Finding displacement at a point in truss

[fonseh]

Homework Statement

For the circled part , how to get the +1.33 , -1.67 , +1 ? What are they ? Are they the µ ?

Homework Equations

The Attempt at a Solution

What is µ ? How to get the value ? It's not stated in my book though

 

[PhanthomJay]

Homework Statement

For the circled part , how to get the +1.33 , -1.67 , +1 ? What are they ? Are they the µ ?

Homework Equations

The Attempt at a Solution

What is µ ? How to get the value ? It's not stated in my book though

I would be surprised if it wasn't stated in your book. Your attempt is a question, not an attempt. The value of u is the dimensionless ''force' in each member when a unit load of 1 (dimensionless) is applied at the given joint in the direction of the displacement you want to calculate for that joint. You should now make an attempt to understand the given solution.

 

[CivilSigma]

The method used here is the virtual work method for trusses and mu are the internal force in each member due to a unit load of 1 applied at point E.
Positive values indicate that the member is under tension forces, negative under compression forces