverse profiled bottom cables, with the total horizontal force in the bridge structure remaining reasonably constant. It is also evident that pre-tensioned horizontally profiled cables can greatly increase the lateral horizontal stiffness and suppress the lateral horizontal deflection induced by eccentric vertical loads.

Wind-resistant performance of cable-supported bridges using carbon fiber reinforced polymer cables

  • Zhang, Xin-Jun;Ying, Lei-Dong
    • Wind and Structures
    • /
    • v.10 no.2
    • /
    • pp.121-133
    • /
    • 2007
  • To gain understanding of the applicability of carbon fiber reinforced polymer (CFRP) cable in cable-supported bridges, based on the Runyang Bridge and Jinsha Bridge, a suspension bridge using CFRP cables and a cable-stayed bridge using CFRP stay cables are schemed, in which the cable's cross-sectional area is determined by the principle of equivalent axial stiffness. Numerical investigations on the dynamic behavior, aerostatic and aerodynamic stability of the two bridges are conducted by 3D nonlinear analysis, and the effect of different cable materials on the wind resistance is discussed. The results show that as CFRP cables are used in cable-supported bridges, (1) structural natural frequencies are all increased, and particularly great increase of the torsional frequency occurs for suspension bridges; (2) under the static wind action, structural deformation is increased, however its aerostatic stability is basically remained the same as that of the case with steel cables; (3) for suspension bridge, its aerodynamic stability is superior to that of the case with steel cables, but for cable-stayed bridge, it is basically the same as that of the case with steel stay cables. Therefore as far as the wind resistance is considered, the use of CFRP cables in cable-supported bridges is feasible, and the cable's cross-sectional area should be determined by the principle of equivalent axial stiffness.

An investigation on the mechanical properties of cable stitches in weft knitting (위편성 케이블 조직의 편성법에 따른 물성 평가)

  • Choi, Wonseok
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.20 no.4
    • /
    • pp.73-82
    • /
    • 2018
  • This research investigated the mechanical properties of the 4 different types of $3{\times}3$ cable stitches on weft knitted fabrics. The 4 kinds of cable-stitch fabrics were knitted under the same knitting conditions, then the mechanical properties, such as tensile strength, elongation, stiffness, etc. were measured according to the Korean Industrial Standards (KS K 0642). The knitting time for the sample produced by the knitting process 1 was the shortest among the 4 different types of samples. It means that the knitting process 1 would have benefits of higher productivity if there is no yarn breakage during the knitting of the cable stitches. In the test for tensile strength, the samples produced by knitting processes 3 and 4 have tensile values of approximately 8~11% higher than the sample produced by knitting process 1. The test for elongation also shows that the samples produced by knitting processes 3 and 4 have up to 18% higher elongation values than the sample produced by knitting process 1. On the other hand, the stiffness test showed no significant difference between the 4 samples. This study is expected to increase the competitiveness of the local knitting industry as a result of providing basic data on the mechanical properties of special knitted stitches, such as cable stitches.

Elastic porabolic element for initial shaping analysis of cable-stayed bridges (사장교의 초기형상해석을 위한 탄성포물선요소)

  • Kyung Yong-Soo;Kim Ho-Kyung;Kim Moon-Young
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • /
    • pp.481-488
    • /
    • 2005
  • This study presents a elastic parabolic cable element for initial shaping analysis of cable structures. First, the compatibility condition and the tangent stiffness matrices of the elastic catenary cable element are shortly summarized. Next the force-deformation relations and the tangent stiffness matrices of the elastic parabolic cable elements are derived from the assumption that sag configuration under self-weights is small. To confirm the accuracy of this element, initial shaping analysis of cable-stayed bridges under dead loads is executed. Finally, the accuracy and the validity of the analysis-results are compared and analyzed through numerical examples.

  • PDF

A dynamic finite element method for the estimation of cable tension

  • Huang, Yonghui;Gan, Quan;Huang, Shiping;Wang, Ronghui
    • Structural Engineering and Mechanics
    • /
    • v.68 no.4
    • /
    • pp.399-408
    • /
    • 2018
  • Cable supported structures have been widely used in civil engineering. Cable tension estimation has great importance in cable supported structures' analysis, ranging from design to construction and from inspection to maintenance. Even though the Bernoulli-Euler beam element is commonly used in the traditional finite element method for calculation of frequency and cable tension estimation, many elements must be meshed to achieve accurate results, leading to expensive computation. To improve the accuracy and efficiency, a dynamic finite element method for estimation of cable tension is proposed. In this method, following the dynamic stiffness matrix method, frequency-dependent shape functions are adopted to derive the stiffness and mass matrices of an exact beam element that can be used for natural frequency calculation and cable tension estimation. An iterative algorithm is used for the exact beam element to determine both the exact natural frequencies and the cable tension. Illustrative examples show that, compared with the cable tension estimation method using the conventional beam element, the proposed method has a distinct advantage regarding the accuracy and the computational time.

An Elastic Parabolic Cable Element for Initial Shaping Analysis of Cable-Stayed Bridges (사장교의 초기형상해석을 위한 탄성포물선 케이블요소)

  • Kyung, Yong-Soo;Kim, Moon-Young
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.20 no.1
    • /
    • pp.1-7
    • /
    • 2007
  • This study introduces an elastic parabolic cable element for initial shaping analysis of cable-stayed bridges. First, an elastic catenary cable theory is shortly summarized by deriving the compatibility condition and the tangent stiffness matrices of the elastic catenary cable element. Next, the force-deformation relations and the tangent stiffness matrices of the elastic parabolic cable elements are derived from the assumption that sag configuration under self-weights is small. In addition the equivalent cable tension is defined in the chord-wise direction. Finally, to confirm the accuracy of this element, initial shaping analysis of cable-stayed bridges under dead loads is executed using TCUD in which stay cables are modeled by an elastic parabolic cable and an elastic catenary cable element, respectively. Resultantly it turns that unstrained lengths of stay cables, the equivalent cable tensions, and maximum tensions by the parabolic cable element are nearly the same as those by the catenary cable elements.

Nonlinear Analysis of IPS System using the multi-noded cable element (다절점 케이블요소를 이용한 IPS 시스템의 비선형 해석)

  • Lee Jun-Seok;Kim Moon-Young;Han Man-Yop;Kim Sung-Bo;Kim Nak-Kyung
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • /
    • pp.623-630
    • /
    • 2006
  • In this paper, a geometric nonlinear analysis procedure of beam-column element including multi-noded cable element is presented. For this, first a stiffness matrix about beam-column element which considers the second effect of initial force supposing the curved shape at each time step with Hermitian polynomials as the shape function is derived and second, tangent stiffness matrix about multi-noded cable element being too. To verify geometric nonlinearity of this newly developed multi-noded cable-truss element, IPS(Innovative Prestressed Support) system using this theory is analysed by geometric nonlinear method and the results are compared with those by linear analysis.

  • PDF

Diagonal bracing of steel frames with multi-cable arrangements

  • Husem, Metin;Demir, Serhat;Park, Hong G.;Cosgun, Suleyman I.
    • Structural Engineering and Mechanics
    • /
    • v.59 no.6
    • /
    • pp.1121-1137
    • /
    • 2016
  • A large number of structure in the world were build with poor seismic details, with or without any lateral load resisting system like concentrically braced frames and steel plate shear walls. These structures can reveal deteriorating hysteretic behaviors with stiffness and strength degradation. Therefore, seismic retrofitting of such structures for drift control has vital importance. In this study a retrofit methodology has been developed, which involves diagonal bracing of steel frames with different cable arrangements. In the experimental and numerical program 5 different lateral load resisting system were tested and results compared with each other. The results indicated that multi-cable arrangements suggested in this study showed stable ductile behavior without any sudden decrease in strength. Due to the usage of more than one diagonal cable, fracture of any cable did not significantly affect the overall strength and deformation capacity of the system. In cable braced systems damages concentrated in the boundary zones of the cables and beams. That is why boundary zone must have enough stiffness and strength to resist tension field action of cables.

Development of Cable Damper System and Its Verification Test (사장교 케이블 댐퍼시스템 개발과 검증실험)

  • Seo, Ju-Won;Kim, Nam-Sik;Suh, Jeong-Gin;Jeong, Woon
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • /
    • pp.394-402
    • /
    • 2001
  • In order to lessen cable vibration, new cable damper system with high damping rubber was developed using the basis of the LRB design scheme. The analysis model of cable damper system incorporate voigt-kelvin damper model into the nonlinear cable analysis model. To achieve maximum damping capacity both reducing damper stiffness and developing high damping rubber were performed. As a result of verification test, the high damping rubber damper show its effectiveness in improving cable damping capacity.

  • PDF

Mechanics feasibility of using CFRP cables in super long-span cable-stayed bridges

  • Zhang, Xin-Jun
    • Structural Engineering and Mechanics
    • /
    • v.29 no.5
    • /
    • pp.567-579
    • /
    • 2008
  • To gain understanding of the applicability of CFRP cables in super long-span cable-stayed bridges, by taking a 1400 m cable-stayed bridge as example, mechanics performance including the static behavior under service load, dynamic behavior, wind stability and seismic behavior of the bridge using either steel or CFRP cables are investigated numerically and compared. The results show that viewed from the aspect of mechanics performance, the use of CFRP cables in super long-span cable-stayed bridges is feasible, and the cross-sectional areas of CFRP cables should be determined by the principle of equivalent axial stiffness.