scholarly journals Historical Beam Bridge Model Identification after Changing its Structural System into an Arch

2016 ◽  
Vol 161 ◽  
pp. 523-529 ◽  
Author(s):  
Grzegorz Poprawa ◽  
Marek Salamak
Keyword(s):  
Model Identification ◽  
Structural System ◽  
Bridge Model ◽  
Beam Bridge

scholarly journals Development of heavy truck models and their effects on girder bridges

2021 ◽  
Author(s):  
Lang Liu ◽  
◽  
Lexian Zhang ◽  
Jie Wang ◽  
Hong Yang ◽  
...  
Keyword(s):  
Bending Moment ◽  
Highway Bridges ◽  
Load Effect ◽  
Girder Bridges ◽  
Heavy Trucks ◽  
Bridge Model ◽  
Potential Factor ◽  
Heavy Truck ◽  
Beam Bridge ◽  
T Beam

The traffic on highway bridges has been increasing in both volume and magnitude, which even has become one of the main reasons leading to damages and collapse of bridges. Most of the existing regulations for overloading checking are carried out based on various limits of gross vehicle weights and axle loads. However, the results of relevant researches show that weight is only a potential factor but not the dominating factor in threatening the safety of bridges. In this study, the concept of load-effect-based heavy truck is proposed for overloading checking, and then three years of WIM data were collected and used to develop heavy truck models for each truck type, based on the understanding of the characteristics and configurations of heavy trucks as well as the distribution of their main parameters. Furthermore, the typical heavy truck models selected and their possible combinations are applied to a simply supported pre-stressed concrete T-beam bridge model with three loading levels, considering one-lane, two-lane and three-lane loaded respectively, then the induced load effect, deflection and stress are discussed for 20 loading cases. The results show the bending moment caused by heavy trucks moving on multiple lanes is 1.6 times the value of the standard truck model in Chinese specification, and the eccentric loading due to a very heavy vehicle moving on single lane usually lead to more severe effect.

Seismic Testing of a Long-Span Concrete Filled Steel Tubular Arch Bridge

2010 ◽  
Vol 456 ◽  
pp. 89-102 ◽  
Author(s):  
Wei Ming Yan ◽  
Yong Li ◽  
Yan Jiang Chen
Keyword(s):  
Dynamic Performance ◽  
Internal Force ◽  
Shaking Table ◽  
Structural System ◽  
Arch Bridge ◽  
Seismic Testing ◽  
Response Characteristics ◽  
Long Span ◽  
Bridge Model ◽  
Cfst Arch Bridge

Long-span bridges are always a multi-support structural system, and seismic ground motion can vary significantly over distances comparable to the length of such kind of bridges, so it’s difficult to carry out shaking table tests because of the restriction of the dimension and amount of shaking tables. This paper discusses the multiple sub-table cordwood system is used to conduct a study on the seismic testing of a three-span irregular Concrete filled steel tubular (CFST) arch bridge with the objective of investigating the dynamic performance of the bridge under spatial earthquake motions. The development and testing of the bridge model and selected experimental results are discussed then. The seismic response and response characteristics of acceleration, displacement, internal force, and strain of the structure under earthquake excitations are gained, which can provide test data and basis to evaluate the seismic performance of this CFST arch bridge or other similar structural system design.

scholarly journals Experimental Estimating Deflection of a Simple Beam Bridge Model Using Grating Eddy Current Sensors

Sensors ◽  
2012 ◽  
Vol 12 (8) ◽  
pp. 9987-10000 ◽  
Author(s):  
Chunfeng Lü ◽  
Weiwen Liu ◽  
Yongjie Zhang ◽  
Hui Zhao
Keyword(s):  
Eddy Current ◽  
Bridge Model ◽  
Current Sensors ◽  
Beam Bridge

Frequency modification of continuous beam bridge based on co-integration analysis considering the effect of temperature and humidity

2018 ◽  
Vol 18 (2) ◽  
pp. 376-389 ◽  
Author(s):  
Haoxiang He ◽  
Wei Wang ◽  
Xiaofu Zhang
Keyword(s):  
Environmental Factors ◽  
Effect Of Temperature ◽  
Integration Theory ◽  
Frequency Model ◽  
Modified Method ◽  
Continuous Beam Bridge ◽  
Bridge Model ◽  
Temperature And Humidity ◽  
Beam Bridge ◽  
Integration Analysis

The variation of the temperature and humidity significantly affects the modal parameters of the structure, and the effect and the quantitative statistics of single environmental factors such as temperature on the frequency of bridge are intensively studied, but the study on the mechanism and the effective model considering the comprehensive effect of multi-environmental factors is relatively rare. The principle and analysis method of co-integration is introduced, and the frequency-modified method based on co-integration is presented. Through the monitoring of a three-span concrete bridge model in the natural environment, the effective monitoring data are analyzed to establish a long-term equilibrium model about “frequency–temperature–humidity” based on co-integration theory. The experimental results indicate that the model has a better fitting ability and accuracy, and it is can be used to predict the variation trend of frequency. Based on the mathematical model of co-integration analysis, the modified frequency model considering multi-environmental factors is proposed, which can eliminate the comprehensive effect of temperature and humidity on frequency, and the variation of dynamic characteristics due to the internal causes of structure is revealed. The extracted sequence can provide effective information for further safety assessment and damage detection of bridge.

Experimental Study on the Effect of Temperature on Modal Frequencies of Bridges

2018 ◽  
Vol 18 (12) ◽  
pp. 1850155 ◽  
Author(s):  
Limin Sun ◽  
Yi Zhou ◽  
Zhihua Min
Keyword(s):  
Boundary Conditions ◽  
Freezing Point ◽  
Concrete Bridges ◽  
Effect Of Temperature ◽  
Steel Cable ◽  
Temperature Changes ◽  
Continuous Beam Bridge ◽  
Bridge Model ◽  
Increasing Temperature ◽  
Beam Bridge

This study investigates the relationship between the temperature and the modal frequencies of bridges through a series of model experiments using a concrete continuous beam bridge model and a steel cable-stayed bridge model in a controlled-temperature chamber. The experimental results show that, for a given boundary condition and in the absence of freezing, a change in temperature affects the structural frequencies of the bridge as it alters the elastic modulus of the bridge materials. The structural frequency tends to linearly decrease with increasing temperature and with the decrease in the frequency of steel bridges smaller than that of concrete bridges. For the particular case of wet concrete bridges, the temperature dependencies of modal frequencies vary dramatically near the freezing point, which is attributable to the freeze–thaw process of concrete pore water. The effect of air humidity on structural frequency is less significant than that of temperature when the boundary conditions remain unchanged. Furthermore, temperature changes may alter the boundary conditions of bridges, thereby affecting the structural frequencies.

The Study of Diaphragm Beam Influence to Load Transverse Distribution of T-Beam Bridge

2011 ◽  
Vol 368-373 ◽  
pp. 557-562
Author(s):  
Guo Hui Gao ◽  
Zhen Yu Xie ◽  
Ran He ◽  
Jian Yi Song
Keyword(s):  
Theoretical Data ◽  
Mechanical Analysis ◽  
Concentrated Load ◽  
Transverse Distribution ◽  
Finite Element Software ◽  
Bridge Model ◽  
Diaphragm Beam ◽  
Beam Bridge ◽  
Bridge Models ◽  
T Beam

Diaphragm beam has grate influence to load transverse distribution factors of T-beam bridge. Two steel T-beam bridge models were made in this article, one have diaphragm beam and the other one have not. Concentrated load was applied to both of them, and mechanical analysis of the T-beam bridge model was carried out by finite element software. Compared with experiment data and theoretical data, it shows that: when the concentrated load was applied to mid-span of 1#,2# and 3# beam of the two kind bridges, the 1#,2# and 3# beam load transverse distribution factors of T-beam bridge without diaphragm beam is larger than that of T-beam bridge with diaphragm beam by 19.3%~23.2%、25.3%~30.6% and 48.1%~50.1% respectively.

Towards an efficient method of predicting vehicle-induced response of bridge

2016 ◽  
Vol 33 (7) ◽  
pp. 2067-2089 ◽  
Author(s):  
Zhen Sun ◽  
Zilong Zou
Keyword(s):  
Iterative Method ◽  
Design Methodology ◽  
Computational Algorithm ◽  
Interaction Force ◽  
Induced Response ◽  
Vehicle Model ◽  
Content Type ◽  
Bridge Model ◽  
Beam Bridge ◽  
Bridge Models

Purpose The purpose of this paper is to present a practical and efficient iterative method for predicting vehicle-induced response of bridge. Design/methodology/approach The vehicle-bridge interaction (VBI) problem is generalized mathematically and a computational algorithm for VBI is proposed. This method rests on an iterative procedure, which utilizes the whole interaction process for iteration. By this means, vehicle and bridge become totally uncoupled and are only linked by the contact force history. This method provides flexibility to choose simplified or refined vehicle and bridge models for the VBI problem, as well as open options for different commercial FEM software without specialized codes. Findings The method is verified through two numerical examples. The first example uses a simple 1D beam bridge model, which illustrates the procedure of this method and demonstrates its fast convergence in several iterations. The second example employs a realistic full 3D finite element bridge model, which shows that the method easily connects complex FEM bridge models in ABAQUS with a calibrated vehicle model in Matlab. The dynamic response of the bridge is reliably calculated within only a few iterations. Originality/value The proposed iterative method separates vehicle and bridge into independent subsystems in the computational process, thus providing more flexibility to utilize commercial FEM softwares. Its efficiency is realized through choosing the whole interaction force process for iteration, which considerably reduces the iteration steps.

Bridge condition monitoring under moving loads using two sensor measurements

2019 ◽  
Vol 19 (3) ◽  
pp. 917-937 ◽  
Author(s):  
Zhenhua Nie ◽  
Jun Lin ◽  
Jun Li ◽  
Hong Hao ◽  
Hongwei Ma
Keyword(s):  
Damage Detection ◽  
Structural Damage ◽  
Damage Index ◽  
Structural Vibration ◽  
Measurement Information ◽  
Moving Mass ◽  
Moving Vehicle ◽  
Bridge Model ◽  
Vibration Responses ◽  
Beam Bridge

A novel damage detection approach using only two sensors to detect the damage in beam bridges subjected to a moving vehicle is proposed in this article. In this approach, a moving mass is considered representing a vehicle moving across the bridge, and structural vibration responses at two locations are measured from a pair of sensors. A moving window is defined with a certain length determined by the sampling frequency and the fundamental frequency of the measured responses. The windowed pair time series extracted from these two measured responses are used to calculate the cross-correlation, which is used to define the local damage index. A simply supported beam bridge subjected to a moving mass is simulated to demonstrate the effectiveness and accuracy of the proposed approach. Numerical results indicate that the proposed approach can accurately identify the single and multiple damages using both displacement and acceleration responses, even when the responses are smeared with a significant noise. This indicates a good robustness to the noise effect. Experimental verifications on a laboratory beam bridge model demonstrate that the proposed approach can successfully identify the damage location using different selections of sensor pairs. Both the numerical and experimental results demonstrate that the new damage index is a good candidate for structural damage detection with very limited measurement information.

Structural robustness of long-span cable-supported bridges segmented by zipper-stoppers to prevent progressive collapse

2018 ◽  
Author(s):  
Mohammad Shoghijavan ◽  
Uwe Starossek
Keyword(s):  
Analytical Approach ◽  
Good Accuracy ◽  
Numerical Models ◽  
Progressive Collapse ◽  
Structural System ◽  
Structural Behaviour ◽  
Load Bearing Capacity ◽  
Approximation Function ◽  
Long Span ◽  
Bridge Model

<p>This paper investigates the structural behaviour of a long-span cable-supported bridge segmented by zipper-stoppers after the sudden rupture of some of its cables. Increasing the robustness of the structural system through segmentation is a possible approach to prevent progressive collapse in bridges due to cable failure. In this concept, zipper-stoppers, at the segment borders, are strong components with the multiple of the load bearing capacity of usual members and are designed to arrest a zipper-like collapse in the segment where the initial damage occurred. For finding the “stress increase ratio” of the zipper-stopper, an analytical approach based on differential equations of the system will be used. Then, an approximation function for a simplified bridge model in a cable-loss scenario will be derived. The proposed approximation function has been checked by numerical models, and its good accuracy has been proven.</p>

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