scholarly journals Fatigue Performance of Different Rib-To-Deck Connections Using Traction Structural Stress Method

2020 ◽  
Vol 10 (4) ◽  
pp. 1239
Author(s):  
Haibo Yang ◽  
Ping Wang ◽  
Hongliang Qian ◽  
Pingsha Dong
Keyword(s):  
Bridge Deck ◽  
Weld Seam ◽  
Numerical Models ◽  
Fatigue Behavior ◽  
Fatigue Performance ◽  
Steel Bridge ◽  
Structural Stress ◽  
Weld Toe ◽  
Weld Root ◽  
And Shifts

The fatigue performance of an orthotropic steel bridge deck is significantly influenced by the type of the rib-to-deck connection considering the crossbeam. Fatigue fracture of the weld seam at the rib-to-deck connection has been a serious problem in such decks. In this paper, numerical models are developed for the orthotropic steel bridge decks and are analyzed for the fatigue behavior. The traction structural stress method is proven to be more accurate and effective in predicting the fatigue life. Fatigue behavior of three typical rib-to-deck connections are obtained by using traction structural stress method and by considering the effect of crossbeams. Compared to the bridge deck with weld seam of a large root, the fatigue performance of the deck with single-sided weld seam is much better with lower equivalent structural stress. The results indicate that the weld seam size should be strictly controlled for better fatigue resistance. The fatigue performance of the bridge deck with double-sided seam is significantly better than that of the bridge deck with single-sided weld seam. An increase in the thickness of the inner weld seam in the rib-to-deck connection optimizes the distribution of the equivalent structural stress and shifts the fatigue failure location from the weld root of the outer weld seam to the weld toe of the inner weld seam thus demonstrating the effect of the crossbeam. The trends of equivalent structural stress with geometric parameters of the weld seam in the rib-to-deck connection are obtained in this study. The fatigue behavior of the components and the equivalent structural stress are significantly influenced by the bridge deck thickness.

scholarly journals Analysis of Fatigue Performance of U-Rib to Deck Connections in Orthotropic Steel Bridge Structures

2020 ◽  
Vol 319 ◽  
pp. 07001
Author(s):  
Haibo Yang ◽  
Ping Wang ◽  
Hongliang Qian
Keyword(s):  
Fatigue Test ◽  
Stress Condition ◽  
Fatigue Behavior ◽  
Fatigue Performance ◽  
Steel Bridge ◽  
Structural Stress ◽  
Test Results ◽  
Analysis Method ◽  
Bridge Structures ◽  
Comparative Results

The stress condition of the transverse rib, bridge deck, and crossbeam in orthotropic steel bridge decks (OSBD) is complicated. Existing fatigue test specimens and the fatigue performance of components in OSBD differ significantly. In this paper, the numerical analysis method using traction structural stress is validated by the comparison with fatigue test results. The evaluation results of the fatigue behavior using the traction structural stress method are proven to be accurate. The comparative results give the fatigue performance of various types of typical test specimens in terms of the equivalent structural stress and initiation locations.

Advanced Local Concepts for Assessing the Fatigue Durability of Welded Joints

2007 ◽  
Vol 348-349 ◽  
pp. 565-568
Author(s):  
C.M. Sonsino ◽  
D. Radaj ◽  
W. Fricke
Keyword(s):  
Fracture Mechanics ◽  
Welded Joints ◽  
Thin Sheet ◽  
Plate Thickness ◽  
Lap Joints ◽  
Structural Stress ◽  
Notch Stress ◽  
Weld Toe ◽  
Mechanics Concepts ◽  
Weld Root

Some recently developed variants of local concepts for assessing the fatigue strength and structural durability of welded joints are reviewed. These comprise structural stress, notch stress or strain and fracture mechanics concepts. New variants of the structural stress concept are Dong’s gradient stress approach and Xiao-Yamada’s ‘one millimetre stress’ approach. FE meshing rules have been developed for welded joints in thin sheet structures. The concept of fictitious notch rounding is now better substantiated for aluminium alloys. The small-size notch concept is applicable to thin sheet lap joints. The new notch stress intensity factor concept is based on the singular stresses at the sharp weld toe notch. Advanced fracture mechanics concepts combine crack initiation at the seam weld root or nugget edge and crack propagation over the plate thickness resulting in endurable FK values as function of cycles per unit thickness, N/t.

Study on Weld Fatigue Evaluation Under Sour Service Environment Using Battelle Structural Stress Method

2013 ◽  
Author(s):  
Jeong K. Hong ◽  
Thomas P. Forte
Keyword(s):  
Fatigue Life ◽  
Fatigue Test ◽  
Fatigue Behavior ◽  
Structural Stress ◽  
Loading Conditions ◽  
Test Results ◽  
Knock Down ◽  
Weld Toe ◽  
Weld Fatigue ◽  
Sour Service

Risers, pipelines and flowlines for deep water applications are subject to corrosive environments. Especially, in the presence of hydrogen sulfide which makes the field sour, their fatigue performance becomes significantly degraded. In order to quantify the sour degradation effect, a knock-down factor has been introduced. This factor is defined as the fatigue life reduction relative to the in-air fatigue life. Several sets of fatigue test results in sour service environments have been published. These include strip specimens of different sizes, e.g., diameters, wall thicknesses, and arc lengths. Naturally, the knock-down factor must be based upon a statistically valid number of fatigue test results obtained from the same specimen geometry and the same loading conditions tested in air and in sour conditions. Currently, the database available in the open literature is too limited to properly define a knock-down factor. Moreover, there is a great deal of scatter within the database and each test in a sour environment is costly and time consuming. Thus, it is difficult to establish a statistically valid database upon which to base the knock-down factor. A mesh-insensitive structural stress method has been developed by Battelle researchers and has been proven to be highly effective in correlating the fatigue behavior of welded joints. In 2007, the Battelle structural stress based weld fatigue master S-N curve was included in ASME Section VIII Div. 2 because it successfully consolidated more than 800 fatigue test results for weld toe failures onto a single master S-N curve with very little scatter, regardless of specimen shape, size, loading type, and steel alloy [1–2]. A knock-down factor is derived by applying the Battelle structural stress method to the existing database for sour environment tests and by using the current in-air database as the reference condition. This approach will reduce the uncertainty in the knock-down factor because it allows a wider range of sour environment data from specimens of different sizes, types, and loading conditions to be combined, while simultaneously reducing scatter. As such, a unified knock-down factor can be determined with greater statistical validity and wider applicability for design recommendations in sour conditions.

scholarly journals Fatigue Property and Improvement of a Rounded Welding Region between the Diaphragm Plate and Closed Rib of an Orthotropic Steel Bridge Deck

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 161 ◽  
Author(s):  
Datao Li ◽  
Chunguo Zhang ◽  
Pengmin Lu
Keyword(s):  
Stress Concentration ◽  
Bridge Deck ◽  
Fatigue Crack Initiation ◽  
Fatigue Property ◽  
Steel Bridge ◽  
Stress Distributions ◽  
Optimization Scheme ◽  
Weld Structure ◽  
Weld Toe ◽  
Orthotropic Steel Bridge Deck

By means of finite element modeling (FEM) and fatigue experiments, we study the fatigue performance of the rounded welding region between the diaphragm plate and closed rib of orthotropic steel bridge deck in this work. A local sub-model of the rounded welding region from the orthotropic steel bridge deck was developed to analyze the stress distributions. Based on the analysis results we designed the fatigue specimen for the fatigue test of this detailed structure. The fatigue experimental results revealed that the crack initiates from the weld toe of the rounded welding region and the stress concentration at the rounded welding region is the main mechanism of fatigue crack initiation. In addition, we propose three improvements to reduce the stress concentration of the rounded welding region, and the local structure optimization scheme of the diaphragm–rib weld can effectively improve the fatigue resistance of the detailed weld structure.

scholarly journals Analysis of fatigue behavior of welded joints in orthotropic bridge deck using traction structural stress

2019 ◽  
Vol 11 (11) ◽  
pp. 168781401989021 ◽  
Author(s):  
Haibo Yang ◽  
Hongliang Qian ◽  
Ping Wang ◽  
Pingsha Dong
Keyword(s):  
Stress Concentration ◽  
Stress Concentration Factor ◽  
Welded Joints ◽  
Concentration Factor ◽  
Hot Spot ◽  
Fatigue Behavior ◽  
Steel Bridge ◽  
Structural Stress ◽  
Test Results ◽  
Hot Spot Stress

In this study, the fatigue behavior of welded joints in an orthotropic steel bridge is simulated and analyzed. The traction structural stress method is proven to be more accurate and effective, and the predicted results agree well with the test results compared to traditional assessment methods, including the nominal stress, hot-spot stress, and effective notch stress methods. The traction structural stress concentration factor curves of welded joints under cyclic tensile and bending moment loading are obtained. The accuracy and validity of finite-element simulation methods for welded joints in orthotropic steel bridge are verified by comparing simulation results with full-scale tests results. Equivalent nominal stresses predicted by the master S–N curve method based on traction structural stress results agree well with the fatigue test results with small standard deviation. The fatigue behavior of orthotropic steel bridge analysis specifications Eurocode3 and GB50017 is combined with the traction structural stress method using unified traction structural stress concentration factor curves. This approach provides practical guidance for the fatigue behavior design of orthotropic steel bridges.

scholarly journals Study on simulation mechanics and fatigue performance of steel bridge deck rigid flexible composite pavement

2021 ◽  
Vol 272 ◽  
pp. 02025
Author(s):  
Yinshan Li ◽  
Linlin Liu ◽  
Tianyu Li ◽  
Ruyong Guo ◽  
Chunying Wu
Keyword(s):  
Bridge Deck ◽  
Asphalt Pavement ◽  
Fatigue Performance ◽  
Steel Bridge ◽  
River Sand ◽  
Box Girder ◽  
Surface Composite ◽  
Steel Box Girder ◽  
Sea Sand ◽  
Pavement Structure

Aiming at the fatigue cracking of steel bridge deck pavement and the shortage of river sand resources, a sea sand RPC pavement scheme was proposed. Taking Quanhe steel box girder bridge as the research background, the simulation model was established by using ANSYS finite element software, and the mechanical simulation analysis of the steel bridge deck sea sand RPC-asphalt pavement composite structure was carried out to determine the most unfavorable load position. A three-point fatigue test was carried out to study the fatigue performance of the structure specimen, and a comparative analysis was made with the river sand RPCasphalt surface composite pavement structure. The results show that the maximum tensile stress and strain of RPC-asphalt pavement appear in the upper middle span of U-shaped stiffener of steel box girder, which are 0.5241MPa and 98.2με, respectively, and the surface of the pavement in this area is prone to crack. The RPC-asphalt surface composite pavement structure has not been damaged after 2 million times of fatigue tests, and has not been damaged after 1 million times of fatigue loading after secondary loading, which indicates that it has better fatigue performance.

scholarly journals Shear Fatigue Performance of Epoxy Resin Waterproof Adhesive Layer on Steel Bridge Deck Pavement

2021 ◽  
Vol 7 ◽  
Author(s):  
Ying Xu ◽  
Xinpeng Lv ◽  
Chunfeng Ma ◽  
Fengming Liang ◽  
Jiafei Qi ◽  
...  
Keyword(s):  
Shear Strength ◽  
Fatigue Life ◽  
Epoxy Resin ◽  
Bridge Deck ◽  
Adhesive Layer ◽  
Fatigue Performance ◽  
Steel Bridge ◽  
Shear Fatigue ◽  
Interlaminar Shear ◽  
Bridge Deck Pavement

In this study, the effects of temperature, shear stress, and coating quantity of waterproof adhesive layer on the shear fatigue performance of a steel bridge deck pavement were investigated. Direct shear fatigue tests of a pavement comprising an epoxy resin waterproof adhesive layer with stone matrix asphalt were conducted at different temperatures, stress levels, and coating quantities. The results show that temperature and stress have significant effects on the shear fatigue life. With increasing temperature and stress, the shear fatigue life of the waterproof adhesive layer decreased gradually. Therefore, for steel bridge deck pavements under high temperatures and heavy loads, the use of asphalt waterproof adhesive layers or pavement layers should be evaluated carefully while limiting the traffic of heavily loaded vehicles. Shear failure occurs at the waterproof adhesive layer–pavement interface and not at the steel–waterproof adhesive layer interface. The shear strength of the epoxy resin waterproof adhesive layer is mainly provided by the bond strength between the waterproof adhesive and pavement mixture as well as the interlocking force between the cured epoxy resin and the bottom interface of uneven pavement mixture. The shear strength increases with the coating quantity of the waterproof adhesive layer; however, after reaching the maximum value, the shear strength becomes stable. In contrast, the interlaminar shear fatigue life increases continuously with the coating quantity of the waterproof adhesive layer. Appropriately increasing the coating quantity is beneficial for improving the resistance of the waterproof adhesive layer to interlaminar shear fatigue failure.

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