scholarly journals Cable-Stayed Bridge Loads Caused by Traffic Congestion on the Deck Measured with Bridge Monitoring System

2021 ◽  
Vol 16 (2) ◽  
pp. 66-89
Author(s):  
Czesław Machelski ◽  
Maciej Hildebrand
Keyword(s):  
Traffic Congestion ◽  
Structural Safety ◽  
Acceptance Test ◽  
Load Testing ◽  
Cable Stayed Bridge ◽  
The Matrix ◽  
Successive Step ◽  
Complex Scheme ◽  
Load Intensity ◽  
Bridge Monitoring System

Structural safety of a bridge depends, among other things, on the number of vehicles passing on its deck, their weights and distribution of loads to their axes. A large number of vehicles can accumulate on the bridge in a controlled state, i.e., during an acceptance test including load testing, and during traffic congestion on the bridge, which is a fortuitous event addressed in this paper. The paper deals with the analysis of load intensity on one bridge carriageway when it is fully and randomly filled during traffic congestion. The influence functions of the forces in the cables are used to determine the effects of loads exerted by the vehicles moving at very low speed. Effects of such loads are studied considering an exemplary cable-stayed bridge. Since the measurement basis was limited, the iterative algorithm was used. It consists in shortening the girder sections under analysis to the area appropriate for determining the load in each successive step of iteration. Ineffectiveness of the traditional algorithm, where the determined system of equations is resolved, is an important premise for using such algorithm. The results of numerical analysis show that the load intensity caused by traffic congestion is relatively high. It has been demonstrated that the matrix method may be successfully used to determine the real load of bridges on the basis of selected parameters measured in the bridge structure, also for complex scheme bridges, including the cable-stayed bridges.

scholarly journals Cable-Stayed Bridge Loads Caused by Traffic Congestion on the Deck Measured with Bridge Monitoring System

2021 ◽  
Vol 16 (2) ◽  
pp. 66-89
Author(s):  
Czesław Machelski ◽  
Maciej Hildebrand
Keyword(s):  
Traffic Congestion ◽  
Structural Safety ◽  
Acceptance Test ◽  
Load Testing ◽  
Cable Stayed Bridge ◽  
The Matrix ◽  
Successive Step ◽  
Complex Scheme ◽  
Load Intensity ◽  
Bridge Monitoring System

Structural safety of a bridge depends, among other things, on the number of vehicles passing on its deck, their weights and distribution of loads to their axes. A large number of vehicles can accumulate on the bridge in a controlled state, i.e., during an acceptance test including load testing, and during traffic congestion on the bridge, which is a fortuitous event addressed in this paper. The paper deals with the analysis of load intensity on one bridge carriageway when it is fully and randomly filled during traffic congestion. The influence functions of the forces in the cables are used to determine the effects of loads exerted by the vehicles moving at very low speed. Effects of such loads are studied considering an exemplary cable-stayed bridge. Since the measurement basis was limited, the iterative algorithm was used. It consists in shortening the girder sections under analysis to the area appropriate for determining the load in each successive step of iteration. Ineffectiveness of the traditional algorithm, where the determined system of equations is resolved, is an important premise for using such algorithm. The results of numerical analysis show that the load intensity caused by traffic congestion is relatively high. It has been demonstrated that the matrix method may be successfully used to determine the real load of bridges on the basis of selected parameters measured in the bridge structure, also for complex scheme bridges, including the cable-stayed bridges.

Innovative Composites with Carbon Nanofillers for Self-Sensing Structural RC Beams

2018 ◽  
Vol 19 ◽  
pp. 12-22 ◽  
Author(s):  
A. D'Alessandro ◽  
A. Meoni ◽  
F. Ubertini
Keyword(s):  
Research Work ◽  
Construction Materials ◽  
Reinforced Concrete Beam ◽  
The Self ◽  
Electrical Performance ◽  
Structural Safety ◽  
Cement Pastes ◽  
The Matrix ◽  
Behavior Modifications ◽  
Carbon Nanofillers

The progress of nanotechnology resulted in the development of new instruments in the civil engineering and its applications. In particular, the use of carbon nanofillers into the matrix of construction materials can provide enhanced properties to the material in both of mechanical and electrical performance. In constructions, concrete is among the most used material. Due to the peculiarities of its components and its structure, it is suitable to modifications, at the nanometer level too. Moreover, to guarantee structural safety it is desirable to achieve a diffuse monitoring of structures in order to identify incipient situations of damages and possible risk for people. The ideal solution would be to realize structures able to identify easily and quickly their behavior modifications. This paper presents a research work about the characterization of the self-sensing abilities of novel cementitious composites with conductive carbon nanoinclusions and their application into a structural reinforced concrete beam. The self-sensing evidence is achieved through the correlation between the variation of strains and the variation of electrical resistance or resistivity. Nanomodified cement pastes with different carbon nanofillers has been tested. The experimental campaign shows the potentialities of this new types of sensors made of nanomodified concrete for diffuse Structural Health Monitoring.

Intelligent Health Monitoring System for a Railway Cable-Stayed Bridge

2010 ◽  
Vol 148-149 ◽  
pp. 1390-1393
Author(s):  
De Shan Shan ◽  
Peng Yan ◽  
Zhen Hua Wang
Keyword(s):  
Information Processing ◽  
Monitoring System ◽  
Health Monitoring ◽  
Signal Transmission ◽  
Structural Safety ◽  
Signal Acquisition ◽  
Processing Technologies ◽  
Health Monitoring System ◽  
Cable Stayed Bridge ◽  
Long Span

Intelligent health monitoring system of the long-span railway cable-stayed bridge requires the comprehensive knowledge of instrumentation, analytical and information processing technologies with the knowledge and experiences in design, construction, operation and maintenance of railway cable-stayed bridge for long-term monitoring the performance throughout its lifecycle. It is necessary to perform sensor-based structural monitoring for identifying the bridge conditions in order to assure the structural safety and to evaluate the operational performance. The considerations for deploying a proper monitoring system are appropriate sensor instrumentation, robust signal acquisition, reliable signal processing, and intelligent signal and information processing. The experience on developing an autonomous monitoring system in the one certain railway cable-stayed bridge newly constructed is introduced in this paper. Sensor and hardware instrumentation, signal transmission, signal acquisition and analysis are schematically described mainly. Experience through this work will be worthwhile lessons for other similar efforts.

Research of Surface Deformation with Metro Double Tunnels Construction and the Relative Position Change

2011 ◽  
Vol 462-463 ◽  
pp. 732-737
Author(s):  
Yan Kai Wu ◽  
Wei Feng
Keyword(s):  
Relative Position ◽  
Traffic Congestion ◽  
Horizontal Plane ◽  
Surface Deformation ◽  
Surface Subsidence ◽  
Structural Safety ◽  
Tunnel Construction ◽  
Position Change ◽  
Construction Sequence ◽  
Tunnel Design

With the rapid development of our economy, the urban traffic becomes increasingly busy. To ease traffic congestion, underground rail transportation is becoming one of the main modes of transportation in city. At present in order to relieve the traffic congestion most major cities in China are accelerating the construction of subway tunnels. The relative position change of metro double tunnels and construction of the sequence will affect the surface subsidence deformation and the interaction of the tunnel lining. It is more concerned about these issues in tunnel design. It is the main purposes, in this paper, to analyze the metro double tunnels surface deformation, which affect by the position changes of new construction double and the sequence of construction. From the numerical simulating results, in order to reduce surface subsidence and ensure the structural safety over the subway tunnel, it should try to make double-tunnels at the same horizontal plane in design. If the double tunnels could not be located at the same horizontal plane, the double-hole tunnel construction sequence of the deformation of the surface subsidence effects are obvious it is obvious that the double tunnels construction sequence differently make the deformation of the surface subsidence. To reduce the deformation of the surface subsidence, it should be first excavated the shallow tunnels and then excavated the tunnel buried deeply. The ideal distance of the double tunnels center is greater than 4 times the tunnel diameter. It can make the surface subsidence reduce to the minimum during the metro tunnel construction.

scholarly journals Evaluation of safety and reliability in an infant reciprocal walking orthosis

2002 ◽  
Vol 26 (2) ◽  
pp. 163-167
Author(s):  
K. Miller ◽  
P. J. Woollam ◽  
N. Jones ◽  
R. Poiner ◽  
I. R. Farmer ◽  
...  
Keyword(s):  
Cyclic Load ◽  
Field Evaluation ◽  
Relative Strength ◽  
The Body ◽  
Structural Testing ◽  
Structural Safety ◽  
Load Testing ◽  
Safety And Reliability ◽  
Lateral Rigidity ◽  
Cyclic Load Testing

In response to new demands for infant walking orthoses consideration was given to the development of a device for this category of patient. A specially developed hip joint with the required structural properties (Woollam et al., 2001) provided an opportunity for this development. Earlier structural assessment, and limited cyclic load testing of key elements of the orthosis (primarily the body brace), confirmed that a safe device for evaluation with patients could, theoretically, be produced. A provisional prototype was therefore designed and manufactured for initial structural testing of the complete infant orthosis (Stallard et al., 2001). Efficiency of walking is strongly influenced by the lateral rigidity of the orthosis. Monitoring the structural performance of the provisional infant design indicated it would equal or improve on the stiffness of that achieved in the adult specification. Additionally, relative strength was comparable with the adult version, which has proven to be safe and reliable in many years of routine prescription. This, together with the limited cyclic testing of the complete orthosis (Stallard et al., 2001), gave confidence that it was safe to proceed with controlled field evaluation of the infant design when supplied as a rehabilitation engineering device within the provisions of an ISO9001 and EN46001 QA System. This additional study of controlled patient use, and further representative cyclic load testing in parallel with the field evaluation, had established the long-term structural safety of the orthosis. Wider application is now to be introduced through completion of the EC (European Community) Medical Devices Directive formalities.

Static and dynamic field load testing of the long span Nissibi cable-stayed bridge

2017 ◽  
Vol 94 ◽  
pp. 136-157 ◽  
Author(s):  
Alemdar Bayraktar ◽  
Temel Türker ◽  
Janusz Tadla ◽  
Altok Kurşun ◽  
Arif Erdiş
Keyword(s):  
Load Testing ◽  
Cable Stayed Bridge ◽  
Long Span ◽  
Dynamic Field

scholarly journals Traffic Speed Forecast in Adjacent Region between Highway and Urban Expressway: Based on MFD and GRU Model

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yuan Gao ◽  
Jiandong Zhao ◽  
Ziyan Qin ◽  
Yingzi Feng ◽  
Zhenzhen Yang ◽  
...  
Keyword(s):  
Traffic Congestion ◽  
Road Traffic ◽  
Temporal Correlation ◽  
Adjacent Region ◽  
Fundamental Diagram ◽  
The Road ◽  
Urban Expressway ◽  
The Matrix ◽  
Traffic Speed ◽  
Traffic Guidance

Traffic congestion in the adjacent region between the highway and urban expressway is becoming more and more serious. This paper proposes a traffic speed forecast method based on the Macroscopic Fundamental Diagram (MFD) and Gated Recurrent Unit (GRU) model to provide the necessary traffic guidance information for travelers in this region. Firstly, considering that the road traffic speed is affected by the macroscopic traffic state, the adjacent region between the highway and expressway is divided into subareas based on the MFD. Secondly, the spatial-temporal correlation coefficient is proposed to measure the correlation between subareas. Then, the matrix of regional traffic speed data is constructed. Thirdly, the matrix is input into the GRU prediction model to get the predicted traffic speed. The proposed algorithm’s prediction performance is verified based on the GPS data collected from the adjacent region between Beijing Highways and Expressway.

scholarly journals Web Performance Testing of Lecturer Evaluation System (e-CEvas) applied with AJAX Technology

2018 ◽  
Vol 3 (3) ◽  
pp. 26-35
Author(s):  
Azmi Abu Seman ◽  
Nor Azlina Mahmud ◽  
Norfiza Ibrahim
Keyword(s):  
Evaluation System ◽  
Architectural Design ◽  
Performance Testing ◽  
Acceptance Testing ◽  
Unit Testing ◽  
Acceptance Test ◽  
Load Testing ◽  
Model Framework ◽  
Web Performance ◽  
Ajax Technology

Lecturer Evaluation System (e-CEvas) is used to measure lecturers’ strength and weaknesses every end of semester by the students. However, the current lecturer evaluation system had many problems such as slow performance, limited interactivity, loss of states and the data transmission had redundant code that was unnecessary in each page. To overcome those stated problem, AJAX technology is used to make the lecturer evaluation system much faster, easier to use, more reliable and increase the performance. This study applied AJAX technology in the development together with Visual Studio Ultimate 2012 as the editor, ASP.NET C# language for coding and SQL Server as the database. V-model framework approach was used in developing this research study which involves requirement analysis, system design, architectural design, module design, unit testing, integration testing, system testing and acceptance testing. Microsoft Visual Studio Web Performance and Load Testing software is used to measure the performance of AJAX technology and the result shows that differences of response time proved that AJAX is powerful web development technique for programming. User Acceptance Test was carried out to measure the satisfaction of users when using e-CEvas which the result shown that most respondents are agree to all instructions in the system and the organization of information on the screens is clear.

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