Modeling Elastic Stability of a Pressed Box Girder Flange

2013 ◽  
Vol 343 ◽  
pp. 35-41 ◽  
Author(s):  
Mirko Djelosevic ◽  
Ilija Tanackov ◽  
Milan Kostelac ◽  
Vladeta Gajic ◽  
Jovan Tepic
Keyword(s):  
Elastic Stability ◽  
Deformation Energy ◽  
Box Girders ◽  
Cross Sectional ◽  
Box Girder ◽  
Local Loads ◽  
Combined Loads ◽  
Minimum Deformation ◽  
Elastically Restrained Edges ◽  
Elastically Restrained

The paper examines the elastic stability of pressed sheet metal flange of a box girder. Mathematical interpretation of elastic stability is performed on the model plate with two freely supported and two elastically restrained edges subjected to combined loads. The research is based on the energy analysis approach, using the principle of minimum deformation energy and the method of cross-sectional girder element decomposition. The plate elastic stability mechanism is investigated in an interactive environment that simulates local loads and compressive longitudinal forces produced by global stress. The significant geometric parameters, as well as support and load conditions affecting the loss of stability, are identified. The research results can be applied as a constraint on the local flange stability in the optimization of box girders.

scholarly journals An Exact Series Solution for the Vibration of Mindlin Rectangular Plates with Elastically Restrained Edges

2014 ◽  
Vol 2014 ◽  
pp. 1-11
Author(s):  
Xue Kai ◽  
Wang Jiufa ◽  
Li Qiuhong ◽  
Wang Weiyuan ◽  
Wang Ping
Keyword(s):  
Boundary Conditions ◽  
Plate Theory ◽  
Mindlin Plate ◽  
Rectangular Plates ◽  
Cross Sectional ◽  
Fourier Cosine ◽  
Cosine Series ◽  
The Matrix ◽  
Elastically Restrained Edges ◽  
Elastically Restrained

An analysis method is proposed for the vibration analysis of the Mindlin rectangular plates with general elastically restrained edges, in which the vibration displacements and the cross-sectional rotations of the mid-plane are expressed as the linear combination of a double Fourier cosine series and four one-dimensional Fourier series. The use of these supplementary functions is to solve the possible discontinuities with first derivatives at each edge. So this method can be applied to get the exact solution for vibration of plates with general elastic boundary conditions. The matrix eigenvalue equation which is equivalent to governing differential equations of the plate can be derived through using the boundary conditions and the governing equations based on Mindlin plate theory. The natural frequencies can be got through solving the matrix equation. Finally the numerical results are presented to validate the accuracy of the method.

Design of horizontally curved composite box-girder bridges: a simplified approach

1995 ◽  
Vol 22 (1) ◽  
pp. 93-105 ◽  
Author(s):  
M. S. Cheung ◽  
S. H. C. Foo
Keyword(s):  
Radius Of Curvature ◽  
Curved Bridges ◽  
Box Girders ◽  
Box Girder Bridges ◽  
Cross Sectional ◽  
Box Girder ◽  
Horizontally Curved ◽  
Finite Strip ◽  
Girder Bridges ◽  
Bridge Models

Because of their excellent torsional capacity, box girders are used extensively in modern bridge construction having curved alignments. Applications of most design codes have been limited to bridges where the radius of curvature is much greater than the span length and cross-sectional dimensions. To meet the practical requirements arising during the design process, simple design methods are needed for curved bridges. This paper presents the results of a parametric study on the relative behaviour of curved and straight box-girder bridges and on the development of a simplified design method for the combined longitudinal moment of curved bridges. The combined moment includes the effects of flexure, torsion, and distortion. Three simply supported concrete-steel composite bridge models, including single-cell, twin-cell, and three-cell box girders and subjected to loadings as specified in the Ontario Highway Bridge Design Code, were analyzed using the finite strip method. The parameters considered in the study include types of cross section; types, locations, and magnitudes of loads; span lengths; and radius of curvature. Preliminary analysis of the results suggests that the behaviour of horizontally curved box-girder bridges is dependent on a variety of parameters, but most importantly on the span-to-radius ratio. Empirical relationships for combined longitudinal moment between curved and straight box-girder bridges are also proposed. Key words: bridge, curved, composite, design, finite strip.

An Exact Series Solution for the Vibration of Mindlin Rectangular Plates with Elastically Restrained Edges

2013 ◽  
Vol 572 ◽  
pp. 489-493 ◽  
Author(s):  
Kai Xue ◽  
Jiu Fa Wang ◽  
Qiu Hong Li ◽  
Wei Yuan Wang ◽  
Ping Wang
Keyword(s):  
Series Solution ◽  
Rectangular Plates ◽  
Analysis Method ◽  
Original Function ◽  
Cross Sectional ◽  
Fourier Cosine ◽  
Cosine Series ◽  
Fourier Cosine Series ◽  
Elastically Restrained Edges ◽  
Elastically Restrained

An analysis method has been proposed for the vibration analysis of the Mindlin rectangular plates with general elastically boundary supports, in which the vibration displacements and the cross-sectional rotations of the mid-plane are sought as the linear combination of a double Fourier cosine series and auxiliary series functions. The use of these supplementary functions is to solve the potential discontinuity associated with the x-derivative and y-derivative of the original function along the four edges, so this method can be applied to get the exact solution. Finally the numerical results are presented to validate the correct of the method.

scholarly journals Unconventional Bearing Capacity Analysis and Optimization of Multicell Box Girders

2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
Jovan Tepic ◽  
Rade Doroslovacki ◽  
Mirko Djelosevic
Keyword(s):  
Bearing Capacity ◽  
Specific Capacity ◽  
Strain Analysis ◽  
Local Stress ◽  
Constant Load ◽  
Maximum Deviation ◽  
Capacity Analysis ◽  
Box Girders ◽  
Cross Sectional ◽  
Box Girder

This study deals with unconventional bearing capacity analysis and the procedure of optimizing a two-cell box girder. The generalized model which enables the local stress-strain analysis of multicell girders was developed based on the principle of cross-sectional decomposition. The applied methodology is verified using the experimental data (Djelosevic et al., 2012) for traditionally formed box girders. The qualitative and quantitative evaluation of results obtained for the two-cell box girder is realized based on comparative analysis using the finite element method (FEM) and the ANSYS v12 software. The deflection function obtained by analytical and numerical methods was found consistent provided that the maximum deviation does not exceed 4%. Multicell box girders are rationally designed support structures characterized by much lower susceptibility of their cross-sectional elements to buckling and higher specific capacity than traditionally formed box girders. The developed local stress model is applied for optimizing the cross section of a two-cell box carrier. The author points to the advantages of implementing the model of local stresses in the optimization process and concludes that the technological reserve of bearing capacity amounts to 20% at the same girder weight and constant load conditions.

Parametric Study of Single Cell Box Girder Bridge under Different Radii of Curvature

2016 ◽  
Vol 857 ◽  
pp. 165-170
Author(s):  
Jefeena Sali ◽  
Regi P. Mohan
Keyword(s):  
Parametric Study ◽  
Torsional Rigidity ◽  
Radius Of Curvature ◽  
Dead Load ◽  
Box Girders ◽  
Box Girder Bridges ◽  
Cross Sectional ◽  
Box Girder ◽  
Girder Bridges ◽  
Girder Bridge

Box girders are now prominently used in freeway and bridge systems because of its structural efficiency, better stability, serviceability, economy of construction and pleasing aesthetics. Due to its high torsional rigidity box girders are most suited for curved bridges. In the present investigation, a comparative study of straight and curved box girder bridges with trapezoidal cross section has been carried out. The analysis is carried under the dead load, super imposed dead load, live load of IRC Class A tracked vehicle and prestressed load .This paper focus on the parametric study of box girders with different radius of curvature by keeping the span, cross sectional shape and material properties constant. The parametric investigations performed on curved box girders helps to evaluate the effects of change in radius of curvature on the behaviour of the box girders. This study would help the bridge engineers to better understand the behaviour of straight and curved box girder bridges. The results obtained from this study will be a valuable guidance to the bridge designers.

Influence of Antisymmetrical Actions at Reinforced Concrete Cable-Stayed Bridge

2017 ◽  
Vol 738 ◽  
pp. 3-14 ◽  
Author(s):  
Ivan Balaz ◽  
Yvona Kolekova ◽  
Michal Kovac ◽  
Ivana Veghova
Keyword(s):  
Czech Republic ◽  
Reinforced Concrete ◽  
Beam Theory ◽  
Box Girders ◽  
Cross Sectional ◽  
Box Girder ◽  
Cable Stayed Bridge ◽  
Internal Forces ◽  
Theory Calculation ◽  
Generalized Beam Theory

Calculation of the cross-sectional properties of the concrete box-girder with two-cells using Vlasov`s theory and Generalized Beam Theory. Calculation of the internal forces of the St. Venant torsion, the warping torsion, the antisymmetrical and the symmetrical distortion on the basis analogy with beam on the elastic foundation loaded by transverse actions and tension force at the end of the beam. Creating of influence lines of torsion, antisymmetrical distortion and symmetrical distortion internal forces of large concrete cable-stayed bridge with continuous box-girders with two spans. The application for real reinforced concrete Harp bridge over pond Jordán near Tábor in Czech Republic is investigated. Evaluation of internal lines for action according to Eurocode EN 1991-2.

Evaluation of web reinforcements in prestressed concrete box girders through shear-transverse bending domains

2020 ◽  
pp. 136943322098170
Author(s):  
Michele Fabio Granata ◽  
Antonino Recupero
Keyword(s):  
Analytical Model ◽  
Prestressed Concrete ◽  
3D Analysis ◽  
Box Girders ◽  
Element Analysis ◽  
Cross Sectional ◽  
Interaction Domains ◽  
Global And Local ◽  
Resultant Forces

In concrete box girders, the amount and distribution of reinforcements in the webs have to be estimated considering the local effects due to eccentric external loads and cross-sectional distortion and not only the global effect due to the resultant forces of a longitudinal analysis: shear, torsion and bending. This work presents an analytical model that allows designers to take into account the interaction of all these effects, global and local, for the determination of the reinforcements. The model is based on the theory of stress fields and it has been compared to a 3D finite element analysis, in order to validate the interaction domains. The results show how the proposed analytical model allows an easy and reliable reinforcement evaluation, in agreement with a more refined 3D analysis but with a reduced computational burden.

Prefabrication and Erection Technology of Wide Box Girders in Cross-Sea Bridge

2014 ◽  
Vol 1065-1069 ◽  
pp. 882-888
Author(s):  
Yue Huang ◽  
Xing Fa Wu
Keyword(s):  
Great Influence ◽  
Dead Load ◽  
Box Girders ◽  
Box Girder ◽  
Technical Problems ◽  
Line Segments ◽  
Temperature Load ◽  
Quanzhou Bay ◽  
Research Show ◽  
Better Than

In the approach spans of Quanzhou Bay Cross-sea Bridge, these standard spans are 50m or 70m , width is 20.05m.The approach spans have been built by using short Line segments precast and erection method. This is the first application in the cross sea bridges. According to characteristics of this project, the research on prefabrication and erection technology of wide box girders has been carried out to solve the technical problems in the process of construction. The research show that: 1)In precasting process , the vertical deformation of wide box girder is very small under dead load and temperature load etc. so the influence of prefabrication and erection accuracy can be ignored; 2)The temporary anchor using prestressed steel strand better than planished steel; 3) When using epoxy gasket to adjust geometric line shape, the thickness of cemented layer has a great influence on the linear adjustment;4)The epoxy gasket and bridge erecting machine should be used together, Alignment adjustmen could obtain satisfactory results.

Structural topology optimization of bridge girders in cable supported bridges

2018 ◽  
Author(s):  
Mads Baandrup ◽  
Ole Sigmund ◽  
Niels Aage
Keyword(s):  
Topology Optimization ◽  
Large Scale ◽  
Design Method ◽  
Optimization Method ◽  
Bridge Girders ◽  
Structural Topology ◽  
Box Girders ◽  
Box Girder ◽  
Fine Mesh ◽  
Further Development

<p>This work applies a ultra large scale topology optimization method to study the optimal structure of bridge girders in cable supported bridges.</p><p>The current classic orthotropic box girder designs are limited in further development and optimiza­ tion, and suffer from substantial fatigue issues. A great disadvantage of the orthotropic girder is the loads being carried one direction at a time, thus creating stress hot spots and fatigue problems. Hence, a new design concept has the potential to solve many of the limitations in the current state­ of-the-art.</p><p>We present a design method based on ultra large scale topology optimization. The highly detailed structures and fine mesh-discretization permitted by ultra large scale topology optimization reveal new design features and previously unseen eff ects. The results demonstrate the potential of gener­ ating completely different design solutions for bridge girders in cable supported bridges, which dif­ fer significantly from the classic orthotropic box girders.</p><p>The overall goal of the presented work is to identify new and innovative, but at the same time con­ structible and economically reasonable, solutions tobe implemented into the design of future cable supported bridges.</p>

Strengthening of box girder bridges with external prestressing - case study for the Langeland Bridge.

2021 ◽  
Author(s):  
Ulrik Sloth Andersen
Keyword(s):  
Additional Analysis ◽  
Box Girders ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Basic Principles ◽  
Structural Assessment ◽  
South Eastern ◽  
Girder Bridges ◽  
External Prestressing

<p>This paper presents the basic principles for strengthening of bridges and other structures through the use of external prestressing. A case study that includes strengthening of the approach spans for the Langeland Bridge in the south-eastern part of Denmark is included.</p><p>During a recent rehabilitation, corrosion of the post-tensioned tendons was discovered inside the box girders of the bridge. Additional analysis of the extent of the corrosion and a structural assessment was undertaken. Based on this, a strengthening project was carried out, and strengthening with external prestressing is currently being implemented.</p>

Sign in / Sign up

Export Citation Format

Share Document