Truss Analysis using joints method 2D analysis

AI Thread Summary
The discussion focuses on analyzing a Warren truss using the joints method for 2D analysis, specifically at joint B. The user calculated the force in member AB as 28.87 kN and established equilibrium equations for vertical and horizontal forces. Feedback indicates that while the magnitudes are correct, it is essential to specify whether AB is in tension or compression. Additionally, a 5 kN applied force at the end joints was noted as not affecting the member force results. The user is encouraged to solve for the force in member BC for a complete analysis.
FlorenceC
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Given a warren truss, where the load is 2kN/m so the weight per joint is 10kN, since the ends are supported by ground not truss, can anyone please verify my way of solving for the tension and compression at point B.
See attachment

Your help is greatly appreciated.

So I figured out that AB is 28.87 and with a FBD for joint B I ended up with the two equations:
net Fy = 0 and net Fx = 0
so, ABy=BCsin60 = 25
and ABx + BCcos60 = -BD = -28.87

Is this right?
 

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The magnitudes are OK, but be sure to indicate tension or compression. For example, is AB tension or compression?

Also note that you left out the 5 kN applied force at the end joints, which does not affect your result for the member forces noted.

Solve for BC.

I need a mirror...
 

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