Fatigue assessment of an existing orthotropic steel deck to comply with future traffic intensity

Orthotropic Steel Decks (OSDs) are widely used in long span bridges because of their extremely light weight when compared to their load carrying capacity. These deck types typically consist of a grillage of closed trapezoidal longitudinal stiffeners and transverse web stiffeners, welded to a deck plate. As a result, fatigue problems occur due to the extensive use of complex welded connections. Unfortunately, fatigue effects have often been overlooked during design, which was also the case for an important multiple span box girder viaduct in Belgium (1978).Due to a renovation program of the ring road around Brussels, the number of traffic lanes on the viaduct should be extended from three to four. As a result, questions have been raised about the current structural health of the OSD due to fatigue and future fatigue damage accumulation. Therefore, extensive FEM analyses have been performed, taking into account various parameters such as increased traffic volume and accompanying axle loads, historical positions of the heavy lanes, historical road pavements and their temperature-dependent load spreading effects. In conclusion, accurate fatigue damages have been determined for all fatigue details. Therefore, focused inspections and design solutions can be provided, resulting in a durable bridge management for the next 60 years.

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Analytical and experimental studies on optimal details of orthotropic steel decks for long span bridges

International Journal of Steel Structures ◽

10.1007/s13296-011-2010-6 ◽

2011 ◽

Vol 11 (2) ◽

pp. 227-234 ◽

Cited By ~ 14

Author(s):

Chang-Kook Oh ◽

Kee-Jeung Hong ◽

Doobyong Bae ◽

Heungsub Do ◽

Taejin Han

Keyword(s):

Experimental Studies ◽

Long Span Bridges ◽

Long Span ◽

Orthotropic Steel Decks

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Review on fatigue life assessment methods for welded joints in orthotropic steel decks of long-span bridges

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1201/1/012036 ◽

2021 ◽

Vol 1201 (1) ◽

pp. 012036

Author(s):

B Villoria ◽

S C Siriwardane ◽

H G Lemu

Keyword(s):

Fatigue Life ◽

Residual Stresses ◽

Assessment Methods ◽

Machine Learning Algorithms ◽

Life Assessment ◽

Steel Bridge ◽

Long Span Bridges ◽

Long Span ◽

Fatigue Life Assessment ◽

Orthotropic Steel Decks

Abstract Orthotropic Steel Decks have been used in long-span bridges for several decades because of their high capacity to weight ratio. However, many fatigue related issues have been reported. This paper provides an overview of the main existing fatigue prediction models and discusses their relevance for the fatigue life assessment of Orthotropic Steel Bridge Decks (OSBDs). Several case studies have proven the importance of considering the combined effect of wind and traffic loadings to estimate the fatigue life of long-span bridges. The importance of incorporating welding residual stresses is also well documented while it is often disregarded in design practices. Reliability-based fatigue assessment methods make it possible to quantify how the sources of uncertainty related to loading conditions, welding residual stresses or fabrication defects can affect the fatigue reliability of OSBDs. Monte Carlo simulations are often used to perform probabilistic analyses, but machine-learning algorithms are very promising and computationally efficient. The shortcomings of the Palmgren-Miner rule are discussed and the need for alternative damage accumulation indexes is clear. A number of conclusions are drawn from the analysis of fatigue tests conducted on OSBDs.

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Analysis of the dynamic response of long span bridges with GNSS under typhoon loading

Maritime Technology and Research ◽

10.33175/mtr.2022.254407 ◽

2021 ◽

Vol 4 (3) ◽

pp. Manuscript

Author(s):

Hongbo Wang ◽

Xiaolin Meng ◽

Chaohe Chen

Keyword(s):

Dynamic Response ◽

Real Time ◽

Deformation Monitoring ◽

Bridge Management ◽

Time Data ◽

Engineering Structures ◽

Long Span Bridges ◽

Long Span ◽

Long Span Bridge ◽

Cross Correlation Analysis

Nowadays, real-time bridge deformation monitoring has attracted more attention due to the development of bridge management system and land transportation safety. Huge civil engineering structures, such as long-span bridge, is susceptible to dynamic deflection caused by various loadings. Hence, precise dynamic response measurement becomes necessary to make structure more reliable and integrated. Currently, Global Navigation Satellite System (GNSS) positioning technology has been commonly used in this field to detect the dynamic displacement of long-span bridges. According to this, real-time data were collected from the Forth Road Bridge to observe the dynamic response of lang span bridges under extreme wind load conditions and this report has also verified the data processing technique of the real-time bridge deformation monitoring system. Compared with other monitoring methods, the method used in this report which combines GNSS and anemometer together has features of high frequency with low lag. Moreover, it also shows the superiority of post-processing and synchronization, background noises could be reduced by embedded software. Finally, according to the cross-correlation analysis, it was found that wind speed and bridge displacement in y-axis have the highest correlation. Also, the reliability of combining method to monitor the dynamic response of long-span bridge and noise reducing method proposed in this report has also been verified.

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Experimental study of rib distortion in orthotropic steel decks

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.0704 ◽

2019 ◽

Author(s):

Heng Fang ◽

Nouman Iqbal ◽

Amelie Outtier ◽

Muhammad Kashif ◽

Hans De Backer

Keyword(s):

Stress Concentration ◽

Torsional Rigidity ◽

High Stress ◽

Design Parameters ◽

Long Span Bridges ◽

High Stress Concentration ◽

Long Span ◽

Measurement Results ◽

Positive Correlations ◽

Orthotropic Steel Decks

Longitudinal ribs with the trapezoidal section are broadly adopted in orthotropic steel decks especially for long span bridges. When the tire load is eccentric from the axis of the rib, the torsional rigidity of ribs is critically reduced by distortion which impedes the horizontal dispersal of load. Because of the existence of cutouts in crossbeam, the high stress concentration at the rib-to-crossbeam joint caused by the rib distortion makes the joint easily prone to fatigue damage. In this paper, based on the parametric analysis of several classical design parameters, static load experiments of an orthotropic steel deck specimen are performed. Measurement results support the positive correlations between the weld length of rib-to-crossbeam joint and the distortional stress. The most unfavorable load position of stress concentration induced by rib distortion is also verified, which is about 1600 mm away from the investigated crossbeam. Experimental results indicate that ribs are deformed toward different directions at the midspan section and the crossbeam section separately when the load is eccentric from the axis of rib.

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Design and Mechanical Properties of Steel-UHPC Lightweight Composite Decks

Advances in Civil Engineering ◽

10.1155/2021/8508795 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Yong Liu ◽

Xin Zhang ◽

Rong Liu ◽

Guorong Chen

Keyword(s):

High Capacity ◽

Fatigue Cracking ◽

Economic Benefits ◽

Long Span Bridges ◽

Construction Design ◽

Long Span ◽

Joint Construction ◽

Orthotropic Steel Decks ◽

Pavement Damage ◽

Whole Life Cycle

Orthotropic steel decks (OSDs) have been widely used in long-span bridges due to their advantages of being lightweight, having high capacity, and allowing rapid construction. However, due to the insufficiency of local stiffness of OSD, fatigue cracking and pavement damage have been common problems of OSDs worldwide. It seriously affects the safety and durability of long-span bridges. Therefore, to solve this problem, this paper introduces an innovative steel ultrahigh-performance concrete (steel-UHPC) lightweight composite deck (LWCD). LWCD can reduce the fatigue stress of the conventional OSD by up to 80% and extend the fatigue life to twice the design requirements. Furthermore, engineering practices in China have proven that LWCD can effectively reduce manufacturing costs and maintenance costs throughout the whole life cycle of the structures. Thus, to provide references for design and maintenance of long-span bridges, this paper introduces the structural design, construction techniques, joint construction design, repair methods, and economic benefits of LWCD in detail. Furthermore, numerical simulations and laboratory tests are introduced in this paper to validate the superiority of LWCD.

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