CALCULATIONS
Determined Young Modulus :No
of
test
.
1
2
3
4
5
Mass
(Kg)
0.2
Length
I
(mm4)
(mm)
Newto
n (N)
1.962
L
(mm)
160
L
(mm)
409600
0
7.73
7.54
7.62
8.15
8.31
3.98
Average
PL
48 EI
E
(N/mm)
E=
5441.96
5579.09
5520.52
5161.51
5062.13
5353.04
P L
48 I
P = load applied
L = length of the satay stick
= deflection of the satay stick
I = moment of inertia.
Where,
Moment of Inertia, I
D2
I=
64
2
I=
(3)
64
I = 3.98 mm4
Therefore, the average E obtained is 5353.04 N/mm.
Determined the reaction of the truss :10
30
40
12.26
30
12.26
10
12.26 N
12.26
MB = 0
-(12.26)(0.3m) (12.26)(70) + RH (1.0) = 0
RH = 12.26N
fy = 0
- RB + 24.53 + 24.53 + 24.53 = 0
RB = 24.53N
fx = 0
Determined the deflection of the truss :=
F ' L
AE
where,
F' = internal force of each member
E = one unit load at point E
L = length of each member
A = area of each member
E = Youngs Modulus
= deflection
(Using Alternative Method and Unit Load Method)
Member
AC
AB
BD
BC
CE
CD
DF
DE
EF
EG
GI
GF
FI
FH
F' (N)
0
0
0
-12.26
-8.67
8.67
6.13
-6.13
17.34
-18.39
-18.39
0
0
18.39
E (N)
0
0
-1
0
0
0
-1
0
0
0
0
0
0
-1
L (mm)
141.42
100
100
100
141.42
141.42
200
200
282.84
200
200
200
282.84
200
A (mm)
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
7.069
E (N/mm)
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
5353.04
(mm)
0
0
0
0
0
0
-0.0324
0
0
0
0
0
0
-0.0972
HJ
HI
IJ
IK
KN
KJ
JN
JL
LM
LO
LN
NO
OP
OM
MP
18.39
0
0
-18.39
-18.39
0
17.34
6.13
0
8.67
-6.13
-8.67
0
-12.26
0
-1
0
0
0
0
0
0
-1
-1
0
0
0
0
0
0
200
7.069
5353.04
200
7.069
5353.04
282.84
7.069
5353.04
200
7.069
5353.04
200
7.069
5353.04
200
7.069
5353.04
282.84
7.069
5353.04
200
7.069
5353.04
100
7.069
5353.04
141.42
7.069
5353.04
200
7.069
5353.04
141.42
7.069
5353.04
141.42
7.069
5353.04
100
7.069
5353.04
100
7.069
5353.04
Therefore the total deflection is
-0.0972
0
0
0
0
0
0
-0.0324
0
0
0
0
0
0
0
0.2592m
m