Optimization Study on Open Shaped Ribs Arrangement and Diaphragm Cutout for Steel Orthotropic Box Girder

2012 ◽  
Vol 443-444 ◽  
pp. 1072-1077
Author(s):  
Zhen Wang Wu ◽  
Kai Feng Zheng ◽  
Ying Jie Cui ◽  
Yan Bin Shui
Keyword(s):  
Finite Element ◽  
Parameter Optimization ◽  
Element Model ◽  
Vertical Load ◽  
Box Girder ◽  
Tangential Stresses ◽  
Vehicle Load ◽  
Optimization Study ◽  
Transverse Position ◽  
The Web

The ramp B of one overpass was designed as curved steel orthotropic box girder, whose deck was welded with open shaped bulb ribs in the range of driveways. Then, one detailed finite element model was built to simulate the structure. For the two arrangements of bulb towards and back to web in the cantilever, the tangential stresses of diaphragm cutout were compared under the action of vehicle load. In accordance with above research, it can be concluded that the stress will be more reasonable with the bulb back to web. After altering the transverse position of the vehicle load and calculating the tangential stress along the edge of diaphragm cutout, based on further analysis, it’s generally believed that the following two reasons made the arrangement of bulb back to web more appropriate at least. First of all, the diaphragm connected with the rib adjacent to the web could share part of vertical load. What's more, it could increase the distance from the edge of the cutout to the web center. What come next was to change the diaphragm cutout size, and that parameter optimization was carried out. The results show that a radius of 40-50mm is more applicable for the arc on the bottom of the diaphragm cutout.

scholarly journals Numerical Investigation of Distribution Laws of Shear Force in Box Girder Webs

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Xingwei Xue ◽  
Chao Zang ◽  
Junlong Zhou ◽  
Hai Zhang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Shear Force ◽  
Three Dimensional ◽  
Element Model ◽  
Box Girder ◽  
Comparison Results ◽  
Distribution Laws ◽  
Three Dimensional Finite Element ◽  
The Web

To study the shear force distribution laws of a box girder with a single-box multichamber (SB-MC) configuration for different supporting conditions, numbers of webs, stiffness of end diaphragm, and web thickness values, a box girder with SB-MC was numerically simulated using three-dimensional finite element model. According to the comparison results of web shear force, the concept of η, a shear-increased coefficient for webs, was introduced. The results show that supporting conditions and chambers have a significant impact on the shear-increased coefficient η, and end diaphragm must be set up in the 3D finite element model when calculating η. Nonlinear analysis shows that in the elastic phase, the shear-increased coefficient η basically does not change, but in the cracking stage, the coefficient η of each web changes with the degree of web cracking, and side-webs (S-Webs) reach the ultimate load first. The variation of the web thickness hardly affects the distribution of the shear force, so the method to adjust the web thickness of S-Web was proposed according to the result of shear-increased coefficient η to improve the shear resistance of the box girder.

scholarly journals X-ray nanodiffraction analysis of stress oscillations in a W thin film on through-silicon via

2016 ◽  
Vol 49 (1) ◽  
pp. 182-187 ◽  
Author(s):  
J. Todt ◽  
H. Hammer ◽  
B. Sartory ◽  
M. Burghammer ◽  
J. Kraft ◽  
...  
Keyword(s):  
Thin Film ◽  
Residual Stress ◽  
Finite Element ◽  
Diffraction Data ◽  
Element Model ◽  
Stress Distributions ◽  
Through Silicon Via ◽  
X Ray ◽  
Tangential Stresses ◽  
Stress Components

Synchrotron X-ray nanodiffraction is used to analyse residual stress distributions in a 200 nm-thick W film deposited on the scalloped inner wall of a through-silicon via. The diffraction data are evaluated using a novel dedicated methodology which allows the quantification of axial and tangential stress components under the condition that radial stresses are negligible. The results reveal oscillatory axial stresses in the range of ∼445–885 MPa, with a distribution that correlates well with the scallop wavelength and morphology, as well as nearly constant tangential stresses of ∼800 MPa. The discrepancy with larger stress values obtained from a finite-element model, as well as from a blanket W film, is attributed to the morphology and microstructural nature of the W film in the via.

scholarly journals Comparative Analysis of Static Loading Performance of Rigid and Flexible Road Wheel based on Finite Element Method

2020 ◽  
Vol 70 (1) ◽  
pp. 41-46
Author(s):  
Yaoji Deng ◽  
Youqun Zhao ◽  
Mingmin Zhu ◽  
Zhen Xiao ◽  
Qiuwei Wang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Static Loading ◽  
Maximum Stress ◽  
Three Dimensional ◽  
Element Model ◽  
Vertical Load ◽  
New Type ◽  
Stress And Deformation ◽  
Nonlinear Finite Element Model

To overcome the shortcomings of traditional rigid road wheel, such as poor damping effect and low load-bearing efficiency, a new type of flexible road wheel, having a unique suspension-bearing mode, was introduced. The three-dimensional nonlinear finite element model of rigid and flexible road wheel, considering the triple nonlinear characteristics of geometry, material and contact, is established for numerical investigation of static loading performance. The accuracy of the finite element model of the rigid and flexible road wheel is verified by static loading experiment. The static loading performance of the rigid and flexible road wheels is numerically analyzed. The influence of vertical load on maximum stress and deformation of the rigid and flexible wheels is also studied. The results show that the contact pressure uniformity of the flexible road wheel is better than that of the rigid road wheel under the static vertical load, but the maximum stress and deformation of the flexible road wheel are greater than that of the rigid road wheel. However, this problem can be solved by increasing the number of hinge sets and optimising the joints. The research results provide theoretical basis for replacing rigid road wheel with flexible road wheel, and also provide reference for structural optimisation of flexible road wheel.

A materially nonlinear finite element model for the analysis of curved reinforced concrete box-girder bridges

1993 ◽  
Vol 20 (5) ◽  
pp. 754-759 ◽  
Author(s):  
S. F. Ng ◽  
M. S. Cheung ◽  
J. Q. Zhao
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Finite Element Model ◽  
Element Model ◽  
Nonlinear Material ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Girder Bridges ◽  
Concrete Box Girder ◽  
Concrete Box Girder Bridges

A layered finite element model with material nonlinearity is developed to trace the nonlinear response of horizontally curved reinforced concrete box-girder bridges. Concrete is treated as an orthotropic nonlinear material and reinforcement is modeled as an elastoplastic strain-hardening material. Due to the fact that the flanges and webs of the structure are much different both in configuration and in the state of stresses, two types of facet shell elements, namely, the triangular generalized conforming element and the rectangular nonconforming element, are adopted to model them separately. A numerical example of a multi-cell box-girder bridge is given and the results are compared favourably with the experimental results previously obtained. Key words: finite element method, curved box-girder bridges, reinforced concrete, nonlinear analysis.

scholarly journals Numerical analysis of castellated beams with oval openings

2018 ◽  
Vol 195 ◽  
pp. 02008
Author(s):  
Yanuar Setiawan ◽  
Ay Lie Han ◽  
Buntara Sthenly Gan ◽  
Junaedi Utomo
Keyword(s):  
Finite Element ◽  
Numerical Analysis ◽  
Main Idea ◽  
Element Model ◽  
Steel Beams ◽  
Good Representation ◽  
Actual Behavior ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
The Web

The use of castellated beams has become more popular in the last two decades. The main idea for the use of these types of steel beams is to reduce their self-weight by providing openings in the web of wide flange (WF) or I sections. Numerous research on castellated beams has been conducted, the majority of the studies aimed to optimize the opening size and the shape configuration of the openings. A numerical analysis of castellated beams with oval openings was performed in this study. The sections under investigation had variations in the height-to-length ratios of the beam. The Do to D and b to Do ratios were kept at a constant. The D value was defined as the height of the beam, while Do is the height of the opening, and b is the width of the opening. The numerical analysis was performed by the finite element analysis using the STRAND7 software. The numerical model was further validated to the experimental data. The results showed that the developed finite element model resulted in a very good representation to the actual behavior of the sections.

Calculation of Cross Beam in Continuous Box Girder Bridge Based on Modified Shear Method

2014 ◽  
Vol 578-579 ◽  
pp. 642-647
Author(s):  
Ya Feng Gong ◽  
Xiao Bo Sun ◽  
Huan Li Wang ◽  
Hai Peng Bi
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Traditional Method ◽  
Element Model ◽  
Measured Data ◽  
Box Girder ◽  
Box Girder Bridge ◽  
Girder Bridge ◽  
Simplified Calculation ◽  
The Finite Element Model

The mechanical properties of cross beam in continuous box girder bridge can be obtained through analyzing the finite element model and measured data of bridge. A new simplified calculation method for cross beam is proposed in this paper, which is called modified shear method. Comparative analysis with traditional method is used to verify its feasibility and practicability.

The role of bending stress on the initiation of reverse transverse defects

2020 ◽  
Vol 235 (1) ◽  
pp. 61-72
Author(s):  
Soumyajit Mojumder ◽  
Hang Su ◽  
Cong Qiu ◽  
Peter Mutton ◽  
Aparna Singh ◽  
...  
Keyword(s):  
Finite Element ◽  
Iron Ore ◽  
Maximum Stress ◽  
Load Ratio ◽  
Element Model ◽  
Bending Stress ◽  
Vertical Load ◽  
Lower Head ◽  
Longitudinal Bending

This paper investigated the role of longitudinal reverse bending stress on the initiation of reverse transverse defects. The longitudinal reverse bending stress occurs due to the reverse bending of the rail between two-wheel passage leading to the generation of tensile bending stress at the railhead and the lower head areas. The longitudinal bending stress was investigated as part of a parametric study on the rail cant angle, rail stiffness, lateral-to-vertical load ratio, and rail profile. A finite element model was created by using ABAQUS to analyze the extent of reverse bending in rails with respect to the chosen set of parameters. Under different lateral-to-vertical load ratios of 0, 0.3, 0.5, and 0.7, the maximum stress at the rail lower gauge corner was found to vary between 14.57MPa and 15.47MPa under the reverse bending condition. Similarly, low values of tensile stress under the reverse bending scenario were observed with changes in the rail cant angle and axle spacing with respect to different coal and iron ore wagons. The results revealed that the magnitude of the bending stress under different conditions of reverse bending was not significant enough to initiate a crack at the lower gauge corner.

Positioning of bearings for curved continuous spread-box girder bridges

2002 ◽  
Vol 29 (5) ◽  
pp. 641-652 ◽  
Author(s):  
Magdy Samaan ◽  
Khaled Sennah ◽  
John B Kennedy
Keyword(s):  
Finite Element ◽  
Natural Frequencies ◽  
Structural Response ◽  
Element Model ◽  
Extensive Study ◽  
Mode Shapes ◽  
Box Girder ◽  
Girder Bridges ◽  
Bridge Superstructure ◽  
Girder Bridge

The type and arrangement of bearings for a bridge superstructure are important considerations in bridge design. For a curved continuous spread-box girder bridge, the support conditions for the bridge superstructure may significantly influence the distribution factors for maximum stresses, reactions, and shear forces as well as the bridge natural frequencies and mode shapes. Current design practices in North America recommend very few guidelines for bearing arrangements and types. This paper describes an extensive study carried out using an experimentally calibrated finite element model, in which curved continuous prototype bridges were analyzed to determine their structural response. Six different types and arrangements of support bearings were studied to determine their effect on the maximum stress and reaction distributions as well as on the natural frequencies of such bridges. The results were used to suggest the most favourable bearing arrangement and type.Key words: bridge bearings, composite, continuous, curved bridges, design, distribution factors, finite element, spread-box.

Experimental Determination of the Ultimate Strength of Box Girder Specimens

2016 ◽  
Author(s):  
Thomas Lindemann ◽  
Patrick Kaeding ◽  
Eldor Backhaus
Keyword(s):  
Finite Element ◽  
Experimental Determination ◽  
Ultimate Strength ◽  
Progressive Collapse ◽  
Bending Moment ◽  
Element Model ◽  
Experimental Results ◽  
Bending Test ◽  
Box Girder

The Finite Element Method (FEM) is a feasible tool to perform progressive collapse analyses of large structural systems. Despite enormous developments in finite element formulations and computer technologies the results of structural analyses should be validated against experimental results. In this paper the collapse behaviour of two identical box girder specimens is determined experimentally for the load case of pure longitudinal bending. The specimens are composed of stiffened plate panels and connected at either ends to a loading structure. Within a 4-point bending test a constant bending moment is applied to each specimen to determine the collapse behaviour even in the post-ultimate strength range. The results of the experimental determination of the ultimate strength are presented for the box girder specimens. To simulate the collapse behaviour a finite element model is used and validated against experimental results.

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