1. Structure
lecture2

2. 1-Axial loads only
2-Loads applies at end
points only
3- Elements are joined
by pins only

3. 1-Determine the force in each
member of the truss ?
 
 
 
 
0 1
0 2
0 3
2
tan tan
3
tan 0 4
3
X X X
Y Y Y
A Y
Y
X
X Y
F A B P
F A B
M B L Ph
B h
B L
B B



    
   
   

  
  




4. 2-Determine the force in each member of
the truss and indicate whether the the
members are in tension or compression ?
1 1
2 2
2 2
3
2 3 22 2
0
0
0
0 ( )
0 ( )
0 ( )
X X X
Y Y Y Y Y
A Y Y
F A P A P
Ph
F A B A B
L
Ph
M Ph B L B
L
Ph Ph
F F Tension
L L
F P F P Tension
F L h L
F F F Compression
Lh L
     

      
     
   
   
 
      
   




5. 3-Determine the force in each member of
the truss and indicate whether the the
members are in tension or compression ?
0
600
0
400
400*3 600*4 *6 0
600
200
X
X
Y
Y Y
C Y
Y
Y
F
C N
F
A C
M A
A N
C N
  

  
 
    





6. At joint A
At joint C
At joint D
1 2
2
2
1
3
0
5
4
600 0
5
600*5
750 ( )
4
3
750 450 ( )
5
X
Y
F F F
F F
F N Compression
F N Tension
 
     
 
 
     
 

  
 
  
 


4
5
0
600 ( )
0
200 ( )
X
Y
F
F N Compression
F
F N Compression
  
 
  
 


3 3
0
3
450 600 250 ( )
5
XF
F F N Tension
  
 
    
 


7. 4-Determine the force in each member of
the truss and indicate whether the the
members are in tension or compression ?
At joint B
At joint C
At joint A
0
500 sin 45 0 707.1 ( )
0
45 0 500 ( )
X
BC BC
Y
BC BA BA
F
N F N F N Compression
F
F Cos N F F N Tension
  
   
  
   


0
707.1 45 0 500 ( )
0
707.1 45 0 500
X
CA CA
Y
Y Y
F
F Cos N F N Tension
F
C Sin N C N
  
    
  
   


0
500 0 500
0
500 0 500
X
X X
Y
Y Y
F
N A A N
F
N A A N
  
   
  
   



8. *
1 1 3 2
1 1 3 2 2 2
2 22 2
2 2
2 2
1 3
1
3
0
0
0
0
0
( )
0
X
Y
Y
Y
C Y
Y
F
P F F F Cos
L
P F F F
h L
F
h
D P F
h L
h L
F P D
h
M D L P h F h
P h D L
F
h

  
   
 
    
 
  
 
   
 

 
    
 
  
 




9. 6-Determine the force in each member of
the truss and indicate whether the the
members are in tension or compression ?
1
Method of joints : we willbegainbyanalzingthe
equilibrium of joint D , and then proceed to
analyze joints Cand D
1
tan 26.57
2
At joint D
0
600 26.57 0
1341.64 ( )
0
X
DC
DC
Y
F
F Sin
F N Compression
F
   
  
 
  
 

  


/
/
1341.64 26.57 0
1200 ( )
At joint C
0
26.57 0 0
0
1341.64 ( )
At joint E
0
900 45 0
1272.79 ( )
0
1200 1272.79 45 0
DE
DE
X
CE CE
Y
CB
X
EB
EB
Y
EA
EA
Cos F
F N Tension
F
F Cos F
F
F N Compression
F
F Sin
F N Compression
F
Cos F
F
 

  
   
  

  
 

  
  





2100 ( )
Note , the equilibrium analysis of joint Acan be used to
determine the components of supports reaction atA
N Tension