[颜东煌; 王晟; 潘权] Hunan Province University Key Laboratory of Bridge Engineering, Changsha University of Science &, Technology, Changsha, Hunan, 410114, China;[母进伟] Guizhou Highway Engineering Group Co. Ltd., Guiyang, Guizhou, 550008, China;[颜东煌; 王晟; 潘权] School of Civil Engineering and Architecture, Changsha University of Science &, Technology, Changsha, Hunan, 410114, China
Calculation of stayed-buckle cable force is thought as an important content in the raw support cable hoisting method in the construction of CFSTAB. The tensile force of stayed-buckle cable, determined by the project of construction in construction phase, guarantees CFST arch bridge with empty steel tube in fall state to satisfy the designed requirement. Based on the existing algorithm, through ascertaining the influence matrix of the tensile force in the construction of oblique pulling rope, the optimization stayed-buckle cable force is calculated in each hoisting stage of arch rib hoisting construction phase of a model bridge and the designed requirement is fulfilled with empty steel tube in fall state. The method of the raw support cable hoisting is generally used in the construction of long-span CFST arch bridges. The cable-stayed force in the process of segment hoisting is directly relative with the factors such as the control elevation of the segment, the weight of the steel arch rib, cable point and slope angle of stayed-buckle cable etc. Calculation of stayed-buckle cable force has become an important content of construction control.
13th International Conference on Non-Conventional Materials and Technologies: Novel Construction Materials and Technologies for Sustainability, 13NOCMAT 2011
September 22, 2011 - September 24, 2011
Changsha, Hunan, China
(1) School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China; (2) School of Civil Engineering, Changsha University of Science and Technology, Changsha Hunan 410004, China
suspension bridge;girder construction;RCS process;form-finding analysis;model test
The determination of the non-loading condition of the rail cable shifting (RCS) system, which consists of the main cables, hangers, and rail cables, is the premise of girder erection for long-span suspension bridges. An analytical form-finding analysis model of the shifting system is established according to the basic assumptions of flexible cable structures. Herein, the rail cable is discretized into segmental linear cable elements and the main cable is discretized into segmental catenary elements. Moreover, the calculation and analysis equations of each member and their iterative solutions are derived by taking the elastic elongation of the sling into account. In addition, by taking the girder construction of the Aizhai suspension bridge as the engineering background, a global scale model of the RCS system is designed and manufactured. The test system and working conditions are also established. The comparison between the test results and analytical results shows the presented analytical method is correct and effective. The process is simplified in the analytical method, and the computational results and precision satisfy practical engineering requirements. In addition, the proposed method is suitable for application in the computation analysis of similar structures.
[付宏渊; 林鸣; 颜东煌] School of Civil Engineering and Architecture, Changsha University of Science &, Technology, Changsha, 410114, China;[林鸣] Hunan Province Transport Planning, Survey and Design Institute Co., Ltd, Changsha, 410008, China
School of Civil Engineering and Architecture, Changsha University of Science & Technology, Changsha, China
An experimental study is proposed to investigate the high-cycle fatigue behavior of prestressed concrete box-girders. Special focus is on the shear diagonal cracks in the webs of girders, which is rarely investigated in the open literature. Laboratory fatigue tests were designed and conducted to study the propagation of shear diagonal crack of PC box-girder specimens under cyclic loadings. The development of stirrup strain, propagation characteristics of diagonal crack and the related factors are discussed in detail. A finite element (FE) model for concrete damage of PC box girder under high-cycle fatigue loading is established to investigate the crack propagation behavior. Following this, a model for the calculation of diagonal crack widths of PC box-girder under fatigue loading is proposed based on the experimental observations. The calculation results are compared with experimental data for validation. It is observed that the maximum stirrup strain in crack zone increases 67.9% based on this investigation. The ratio of displacement during the last cycle and that during initial loading can research 40.3% in the current investigation. Finally, several conclusions are drawn based on the proposed study. (C) 2017 Elsevier Ltd. All rights reserved.
bridge engineering;cable-stayed bridge;dynamic finite element method;ambient excitation;modal test
To study the stiffness distribution of girder and the method to identify modal parameters of cable-stayed bridge, a simplified dynamical finite element method model named three beams model was established for the girder with double ribs. Based on the simplified model four stiffness formulae were deduced according to Hamilton principle. These formulae reflect well the contribution of the flexural, shearing, free torsion and restricted torsion deformation, respectively. An identification method about modal parameters was put forward by combining method of peak value and power spectral density according to modal test under ambient excitation. The dynamic finite element method analysis and modal test were carried out in a long-span concrete cable-stayed bridge. The results show that the errors of frequencies between theoretical analysis and test results are less than 10% mostly, and the most important modal parameters for cable-stayed bridge are determined to be the longitudinal floating mode, the first vertical flexural mode and the first torsional mode, which demonstrate that the method of stiffness distribution for three beams model is accurate and method to identify modal parameters is effective under ambient excitation modal test.
[涂光亚; 邵旭东] School of Civil Engineering, Hunan University, Changsha 410082, China;[涂光亚; 颜东煌] School of Bridge and Structural Engineering, Changsha University of Science and Technology, Changsha 410076, China
School of Civil Engineering, Hunan University, China