Week 8 Challenge

1. Applying Load Exercise

For the structure modelled in previous exercise. Apply following loads

• Form a Load case as DL for Dead Load
• Apply Self weight
• Apply member load of 3 kN/m on the rafter
• Apply member load of 6 kN/m on the secondary beams
• Apply point load of 20 kN at node intersecting inclined member on the top chord.
• Form a Load case as LL for Live Load
• Apply member load of 4 kN/m on the rafter
• Apply member load of 7.5 kN/m on the secondary beams
• Form load combination 1.5DL+1.5LL

AIM :

To apply the load for the structure modelled in previous exercise.

PROCEDURE :

• Open the STAAD file.
• Go to Loading Tab, and click on Loading Tab and Add loading case.

• Select the Load Type as Dead and give the name as Dead Load and assign the Self Weight for different Strucutral Element under this load case.
• Selfweight has been assigned to all structural element.

• Now, similarly under the Dead Load Case add 3kN/m Member load on Rafter.

• Now, add 6 kN/m member load on Secondary beam.

• Now, assign the Nodal load of 20 kN on point of intersection of Rafter and inclined chord.

• Dead Load has been assigned.

• Now, similarly we create case for Live Load and apply the load as shown in below figure.

• Final Loading Diagram after applying Dead Load and Live both will be as shown in figure.
• Now, we will define a load combination of 1.5DL +1.5LL as shown in figure.

• Click on Add and the load combination has been added in Load Case.

Result :

All the given Dead Load and Live Load cases has been created succesfully.

2. Find Maximum Force and Minimum Force for member and present the STAAD result.

Continue previous challenge, Run the analysis and find following results on the member mentioned

• Run the analysis
• Find the Maximum Moment in the Secondary beam for 1.5DL+1.5LL case
• Find the Maximum Axial force on the inclined bracing and identify the member having the maximum force for 1.5DL+1.5LL case
• Identify Bottom chord of Truss having Maximum shear Force & Maximum moment for 1.5DL+1.5LL case and present the values.

AIM :

To run the analysis and find following results on the member mentioned

PROCEDURE :

• Since, the loading has been done already, we will run the analysis.
• Go to Analysis Tab, click on last load case and click on Define Commands.

• Now, click on All option and then click on Add.

• Now, click on Run Analysis on Tab.

• Analysis will be going on and window will pop up after the analysis.
• Click on View Output file to view the results.

• Final Result of the analysis will be pop-up in different window as shown below.

• Now, we will find the Maximum moment in the secondary beam for 1.5DL + 1.5LL case.
• Go to Post Processing Option on Left Side. Go to View and select on Secondary beam to view.

• After only selecting only Secondary Beams, Go to Result Tab, and select Mz to view the Bending Moment Diagram.

• Go to annotate option to view the Maximum Bending Moment.

• Now, we can get the maximum values of Bendig Moment as 54.268 kN m.

• Similarly, we will now find the maximum axial force on the inclined bracing for 1.5DL+1.5LL Case.

• Maximum Axial force we got as 153.934kN on Beam Number 1160 and 1161.
• Now, we can get the Maximum Shear Force and Maximum Bending Moment for the bottom chord of the Roof Truss as 2.40 kN and 3.925 kN-m.

Result :

These are following results obtained on analysis

1. Maximum Moment in the Secondary beam for 1.5DL+1.5LL case = 54.268 kN-m.
2. Maximum Axial force on the inclined bracing and identify the member having the
3. maximum force for 1.5DL+1.5LL case = 153.934 kN
4. Maximum ShearForce and Maximum Bending Moment for the bottom chord of the Roof Truss as 2.40 & 3.925 kN-m.

3. View and Rectify the Warning, instabilities in the structure

For the attached STAAD file identify the Warnings and fix the same and run the analysis.

AIM :

To identify the Warnings and fix the same and run the analysis for the given STAAD File.

PROCEDURE :

• After running the analysis 8 warning messages were displayed as shown in below figure.

• Reason for Error: A joint exists where the only structural components connected at that node are truss members, there is no rotational stiffness at that node along any of the global d.o.f.
• Remedy: Go to Speciification menu to create Master Node.

• Run the analysis again to see if there is any warning message left.
• We can see that warning message has been resolved.

Result :

Analysis has been done and 8 warning messages showing were resolved successfully and analysis report with O warning message has been obtained.

4. Design Parameter exercise

In continuation to challenge 1, Apply Design parameter for structure modelled for code IS800:2007.

• Effective Length Lx, Ly, Lz for beams, Truss elements
• Effective length factors Ky, Kz for Columns
• Apply other design parameters for respective members

AIM :

To apply Design parameter for structure modelled for code IS 800:2007.

• Effective Length Lx, Ly, LZ for beams, Truss elements
• Effective length factors KY, Kz for Columns
• Apply other design parameters for respective members

PROCEDURE :

• Go to analysis and design tab, select all the structural members and assign steel as the basic material.
• On the right hand side, select the IS 800 code as shown in below figure.

• Now, define the parameter for the like Ly,Lz for beams and trusses and Ky,kz for columns.

• Now, run the analysis again to see that there is no error.

• Other parameters have also been applied.

Result :

Design parameter has been successfully applied to the modelled structure in STAAD Pro.