Outline. 3 Linear Analysis 3.1 Analysis commands 3.2 Results. Box Girder Bridge 2/28

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1 ANALYS: linear static. CONSTR: suppor. ELEMEN: bar hx24l reinfo solid tp18l. LOAD: elemen face force prestr reinfo weight. MATERI: elasti isotro. OPTION: direct. POST: binary ndiana. PRE: dianai. RESULT: cauchy displa extern force green reacti strain stress total. Box Girder Bridge

2 Outline 1 Description 2 Finite Element Model 2.1 Geometry Box Girder 2.2 Geometry reinforcement 2.3 Geometry Support blocks 2.4 Properties reinforcement 2.5 Properties concrete box girder 2.6 Boundary Conditions 2.7 Loads 2.8 Mesh 3 Linear Analysis 3.1 Analysis commands 3.2 Results Box Girder Bridge 2/28

3 1 Description 3D Linear Static Analysis Model Unit: N, m Isotropic Elastic Material Reinforcement element Solid element Load & Boundary Condition Body Force Pressure Prestress for Reinforcement Constraint Table 1: Properties Concrete Young s modulus 2.4e10 N/m 2 Poisson s ratio Density 2400 kg/m 3 Reinforcement Young s modulus 1.96e11 N/m 2 Cross section m 2 Result evaluation Deformation Reinforcement stresses Box Girder Bridge 3/28

4 2 Finite Element Model For the modeling session we start a new project. We will set the gravity load direction in global Y-direction. Here for we will change the value of Direction of gravity in the property panel. Main menu File New [Fig. 1] Geometry Window Reference system Definitions Property Panel Direction of gravity [Fig. 2] Figure 1: New project Dialog Figure 2: Property panel:definitions Box Girder Bridge 4/28

5 2.1 Geometry Box Girder We will create a polygon sheet for the box girder cross section. Main Menu Geometry Create Add polygon Sheet [Fig. 3] Main Menu Viewer Viewpoints Top view Main Menu Viewer Fit all Main Menu Viewer show workingplane < OFF > We will change the viewpoint to a top view, fit the shapes in the Workspace window and hide the working plane. Figure 3: Geometry - polygon sheet outer contour box girder Figure 4: Geometry - Box girder Box Girder Bridge 5/28

6 We will create a polygon-sheet for the contour of the inner box Main Menu Geometry Create Add polygon sheet [Fig. 5] Figure 5: Geometry - polygon sheet contour inner box girder Figure 6: Geometry - Box girder Box Girder Bridge 6/28

7 We will subtract the two sheet to get the hole in the box girder Main Menu Geometry Modify Subtract shapes [Fig. 7] Figure 7: Geometry - subtract shapes Figure 8: Geometry - Box girder Box Girder Bridge 7/28

8 We will extrude the box girder sheet to get a 3D body shape Main Menu Geometry Modify Extrude shape [Fig. 9] Main Menu Viewer Viewpoints Isometric view 2 Main Menu Viewer Fit all Figure 9: Geometry - extrude shape Figure 10: Geometry - Box girder 3D shape Box Girder Bridge 8/28

9 2.2 Geometry reinforcement We will create a line for the reinforcement bar located in the top flange. This line will be copied and translate 6 times over 1.5 meter in positive X-direction to get 7 reinforcement bars in total. Main Menu Geometry Create Add line [Fig. 11] Main Menu Geometry Modify Array copy [Fig. 12] Figure 11: Geometry - Add line for reinforcement bar Figure 12: Geometry - Array Copy shape Box Girder Bridge 9/28

10 Figure 13: Model window Figure 14: Geometry Box Girder Bridge 10/28

11 2.3 Geometry Support blocks We will create a polygon sheet for the support block. Main Menu Geometry Create Add polygon sheet [Fig. 15] Figure 15: geometry support block Figure 16: Geometry Box Girder Bridge 11/28

12 We will copy the sheet of the support block 3 times and translate it to get 4 support blocks in total. The distance between the support blocks are 3.6 meters in X and 8.5 meters in Z direction. Main Menu Geometry Modify Array copy [Fig. 17] Main Menu Geometry Modify Array copy [Fig. 18] Figure 17: geometry support block one side Figure 18: Geometry array Duplicate shape Box Girder Bridge 12/28

13 Figure 19: Geometry window Figure 20: Geometry Box Girder Bridge 13/28

14 We will project and imprint the sheets of the support blocks on the Box Girder. Main Menu Geometry Modify Projection of shapes [Fig. 21] Figure 21: geometry - Projection support blocks on Box Girder Box Girder Bridge 14/28

15 2.4 Properties reinforcement To get reinforcement grid we will assign reinforcement properties to the grid shapes. Therefore we need a new material model for the steel and geometry properties. Main Menu Geometry Analysis Reinforcement property assignment [Fig. 22] Reinforcement property assignments Add new material [Fig. 23] [Fig. 24] Add new geometry [Fig. 25] Figure 22: Reinforcement bars, property assignment Figure 23: Add new material for steel reinforcement Box Girder Bridge 15/28

16 Figure 24: Linear material properties Reinforcement bars Figure 25: geometry properties Reinforcement bars Box Girder Bridge 16/28

17 2.5 Properties concrete box girder We will create a Linear material model for the concrete box girder. For a solid shape it is not necessary to define geometry properties. Then we assign the properties to the box girder. Main Menu Geometry Analysis Property assignments... [Fig. 26] Shape property assignments Add new material [Fig. 27] [Fig. 28] Figure 26: Property assignment Box girder Figure 27: Add linear material concrete Box Girder Bridge 17/28

18 Figure 28: Material properties concrete Box Girder Bridge 18/28

19 2.6 Boundary Conditions The support blocks will be supported Main Menu Geometry Analysis Attach support [Fig. 29] Main Menu Viewer Viewpoints Isometric view 2 Main Menu Viewer Fit all Figure 29: Geometry - Attach support Figure 30: Boundary conditions support blocks Box Girder Bridge 19/28

20 2.7 Loads We will apply the self weight of the box girder. Main Menu Geometry Analysis Global load [Fig. 31] Figure 31: Geometry - Self weight Box Girder Bridge 20/28

21 A distributed load of N/m 2 in negative Y direction will be applied to the top surface of the box girder Main Menu Geometry Analysis Attach load [Fig. 32] Main Menu Viewer Viewpoints Isometric view 2 Main Menu Viewer Fit all Figure 32: Geometry - Attach load Figure 33: Top pressure load Box Girder Bridge 21/28

22 We will prestress the reinforcement bars. Main Menu Geometry Analysis Attach load [Fig. 34] Figure 34: Geometry - Prestress load reinforcement Box Girder Bridge 22/28

23 We create 4 load combinations. Geometry menu Loads Open geometry load combination table [Fig. 35] [Fig. 36] Geometry Load Combinations Add a geometry load combination [Fig. 36] Figure 35: Geometry - Loads window Figure 36: Load combinations Box Girder Bridge 23/28

24 2.8 Mesh We will mesh the boxgirder with its reinforcements. First we will set the mesh properties. Main Menu Geometry Analysis Set mesh properties [Fig. 37] Main Menu Geometry Generate mesh [Fig. 38] Figure 37: Geometry - Set mesh properties Figure 38: Element size of 0.2 m Box Girder Bridge 24/28

25 3 Linear Analysis 3.1 Analysis commands Main menu Analysis Add analysis Analysis window Analysis1 Add analysis command Structural linear static Analysis window Analysis1 Rename Linear [Fig. 39] Main menu Analysis Run analysis Figure 39: Analysis: Linear static Box Girder Bridge 25/28

26 3.2 Results We will create a contourplot for the total displacement (DtXYZ) on deformed shape for load combination 4. Results browser Output Nodal results DtXYZ [Fig. 40] Figure 40: Total displacement for load combination 4 Box Girder Bridge 26/28

27 We will create a line diagram for the reinforcement cross section Forces (Nx) for load combination 4. Right-click on Nx and select line diagram. Results browser Output Reinforcement results Reinforcement Cross-Section Forces Nx [Fig. 41] Figure 41: Reinforcement Cross-Section Forces Nx for load combination 4 Box Girder Bridge 27/28

28 DIANA FEA BV Delftechpark 19a 2628 XJ Delft The Netherlands T +31 (0) F +31 (0) DIANA FEA BV Vlamoven TN Arnhem The Netherlands T +31 (0) F +31 (0)