Bridge analysis using Ansys mechanical Apdl. Solid mechanics assignment

Table of Contents

TASK 1

Create and present FE model of the bridge

1.10 Creation of the Finite Element model
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Discuss real constants, material model and element type chosen for the FE analysis
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14

Task 1.12
Justification of the element type selected

Task 1.13
Present meshed FE model and discuss the procedures used for it
Figure 16
Figure 17
Figure
Figure 19

Task 1.14
Explain the boundary conditions used for the modal analysis
Figure 20
Figure 21
Figure 22
Figure 23
Figure 24
Figure 25
Figure 26

Task 1.15
Present your post processing results in textual and graphical form
Figure 27
Figure 28
Figure 30
Figure 32
Figure 33
Figure 34
Figure 36

Task 1.16
Discuss the solver used for this analysis

Task 1.17
Refine the FE model with more elements and conduct analysis
Figure 39
Figure 40

Task 1.18
Presenting the post processing results in textual and graphical form for the no of element division of 100 for the refined analysis and compare it with the results of previous model.
Figure 41
Figure 42
Figure 44
Figure 46
Figure 48

Table 1.1. Showing the comparison of the results gotten from the analysis

Discussion and Conclusion

References

TASK 1

Create and present FE model of the bridge

(Discuss the procedure used as well)

In modelling this Finite Element model of this bridge, different system are to be used in other to solve the given problem and achieve the final result required. Different dimensions can be used to solve this problem such as 1-Dimensional (1D), 2-Dimensional (2D) and 3- Dimensional (3D) finite element can be ensured. In this particular work, the bridge is in form of a line making a 1-Dimensional analysis to be the most competent to be used in solving this problem. Different steps shown below is used to obtain the Finite Element model of the bridge.

1.10 Creation of the Finite Element model.

- Creating the Keypoints: In other to create this finite element model, several methods can be used but in this work of bridge creation, creation of keypoints is been used to create this model. The process is shown below on how the keypoints is been assigned in the X, Y and Z co-ordinates.

ANSYS Main Menu>>Preprocessor>>Modelling>>Create>>Keypoints>>In Active CS>>then put in the keypoint values as shown in the coordinates boxes>>Click Ok

Showing plotted keypoint coordinates

Keypoint No. 1

X coordinates - 0 µm

Y coordinates - 0 µm

Z coordinates – 0 µm

Keypoint No. 2

X coordinates - 200 µm

Y coordinates -0 µm

Z coordinates – 0 µm

Abbildung in dieser Leseprobe nicht enthalten

Figure 1

Abbildung in dieser Leseprobe nicht enthalten

Figure 2

Abbildung in dieser Leseprobe nicht enthalten

Figure 3

Abbildung in dieser Leseprobe nicht enthalten

Figure 4

- Joining both lines: After the keypoints has been assigned, the two lines is been joined together to make the clamped-clamped bridge.

ANSYS Main Menu>>Preprocessor>>Modelling>>Create>>Lines>>Straight Lines>>Click on the Keypoint 1 and 2>>Click Ok

Abbildung in dieser Leseprobe nicht enthalten

Figure 5

Abbildung in dieser Leseprobe nicht enthalten Figure 6

Abbildung in dieser Leseprobe nicht enthalten

Figure 7

Task 1.11

Discuss real constants, material model and element type chosen for the FE analysis

First for the creation of this model the structural type is been selected from the Preference because resonant frequencies and mode shapes of the clamped-clamped bridge are to be extracted and presented.

ANSYS Main Menu>>Preference>>Click on Structural in the Box and Click Ok

Abbildung in dieser Leseprobe nicht enthalten

Figure 8

- Element type: In this analysis, the 3 node 189 was chosen as the element type because the beam 3 has a uniaxial element with tensions, compressions and bending capabilities. In each node of the element is also a DOF of 3 Dimension which translates on x and y nodal direction and rotates about z nodal axis.

ANSYS Main Menu>>Preprocessor>>Element type>>Add/Edit>>Add>>Select Beam>>3Node 189>>Ok>>Close in the define element type window.

Abbildung in dieser Leseprobe nicht enthalten

Figure 9

Abbildung in dieser Leseprobe nicht enthalten

Figure 10

- Adding the Sections: After which the section will be added under Breadth which is 25µm and Height which is 0.6µm for the area section of the clamped-clamped bridge.

ANSYS Main Menu>>Preprocessor>>Section>>Beam>>Common Section>>Add the B and H to the values assigned>>Click Ok

Abbildung in dieser Leseprobe nicht enthalten

Figure 11

- Material Model: The Structural, Linear, Elastic and Isentropic are chosen respective in other to assign the material model. The material properties are the Modulus of elasticity which is 170e9 and the Poisson’s ratio which is o.270.

ANSYS Main Menu>>Preprocessor>>Material Props>>Material Model>>Structural>>Linear>>Elastic>>Under Ex put 170e9 and under PRXY put 0.270>>Click Ok>> Click Density>>Density dialogue box appear>>put 3000Kj/m for the Density and Close.

Abbildung in dieser Leseprobe nicht enthalten

Figure 12

Abbildung in dieser Leseprobe nicht enthalten

Figure 13

Abbildung in dieser Leseprobe nicht enthalten

Figure 14

[...]