Experiment Study of Chaos Motion of Cable-Stayed

2013 ◽  
Vol 444-445 ◽  
pp. 748-752
Author(s):  
Jin Hai Li
Keyword(s):  
Time History ◽  
Traffic Load ◽  
Acceleration Sensor ◽  
Cable Model ◽  
Smale Horseshoe ◽  
Acceleration Data ◽  
Set Up ◽  
Chaos Motion ◽  
Cable Damage ◽  
Cable Stayed Bridges

The cable-stayed is one of the principal force members of cable-stayed bridges. It would be prone to exhibit vibration of large amplitude on the action of wind, earthquake and traffic load,so it reduces the life of stayed cable and even cause destruction. In order to reduce the cable damage, it is very necessary to study the mechanism of vibration of cable-stayed. Experiments are conducted to explore the nonlinear vibration of cable under the periodic external force. A cable model with 14.3 meters long is set up and an acceleration sensor is installed on the midpoint of cable. Time-history acceleration data are obtained by using of acceleration sensor under three cycle load. From the data a Poincare Map is provided and chaos motion is confirmed by using of Smale Horseshoe Map theory.

Measuring heavy traffic with WIM-ROAD and WIM-BRIDGE systems in an urban environment

2021 ◽  
Author(s):  
Maarten Soudijn ◽  
Sebastiaan van Rossum ◽  
Ane de Boer
Keyword(s):  
Heavy Traffic ◽  
Pressure Sensors ◽  
Strain Sensors ◽  
Traffic Load ◽  
Structural Safety ◽  
Special Focus ◽  
The Road ◽  
Weigh In Motion ◽  
Set Up ◽  
Calibration Program

<p>In this paper we present weight measurements of urban heavy traffic comparing two different Weigh In Motion (WIM) systems. One is a WIM-ROAD system using Lineas quartz pressure sensors in the road surface. The other is a WIM-BRIDGE system using optical fibre-based strain sensors which are applied under the bridge to the bottom fibre of a single span of the bridge deck. We have designed our tests to determine which system is most suited to Amsterdam. We put special focus on the accuracy that each system can achieve and have set up an extensive calibration program to determine this. Our ultimate goal is to draw up a realistic traffic load model for Amsterdam. This model would lead to a recommendation that can be used to re- examine the structural safety of existing historic bridges and quay walls, in addition to the current traffic load recommendations.</p>

Automatical Emotion Recognition Based on Daily Gait

2019 ◽  
pp. 61-74
Author(s):  
Xiaoqian Liu ◽  
Tingshao Zhu
Keyword(s):  
Mental Health ◽  
Emotion Recognition ◽  
Health Monitoring ◽  
Wearable Devices ◽  
Psychology Research ◽  
Acceleration Sensor ◽  
Emotion Identification ◽  
Technology Application ◽  
Sensing Technology ◽  
Acceleration Data

In this chapter, a kind of emotion recognition method based on gait using a customized smart bracelet with a built-in acceleration sensor was introduced in detail. The results showed that the classification accuracies of angry-neutral, happy-neutral, angry-happy, and angry-happy-neutral using the acceleration data of wrist are 91.3%, 88.5%, 88.5%, and 81.2%, respectively. Besides, the wearable devices and motion-sensing technology application in psychology research have been further discussed, and non-contact emotion identification and mental health monitoring based on offline behaviors were reviewed summarily.

Research on Methods for Elastic Stiffness of Multi-Ribbed Slab Structure

2010 ◽  
Vol 97-101 ◽  
pp. 1736-1740
Author(s):  
Qi Zhang ◽  
Dong Bo Li ◽  
Qian Feng Yao ◽  
Dong Zhao
Keyword(s):  
Time History ◽  
Elastic Stiffness ◽  
Structural Effect ◽  
Time History Analysis ◽  
Equivalent Model ◽  
Test Results ◽  
History Analysis ◽  
Set Up

Considering the influence of the flange and rib column, the equivalent model of multi-ribbed slab is set up by the theory based on the strengthening isotropism fiber. This model is simple, highly precise and strongly applicable through comparing analyzing results with test results. Besides, the calculated formulate is set up on the basis of the whole structural effect and space work, which offers the prerequisite for elastic time history analysis of the structure.

Frequency-Domain Estimation Method for Vibration-Induced Additional Cable Tension Based on Acceleration Monitoring

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Bin Xu ◽  
Danhui Dan ◽  
Yiming Zhao
Keyword(s):  
Frequency Domain ◽  
Dynamic Stiffness ◽  
Estimation Method ◽  
Dynamic Environment ◽  
Parameter Analysis ◽  
Traffic Load ◽  
Cable Tension ◽  
Measuring Point ◽  
Cable Vibration ◽  
Acceleration Data

Abstract Under excitation due to the environment or traffic load, cable vibration never ceases; thus, fatigue cycles generated by vibration-induced additional cable tension (VACT) owing to the change of the cable configuration from static to dynamic are significantly frequent. Therefore, VACT is a non-negligible cable-fatigue load. To investigate the cable dynamic stability and fatigue, it is necessary to determine VACT in a dynamic environment. Herein, a method for estimating VACT in the frequency-domain by using acceleration data is proposed. In this method, according to the cable vibration control equation, the frequency-domain relationship between the VACT and the vibration response of the measuring point is established based on the dynamic stiffness. Parameter analysis simplifies the proposed model to estimate VACT using only acceleration data. The proposed method is verified with cable acceleration data.

Dynamic Response Characteristics of Underground Powerhouse Caverns for Sandaowan Hydropower Station

2011 ◽  
Vol 382 ◽  
pp. 80-83 ◽  
Author(s):  
Zhen Zhong Shen ◽  
Hua Chun Ren
Keyword(s):  
Seismic Waves ◽  
Low Frequency ◽  
Time History ◽  
Element Model ◽  
Frequency Characteristics ◽  
Dynamic Responses ◽  
Principal Stresses ◽  
Underground Powerhouse ◽  
Response Characteristics ◽  
Set Up

According to the practical situation, the 3-D finite element model of Sandaowan underground powerhouse caverns on Taolai River is set up for analyzing the behaviors under earthquake action. Based on static stress field of the surrounding rock mass, and with the selection of appropriate seismic waves for dynamic time-history analysis method, the dynamic responses of underground powerhouse caverns are analyzed. It is shown that the time-history waveform of dynamic displacement of given points has a very similar variation regularity with that of acceleration, and the wave phases of both are almost synchronous. The dynamic displacements and principal stresses of the given points on rock walls are with the vibration of low-frequency characteristics, the acceleration response is with the vibration of high-frequency characteristics.

scholarly journals Use of Acceleration Sensors in Archery

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 98
Author(s):  
Markus Eckelt ◽  
Franziska Mally ◽  
Angelika Brunner
Keyword(s):  
Range Of Motion ◽  
Video Analysis ◽  
Coefficient Of Variation ◽  
Three Dimensional ◽  
Feedback System ◽  
Complex Data ◽  
Acceleration Sensor ◽  
Acceleration Sensors ◽  
Motion Sequence ◽  
Set Up

Archery is a quasi-static sport. Nevertheless, it requires maximum concentration, as well as precision from the archer. Previous research used combinations of several sensors, video analysis and electromyography to analyse the motion sequence and to identify parameters leading to a worse score. Therefore, the aim of this study is to verify if solely an acceleration sensor on the archer’s hand, without complex data processing, could be used to set up a feedback system. For testing, six participants with a three dimensional acceleration sensor on each hand shot indoors at a vertical triple target. The parameters analysed were the duration of the movement, the range of motion and the coefficient of variation. The results indicate that the analysis of the coefficient of variation shows no correlation with the score reached, whereas the analysis of the duration and the range of motion does.

scholarly journals Numerical Analysis-Based Blast Resistance Performance Assessment of Cable-Stayed Bridge Components Subjected to Blast Loads

2020 ◽  
Vol 10 (23) ◽  
pp. 8511
Author(s):  
Jungwhee Lee ◽  
Keunki Choi ◽  
Chulhun Chung
Keyword(s):  
Numerical Analysis ◽  
Blast Resistance ◽  
Assessment Process ◽  
Public Nature ◽  
Bridge Structures ◽  
Set Up ◽  
Existing Bridges ◽  
Resistance Performance ◽  
Selection Of ◽  
Cable Stayed Bridges

Cable-stayed bridges are infrastructure facilities of a highly public nature; therefore, it is essential to ensure operational safety and prompt response in the event of a collapse or damage, which are caused by natural and social disasters. Among social disasters, blast accidents can occur in cable-stayed bridges as a result of explosions produced by vehicle collisions or terrorist attacks; this can lead to the degradation in their structural performances and subsequent collapse. In this research, a procedure to assess structural blast-resistance performance is suggested based on a numerical analysis approach, and the feasibility of the procedure is demonstrated by performing an example assessment. The suggested procedure includes (1) selection of major structural components that severely affect the global structural behavior, (2) set-up blast hazard scenarios consisting of various blast levels and locations, and (3) assessment of the components using numerical blast simulation. By performing an example assessment, the critical blast level for each component could be determined and the blast location that affects the considering components the most severely could be found as well. The scenario-based assessment process employed in this study is expected to facilitate the evaluation of bridge structures under blasts in both existing bridges and future designs.

Non-Linear Analysis of Cable Stayed Bridges

2018 ◽  
Vol 6 (9) ◽  
pp. 36
Author(s):  
Zuber Ahmed ◽  
Esar Ahmed
Keyword(s):  
Response Spectrum ◽  
Research Work ◽  
Structural Response ◽  
Time History ◽  
Mode Shapes ◽  
Span Length ◽  
Ground Acceleration ◽  
Axial Forces ◽  
Aesthetic Appearance ◽  
Cable Stayed Bridges

The concept of cable-stayed bridges dates back to the seventeenth century. Due to their aesthetic appearance, efficient utilization of material, and availability of new construction technologies, cable-stayed bridges have gained much popularity in the last few decades. After successful construction of the Sutong Bridge, a number of bridges of this type have been proposed and are under construction, which calls for extensive research work in this field. Nowadays, very long span cable-stayed bridges are being built and the ambition is to further increase the span length using shallower and slender girders. In order to achieve this, accurate procedures need to be developed which can lead to a thorough understanding and a realistic prediction of the bridge’s structural response under different load conditions.In the present study, an attempt has been made to analyze the seismic response of cable stayed bridges with single pylon and two equal side spans. This study has made an effort to analyze the effect of both static and dynamic loadings on cable-stayed bridges and corresponding response of the bridge with variations in span length, pylon height and pylon shape. Comparison of static analysis results have been made for different configuration of bridges - their mode shapes, time period, frequency, pylon top deflection, maximum deck deflection; and longitudinal reaction, lateral reaction and longitudinal moment at pylon bottom. Time history analysis results have been investigated for different configuration of bridges under the effects of three earthquakes response spectrum (Bhuj, El Centro and Uttarkashi) - axial forces in stay cables, deck deflections and stress diagrams at maximum peak ground acceleration of the above mentioned earthquakes.

Bridge Surface Roughness Detection Based on Double-Vehicle-Double-Pass Technique

2018 ◽  
Author(s):  
Ying Zhan
Keyword(s):  
Surface Roughness ◽  
Measured Data ◽  
Traffic Load ◽  
Double Pass ◽  
Bridge Monitoring ◽  
Roughness Profile ◽  
Element Simulation ◽  
Acceleration Data ◽  
Tire Wear ◽  
Wear And Tear

Bridge surface roughness encompasses dents, cracks, bulges and other defects due to construction as well as wear and tear in service. It significantly affects the traffic load on bridge, costs extra vehicle fuel consumption and tire wear, and therefore is a major concern of bridge monitoring and maintenance. As it considerably affects the contact force between the vehicle and the bridge, it is also a major obstacle of using vehicle measured data to identify bridge parameters. This paper presents a method to estimate the surface roughness profile of a bridge. With the acceleration data gathered from two different vehicles running on the bridge successively at the same speed, the roughness profile of the bridge can be measured with satisfactory accuracy. The method is verified with finite element simulation.

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