Solving Truss Problems: Need Help!

  • Thread starter Thread starter Joelllllll
  • Start date Start date
  • Tags Tags
    Trusses
Click For Summary
The discussion centers on solving truss problems, specifically calculating reactions at points A and B. One user reports their calculated reactions as Ax = -50 kN, Ay = 72 kN, and By = 128 kN, but expresses confusion over their results for internal forces. Another user suggests using moments to find Ay and By, providing a method that yields Ay = 96 kN and By = 104 kN, and questions the omission of a 50 kN force in the moment equation. The conversation emphasizes the importance of correctly applying equilibrium equations and considering all forces acting on the truss. Clarifying these calculations can help resolve discrepancies in the results.
Joelllllll
Messages
5
Reaction score
0
Need help with trusses!

Hey guys
So I'm trying to solve this truss problem and get all the reactions of the trusses
I've done it so many times but my equations never work out and I get crazy answers :\
I've found the reactions at A and B
Ax=-50kN
Ay=72kN
By=128kN
My answers for tryingto solve it are
Pac=-90kN
Pad=104kN
Pce=6.66kN
Pcd=-177.3kN
Pde=-295.5kN
Pdb=132.4kN
I just can't see where I went wrong?
Can someone help me out here?:(
Thanks
 

Attachments

  • Untitled.jpg
    Untitled.jpg
    9.7 KB · Views: 448
Physics news on Phys.org


I found Ax= -50 too, but I found Ay=96kN and By=104kN.

To find Ay and By I used moments. Taking the moment around A you find the equation.

Ma = 100kN(2.25m) + 100kN(4.25m) - By(6.25m)

When you solve this I get By = 104kN. From their you just take 200kN - 104kN and that gets you Ay=96kN.

I think this should help you get on the right track from here.
 


What about the 50kN force?
Why didn't you use that in your moment equation?
 

Thread 'Does acceleration affect impact energy vs constant velocity?'

I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...
View full post »

Similar threads

Weird Statics Truss Problem - Finding reactions
  • · Replies 11 ·
Replies
11
Views
4K
Need help on some questions - Moments, Bearings & Trusses
  • · Replies 3 ·
Replies
3
Views
3K
Statics Truss Problem Involving Method of Sections
  • · Replies 1 ·
Replies
1
Views
9K
Statics: bad solution to simple truss problem regarding determinancy
  • · Replies 5 ·
Replies
5
Views
6K
Understanding Truss Problems: Solving for Reaction Forces and Member Forces
  • · Replies 6 ·
Replies
6
Views
5K
How to Solve a Space Truss Statics Problem with Ball and Socket Supports?
  • · Replies 1 ·
Replies
1
Views
3K
Need help clarifying statics problem.
  • · Replies 1 ·
Replies
1
Views
2K
Structures (Civil Engineering) - Help with Planar Truss and Stress Analysis
  • · Replies 21 ·
Replies
21
Views
5K
Truss Problem 6.30: Urgent Help with Stress Calculation | 1020 Steel
  • · Replies 1 ·
Replies
1
Views
2K
Two Beam Problem: Solve 6 Equations, 7 Unknowns
  • · Replies 12 ·
Replies
12
Views
2K