Analysis on Aerostatic Response for Hongkong-Zhuhai-Macao Great Bridge in Construction Stage

2013 ◽  
Vol 455 ◽  
pp. 220-223
Author(s):  
Yu Li ◽  
Sen Wang ◽  
Yan Yang Che
Keyword(s):  
Parametric Design ◽  
Research Result ◽  
Three Dimensional ◽  
Vertical Displacement ◽  
Construction Stage ◽  
Long Span ◽  
Fea Model ◽  
Section Model ◽  
Left And Right ◽  
Torsion Deformation

Based on the wind tunnel experiment for aerostatic force of section model of Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in construction stage, one calculation program considering the geometric nonlinearity and aerostatic nonlinearity is prepared by using ANSYS parametric design language in order to calculate the nonlinear aerostatic response for long-span cable-stay bridges. Then, the FEA model of Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in construction stage is established to analyze the three-dimensional nonlinear aerostatic stability. And the aerostatic response with different position of bridge is also calculated. The research result indicates that the aerostatic instability can not occur in Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in its construction stage. And, the max torsion deformation, transverse and vertical displacement of construction stage occur in the terminal edge of both left and right span and decreases gradually near to main tower.

Analysis on Aerostatic Stability for Jianghai Direct Ship Channel Bridge in Finished Stage

2014 ◽  
Vol 989-994 ◽  
pp. 986-989
Author(s):  
Li Yu ◽  
Sen Wang ◽  
Yan Yang Che ◽  
Guo Hui Zhao
Keyword(s):  
Geometric Nonlinearity ◽  
Parametric Design ◽  
Research Result ◽  
Three Dimensional ◽  
Long Span ◽  
Fea Model ◽  
Vertical Displacements ◽  
Section Model ◽  
Ansys Parametric Design Language ◽  
Torsion Deformation

Based on the wind tunnel experiment for aerostatic force of section model of Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in its finished stage, one calculation program considering the geometric nonlinearity and aerostatic nonlinearity is prepared by using ANSYS parametric design language in order to calculate the nonlinear aerostatic response for long-span cable-stay bridges. Then, the FEA model of Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in its finished stage is established to analyze the three-dimensional nonlinear aerostatic stability. And the aerostatic response with different position of bridge is also calculated. The research result indicates that the aerostatic instability can not occur in Jianghai direct ship channel bridge of Hongkong-zhuhai-macau great bridge in its finished stage. And, the max torsion deformation, transverse and vertical displacements of finished stage occur in the mid-span of each span and decrease gradually near to both sides.

scholarly journals Numerical Analysis of Long-Span Cable-Stayed Bridge in the Construction Phase

2015 ◽  
Vol 9 (1) ◽  
pp. 896-905 ◽  
Author(s):  
Xue Chengfeng ◽  
Liu Laijun ◽  
Wu Fangwen ◽  
Yang Caofang
Keyword(s):  
Parametric Design ◽  
Tension Stress ◽  
Construction Stage ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Fea Model ◽  
Temperature Method ◽  
Cable Force ◽  
Sutong Bridge ◽  
Stage Analysis

The fabrication and erection of cable-stayed bridges involve major changes in structure configuration through the addition and removal of structure components. In every stage of the construction process, adequate information on the constructed structure is important to determine the real structure situation for the analysis of errors and to verify construction requirements. The ultimate goals are to meet construction needs and identify the effects of modification in subsequent construction procedures. The final configuration of the structure is strongly dependent on the construction and fabrication procedures. In this regard, developing an FEA model to simulate the actual construction processes is necessary to determine the performance of a bridge under external loads. In this study, a general methodology for construction processes is presented to simulate a cable-stayed bridge. The stage-by-stage construction of the Sutong Bridge is simulated with ANSYS software package. The tensions of cables are realized with ANSYS parametric design language, element birth and death function, and mutliframe restart function. The objective of the construction stage simulation is to identify stresses and deformations of the steel box girder and the concrete towers, as well as the cable tension stress, to meet the design requirements. Results of the construction stage analysis showed that the temperature method could simulate the adjustment of the inclined cable force successfully, and the global stiffness of the Sutong Bridge was very small before closure. These findings served as the initial data for a dynamic research on the Sutong cable-stayed bridge.

The Seismic Response Analysis of Long-Span Cable-Stayed Bridge

2014 ◽  
Vol 501-504 ◽  
pp. 1364-1367
Author(s):  
Yong Zhe Niu ◽  
Wen Jie Guo ◽  
Guang Ling Li ◽  
Rui Xin Sun
Keyword(s):  
Seismic Response ◽  
Lateral Displacement ◽  
Response Spectrum ◽  
Three Dimensional ◽  
Vertical Displacement ◽  
Response Analysis ◽  
Element Analysis ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Seismic Property

Anti-seismic property was essential in the progress of bridge designing and construction due to destructive power of earthquake disaster and increasing span of bridge. This paper elaborated theory method of analysis, taking five spans continuous cable-stayed bridge which was half floating system as an engineering background, and using method of special finite element analysis to calculating dynamic characteristics and seismic response respectively which also considered longitudinal limit damping and stiffness of cable under longitudinal, transverse, vertical and three-dimensional seismic oscillation. Fundamental frequency of cable-stayed bridge was affected significantly with considering longitudinal limit damping, so connection measures would be determined reasonably in designing and analyzing anti-seismic property of long-span cable-stayed bridge. When response spectrum analysis was adopted, longitudinal and vertical displacement were larger than lateral displacement under longitudinal seismic oscillation, lateral seismic oscillation only affected the structural lateral displacement, and vertical seismic oscillation affected vertical and longitudinal displacement.

The three-dimensional structure of frozen-hydrated left- and right-handed forms of bacterial flagellar filaments from an identical serotype

1986 ◽  
Vol 44 ◽  
pp. 298-299
Author(s):  
S. Trachtenberg ◽  
D. J. DeRosier
Keyword(s):  
Ionic Strength ◽  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Protein Species ◽  
Liquid Environment ◽  
Bacterial Flagellum ◽  
Left And Right ◽  
Rotary Motor ◽  
Helical Parameters

The bacterial cell is propelled through the liquid environment by means of one or more rotating flagella. The bacterial flagellum is composed of a basal body (rotary motor), hook (universal coupler), and filament (propellor). The filament is a rigid helical assembly of only one protein species — flagellin. The filament can adopt different morphologies and change, reversibly, its helical parameters (pitch and hand) as a function of mechanical stress and chemical changes (pH, ionic strength) in the environment.

Development of program-driven plug-in for conical counter-rotating twin screw based on SolidWorks

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Liqun Dong ◽  
Junwei Zhang ◽  
Liang Qin ◽  
Ping Xue ◽  
Yun Ma ◽  
...  
Keyword(s):  
Parametric Design ◽  
Cone Angle ◽  
Three Dimensional ◽  
Visual Basic ◽  
Automatic Generation ◽  
Three Dimensional Model ◽  
Modeling Process ◽  
Basic Language ◽  
Twin Screw ◽  
Visual Basic Language

Abstract Owing to the existence of the cone angle, the size of a conical counter-rotating twin screw continuously changes along the axis, so it is not easy to model using SolidWorks. In this study, the parametric design of the modeling process is completed based on the Visual Basic language and a program-driven method. Finally, the SolidWorks program plug-in and user interface are developed to complete the automatic generation of the three-dimensional model of a conical counter-rotating twin screw.

Effect of Residual Stress or Plastic Deformation History on Fatigue Life Simulation of Pipeline Dents

2018 ◽  
Author(s):  
Xian-Kui Zhu ◽  
Rick Wang
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Fatigue Life ◽  
Residual Stresses ◽  
Three Dimensional ◽  
Strain History ◽  
Deformation History ◽  
Stress Strain ◽  
Element Analysis ◽  
Fea Model

Mechanical dents often occur in transmission pipelines, and are recognized as one of major threats to pipeline integrity because of the potential fatigue failure due to cyclic pressures. With matured in-line-inspection (ILI) technology, mechanical dents can be identified from the ILI runs. Based on ILI measured dent profiles, finite element analysis (FEA) is commonly used to simulate stresses and strains in a dent, and to predict fatigue life of the dented pipeline. However, the dent profile defined by ILI data is a purely geometric shape without residual stresses nor plastic deformation history, and is different from its actual dent that contains residual stresses/strains due to dent creation and re-rounding. As a result, the FEA results of an ILI dent may not represent those of the actual dent, and may lead to inaccurate or incorrect results. To investigate the effect of residual stress or plastic deformation history on mechanics responses and fatigue life of an actual dent, three dent models are considered in this paper: (a) a true dent with residual stresses and dent formation history, (b) a purely geometric dent having the true dent profile with all stress/strain history removed from it, and (c) a purely geometric dent having an ILI defined dent profile with all stress/strain history removed from it. Using a three-dimensional FEA model, those three dents are simulated in the elastic-plastic conditions. The FEA results showed that the two geometric dents determine significantly different stresses and strains in comparison to those in the true dent, and overpredict the fatigue life or burst pressure of the true dent. On this basis, suggestions are made on how to use the ILI data to predict the dent fatigue life.

Seismic Response Analysis of CFST Arch Bridge Considering Input Earthquake Characteristics

2011 ◽  
Vol 255-260 ◽  
pp. 962-966
Author(s):  
Fan Xing ◽  
Lin Zhao ◽  
Ya Zhe Xing
Keyword(s):  
Seismic Response ◽  
Research Result ◽  
Steel Tube ◽  
Response Analysis ◽  
Vibration Period ◽  
Arch Bridge ◽  
Near Fault ◽  
Long Span ◽  
Cfst Arch Bridge ◽  
Out Of Plane

In view of huge destructibility of the near-fault ground motions, structures with long natural vibration period are liable to fall into nonlinear reaction stage. Based on a full understanding of the near-fault seismic spectrum characteristics, the out-of-plane seismic response of a long span concrete-filled steel tube (CFST) arch bridge was studied in depth, and the research result could offer a reference for near-fault aseismic design.

Symbol recognition system based on 3D stereo vision

2020 ◽  
pp. 1-10
Author(s):  
Linlin Wang
Keyword(s):  
Camera Calibration ◽  
Stereo Vision ◽  
Stereo Matching ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Recognition System ◽  
Symbol Recognition ◽  
Two Dimensional ◽  
Measuring Machine ◽  
Left And Right

With the continuous development of computer science and technology, symbol recognition systems may be converted from two-dimensional space to three-dimensional space. Therefore, this article mainly introduces the symbol recognition system based on 3D stereo vision. The three-dimensional image is taken by the visual coordinate measuring machine in two places on the left and right. Perform binocular stereo matching on the edge of the feature points of the two images. A corner detection algorithm combining SUSAN and Harris is used to detect the left and right camera calibration templates. The two-dimensional coordinate points of the object are determined by the image stereo matching module, and the three-dimensional discrete coordinate points of the object space can be obtained according to the transformation relationship between the image coordinates and the actual object coordinates. Then draw the three-dimensional model of the object through the three-dimensional drawing software. Experimental data shows that the logic resources and memory resources occupied by image preprocessing account for 30.4% and 27.4% of the entire system, respectively. The results show that the system can calibrate the internal and external parameters of the camera. In this way, the camera calibration result will be more accurate and the range will be wider. At the same time, it can effectively make up for the shortcomings of traditional modeling techniques to ensure the measurement accuracy of the detection system.

scholarly journals Cuttlefish use stereopsis to strike at prey

2020 ◽  
Vol 6 (2) ◽  
pp. eaay6036 ◽  
Author(s):  
R. C. Feord ◽  
M. E. Sumner ◽  
S. Pusdekar ◽  
L. Kalra ◽  
P. T. Gonzalez-Bellido ◽  
...  
Keyword(s):  
Information Processing ◽  
Visual Information ◽  
Convergent Evolution ◽  
Visual Fields ◽  
Three Dimensional ◽  
Visual Information Processing ◽  
Depth Information ◽  
Cephalopod Species ◽  
Left And Right

The camera-type eyes of vertebrates and cephalopods exhibit remarkable convergence, but it is currently unknown whether the mechanisms for visual information processing in these brains, which exhibit wildly disparate architecture, are also shared. To investigate stereopsis in a cephalopod species, we affixed “anaglyph” glasses to cuttlefish and used a three-dimensional perception paradigm. We show that (i) cuttlefish have also evolved stereopsis (i.e., the ability to extract depth information from the disparity between left and right visual fields); (ii) when stereopsis information is intact, the time and distance covered before striking at a target are shorter; (iii) stereopsis in cuttlefish works differently to vertebrates, as cuttlefish can extract stereopsis cues from anticorrelated stimuli. These findings demonstrate that although there is convergent evolution in depth computation, cuttlefish stereopsis is likely afforded by a different algorithm than in humans, and not just a different implementation.

Sign in / Sign up

Export Citation Format

Share Document