Research in Destruction of Concrete Bridge Expanded Joint Influenced by Temperature Difference

2015 ◽  
Vol 744-746 ◽  
pp. 803-806 ◽  
Author(s):  
Xiao Lei ◽  
Yue Yao ◽  
Shi Cao ◽  
Zhi Gang Guo
Keyword(s):  
Temperature Difference ◽  
Curve Fitting ◽  
Effective Temperature ◽  
Joint Damage ◽  
Measured Data ◽  
Concrete Bridge ◽  
Box Girder ◽  
Concrete Box Girder ◽  
Extremum Value ◽  
The Relationship

Destruction of bridge expanded joint is a serious problem for concrete bridge. Based on 5 years measured data, the temperature in the different positions of the concrete box girder was systemically analyzed to illuminate the cause of the bridge expanded joint damage. A method for predicting the extremum value of the temperature difference of concrete girder was proposed by use of the extrema analysis and curve fitting based on the temperature in the different positions of the concrete box girder. The relationship is quite useful in estimating the destruction of bridge expanded joint by effective temperature difference in concrete box-girder.

scholarly journals Modeling of Temperature Time-Lag Effect for Concrete Box-Girder Bridges

2019 ◽  
Vol 9 (16) ◽  
pp. 3255 ◽  
Author(s):  
Kang Yang ◽  
Youliang Ding ◽  
Peng Sun ◽  
Hanwei Zhao ◽  
Fangfang Geng
Keyword(s):  
Phase Difference ◽  
Health Monitoring ◽  
Time Lag ◽  
Thermal Strain ◽  
Temperature Data ◽  
Fourier Series Expansion ◽  
Box Girder ◽  
Lag Effect ◽  
Concrete Box Girder ◽  
The Relationship

It is common to assume the relationship between temperature and temperature response is instantaneous in bridge health monitoring systems. However, a time-lag effect between temperature and thermal strain response has been documented by the analysis of monitored field data of concrete box-girder s. This effect is clearly reflected by the ring feature in the temperature-strain correlation curve. Inevitably, the time-lag effect has an adverse impact on the accuracy and reliability of state assessment and real-time warning for structural health monitoring (SHM) systems. To mitigate the influence of the time-lag effect, a phase-shifting method is proposed based on the Fourier series expansion fitting method. The time-domain signal is firstly converted into the frequency domain signal to compute the phase difference between temperature data and response strain data at each decomposed order. Subsequently, the total phase difference can be obtained by weighted summation. The signal processing effectively reduces the hysteresis loop area and enhances the correlation between the structural response data and the temperature data. When processing the daily data in different seasons, it is found that after subtraction by the proposed method, the linear feature becomes dominant in the relationship between temperature and the strain during long-term observation.

On Sensitivity of Thermal Parameters for Concrete Box Girder in the Sunshine

2008 ◽  
Vol 385-387 ◽  
pp. 825-828 ◽  
Author(s):  
Jian Zhuang Xiao ◽  
Zhi Wen Song ◽  
Chuan Zeng Zhang
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Temperature Field ◽  
Cross Section ◽  
Thermal Effects ◽  
Thermal Parameters ◽  
Concrete Bridge ◽  
The Finite Element Method ◽  
Box Girder ◽  
Concrete Box Girder

In this paper, the temperature field and the thermal effects on a concrete box girder in the sunshine are investigated. For this purpose, the finite element method (FEM) package ANSYS is applied. By varying the values of different thermal parameters, the sensitivity of the thermal parameters is explored. Numerical results are presented and discussed to show the influences of the thermal parameters and the temperature field on the deflection and the tensile stress of a single-span concrete bridge with a box cross section.

scholarly journals Temperature Gradient and Its Effect on Long-Span Prestressed Concrete Box Girder Bridge

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
B. Gu ◽  
F. Y. Zhou ◽  
W. Gao ◽  
F. Z. Xie ◽  
L. H. Lei
Keyword(s):  
Temperature Distribution ◽  
Temperature Gradient ◽  
Prestressed Concrete ◽  
Longitudinal Direction ◽  
Measured Data ◽  
Box Girder ◽  
Long Span ◽  
Concrete Box Girder ◽  
Girder Bridge ◽  
Gradient Models

Temperature variations in the girder at two cross-sections of a long-span prestressed concrete box girder bridge (PCBG) were analysed based on measured data. The results show that the temperature distribution in the concrete box girder (CBG) is strongly influenced by its size, and the temperature distribution in the girder changes along the longitudinal direction of the bridge. To clarify the temperature distribution in the long-span PCBG bridge, a two-dimensional (2D) temperature prediction model, validated by the measured data, was proposed, and the effect of the girder size on the temperature distribution of the CBG was studied using the model. Based on the results of the studies, simplified vertical and transverse temperature gradient models that could consider changes along the longitudinal direction of the bridge were proposed and validated by using the measured data and three-dimensional (3D) mechanical finite element model (FEM) of the bridge. Then, the deformations and stresses derived from the proposed temperature gradient models and the models according to different codes were studied and compared. Finally, conclusions and recommendations for future bridge design are provided.

Crack-based serviceability assessment of post-tensioned segmental concrete box-girder bridges

Structures ◽  
2021 ◽  
Vol 30 ◽  
pp. 1097-1108
Author(s):  
Zhi-Qi He ◽  
Yonghui Li ◽  
Tian Xu ◽  
Zhao Liu ◽  
Zhongguo John Ma
Keyword(s):  
Box Girder Bridges ◽  
Box Girder ◽  
Girder Bridges ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges ◽  
Post Tensioned

Research on CFRP External Pre Stress Reinforcing Vertical Crack of Box Girder Roof

2014 ◽  
Vol 668-669 ◽  
pp. 236-239
Author(s):  
Xin Zhong Wang
Keyword(s):  
Mechanical Properties ◽  
Crack Width ◽  
Longitudinal Crack ◽  
Design Model ◽  
Vertical Crack ◽  
Box Girder ◽  
External Reinforcement ◽  
Reinforcement Efficiency ◽  
Concrete Box Girder ◽  
Reinforcement Model

the article is about longitudinal crack of concrete box girder roof, and it designed a reinforcement model. As the pre stressed material, CFRP could reach 30% of reinforcement efficiency under different loads in design model through external reinforcement upon calculation and analysis. And its crack width greatly reduces. In this way, the reinforcement purpose could be realized, and the mechanical properties of CFRP concrete could be fully played. The effect is obvious.

Sign in / Sign up

Export Citation Format

Share Document