Project 1

Aim:-

A portal frame has following details:

Portal beam having length of 4m and cross section of 300mm x 600mm (depth) and portal columns have height of 3m and cross section 300mm x 300mm.

1. The portal beam has two Bearing locations 1m from either end. The load from each bearing is 75 kN. Calculate the support reactions and displacement of each node.

2. Now change both the supports to fixed and compare the reactions and displacements with that of previous sub question.

3. Now provide 3 support conditions with 50 kN such that total load on the frame is same as that of Point 1. The bearings are 1m apart and 1st bearing is 1m from the end. Compare the reactions with that of sub question 2 and comment on the results.

4. Change the cross section of column to 300 x 400 mm such that 300mm width of column aligns with 300mm width of Portal beam. Rest all conditions remain same as that of sub question 2. Compare the portal beam and columns bending moment with that of sub question 2.

5. Now change the orientation of column such that 400mm size aligns with 300mm width of Portal beam. Compare the beam and column results with that of Sub question 4. Comment on the results.

Solution:-

1. The portal beam has two Bearing locations 1m from either end. The load from each bearing is 75 kN. Calculate the support reactions and displacement of each node.

Step (1):- Create portal frame in STAAD.pro

Step (2):- Assign Property as per

• Specification -> Define -> Rectangular -> Assign to selected beam assign

Step (3):- Assign support to portal frame

• One as Pined
• Second as a roller

Step (4):- Loads Assigning on portal frame

• 75 KN load on each bearing.

Step (5):- Analysis and result extraction

• Support reaction

• Displacement

2. Now change both the supports to fixed and compare the reactions and displacements with that of previous sub question.

Step (1):- Changing both support as fixed

• Support change from command file

Step (2):- Analysis and result extraction

• Support reaction

• Displacement

3. Now provide 3 support conditions with 50 kN such that total load on the frame is same as that of Point 1. The bearings are 1m apart and 1st bearing is 1m from the end. Compare the reactions with that of sub question 2 and comment on the results.

Step (1):- Creating new model using above step and applying loading as 50 kN at 3 support conditions.

Step (2):- Analysis and result extraction

Case 1 - One end pined other end as roller

• Support reaction

• Displacement

Case 2 - Both end as fixed.

• Support reaction

• Displacement

Que (4):- Change the cross section of column to 300 x 400 mm such that 300mm width of column aligns with 300mm width of Portal beam. Rest all conditions remain same as that of sub question 2. Compare the portal beam and columns bending moment with that of sub question 2.

Step (1):- Creating model as per the given question

• Change the cross section of column to 300 x 400 mm such that 300mm width of column aligns with 300mm width of Portal beam

Step (2):- Analysis and result extraction

• Maximum Bending moment

5. Now change the orientation of column such that 400mm size aligns with 300mm width of Portal beam. Compare the beam and column results with that of Sub question 4. Comment on the results.

Step (1):- Creating model as per the given question

• change the orientation of column such that 400mm size aligns with 300mm width of Portal beam

Step (2):- Analysis and result extraction

• Maximum Bending moment

• Shear force