finite element

15
QUESTION 1 A sign of dimensions 2.0 m x 1.2 m is supported by a hollow circular pole having outer diameter 220 mm and inner diameter 180 mm as shown in Figure 1. The sign is offset 0.5 m from the centerline of the pole and its lower edge is 6.0 m above the ground. Determine the Principle stress and maximum shear Stress due to a wind pressure of 2.0 kPa against sign.

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using abaqus 2D

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Page 1: Finite Element

QUESTION 1

A sign of dimensions 2.0 m x 1.2 m is supported by a hollow circular pole having outer

diameter 220 mm and inner diameter 180 mm as shown in Figure 1. The sign is offset 0.5

m from the centerline of the pole and its lower edge is 6.0 m above the ground.

Determine the Principle stress and maximum shear Stress due to a wind pressure of 2.0

kPa against sign.

Page 2: Finite Element

MODELLING TECHNIQUE,MESHING,BOUNDARY CONDITION

1) MODELLING TEHNIQUE

PART SELECTION

it use for modelling and analyze beam selection

In the Create Part dialog box (shown above) name the part and

Select “2D Planar”

Select “Deformable”

Select “Wire”

Set approximate size = 20

Page 3: Finite Element

PROPERTY SELECTION

1)Material selection

The technique to create material based on the question it use steel with the young moduulus 200GPA or 200e9

2)Profile

Double click on the “Profiles” node in the model tree

Name the profile and select “T” for the shape

Note that the “T” shape is one of several predefined cross‐sections

Enter the values for the profile

3.Section and section assignment

Name the section “BeamProperties” and select “Beam” for both the category and the type

Leave the section integration set to “During Analysis”

Select the profile created above (T‐Section) and select the material created above (Steel).

Assign the section will be selected the entire geometry and then select the section beam properties

Page 4: Finite Element

5.Assemly and step

The assembly for the modelling technique.choose create instance and the dependent mode

Step is the general procedure to choose the name load .In this case i choose the static general load.

Edit the output variable will be choose and i choose stress,displacement and force.

2) BOUDARY CONDITION

Users need to identify the location of the loads and types of load to be applied on nodes/ keypoints. Also the location of the constraints.Boudary condition is one of the load procedure.

In this case we are fixed and encastre the bottom.

The force will put on the sign as shown in the figure.

Page 5: Finite Element

3)MESHING

The process of applying and controlling nodes and elements to the model.

Highlight all members in the viewport and select Done

Select “Standard” for element type

Select “Linear” for geometric order

Select “Beam” for family

In the toolbox area click on the “Seed Part” icon

a. Set the approximate global size to 0.02

Encastre(fixed)

Distributed load

Page 6: Finite Element

RESULT AND DISCUSSION

a) Von misses

Page 7: Finite Element

b) Maximum principle of stress

Page 8: Finite Element

C)Minimum principle stress

The minimum principal stress is simply the eigenvalue that has the lowest magnitude.

Based on the result the red colour mean the mininum principle stress it can gived. Based

on the result minimum stress it can gived .The result show the minimum stress it can

gived until 0.It mean until no stress have.The maximum principal stress is the most

tensile (least compressive) and the minimum principal stress is the least tensile (most

compressive). 

Page 9: Finite Element

QUESTION 2

A tubular post of square cross section supports a horizontal platform as shown in Figure

2. The tube has outer dimension b=6 in. and wall thickness t=0.5 in. The platform has

dimensions 6.57 in. x 24.0 in. supports a uniformly distributed load of 20 psi acting over

its upper surface. The resultant of this distributed load is a vertical force P1. Determine

Principle stress and maximum shear Stress.

Page 10: Finite Element

2) MODELLING TEHNIQUE

i. PART

In the Create Part dialog box (shown above) name the part and

Select “2D Planar”

Select “Deformable”

Select “Wire”

Set approximate size = 100

ii. PROPERTY

- Create material

- Name : steel

- Select a mechanical, elasticity and elastic

- Young modulus E= 200Kpsi

- Poisson’s ratio = 0

- Create section- Assign section- Assign beam orientation

Page 11: Finite Element

iii. ASSEMBLY- Create instance- Independent- OK

iv. STEP- Step manager- Create Field Output- Check: MISES,MISEMAX,E,UT,RT

v. LOAD

- Create boundry condition

- Create load

- Load : 20Kpsi

- Moment: 29160

Page 12: Finite Element

vi. MESH

-Highlight all members in the viewport and select Done

-Select “Standard” for element type

-Select “Linear” for geometric order

-Select “Beam” for family

-in the toolbox area click on the seed part icon

-set a approximate global by number 4

vii. JOB

3) RESULT

i. Mises

Page 13: Finite Element

ii. Maximum Principal Stress