SEGI UNIVERSITY
KOTA DAMANSARA
B.ENG (HONS) CIVIL ENGINEERING
MECHANICS OF MATERIAL ECV 3143
buckling test
LAB 02
S.N NAME STUDENT ID
O
1 AHMED MAHMOUD SALAMA SUKD1504363
ELQAZAZ
Submission of Report : 25/4/2017
Submitted To : Mr. Ir Pan
TABLE OF CONTENTS
1. Abstract ............................................................... 3
2. Objective ............................................................... 3
3. Apparatus ............................................................... 3
4. Introduction ...................................................... 4
5. Procedure ..................................................................4-10
6. Result & Calculation ................................................... 9-12
7. Discussion ................................................. 13
8. Conclusion ............................................... 13
9. Reference ..... .........................................13
10. Apparatus 14
ABSTRACT
At the beginning of the experiment I will mention the most
important use of columns . Columns are used in part design
especially rocket wings. It supports load but most often a critical
load is determined when twisting occurs. This occurs either by
defects in the column or by loading .This test was arranged with
confirmed default predictions when columns buckle and how to
increase critical load. It was accepted that The longer columns were
supposed to buckle sooner and also simply backed up. See also The
clamped end columns are also further established by a factor of 4.
Another assumption was that increasing the bending ratio of
columns would reduce their critical stress. The experiment analysis
was prepared by loading varying lengths of beams with both a
simple support and clamped
2
fixiti .
OBJECTIVE
1. To determine the effect the slenderness ratio has on the load
carrying strength of pin ended columns.
2. To determination critical buckling loads for columns with support.
3. To checking the Euler theory of buckling.
4. To verify the effect of different material parameters
5. To keep an eye on short intermediate and long column behavior
under the
application of a compressible load.
APPRATUS
Column buckling machine.
S4 and S6 metal bar
Ruler
Dial gauge
Vernier caliper
INTRODUCTION
Deformation of columns under load is an important property of
materials that must be considered for planning and designing
calculations.(Leonard Euler) was the first scientist to work on it and
derived the equations that specialized in this field. In the buckling
test, the maximum load which is the largest load column can
support before deformation is associated with the yong coefficient of
moment of inertia and sample. If appropriate material is used so the
3
result going be reliable and accurate enough.
A column under a concentric axial load exhibiting the characteristic
deformity of buckling
If the load on a column is applied through the center of gravity of its
cross section, it is called an axial load. A load at any other point in
the cross section is known as an whimsical load.
a. Columns and supports in construction and steel engineering
b. Lifting spindles in lifting gear.
c. Stop rods for valve actuation and connecting rods in motor
construction .
d. Piston rods for hydraulic cylinders
PROCEDURE
Some of the instruments were used for experiment such as test
device( machine) vernier caliper, ruler, mild steel bar S4 and S6 bar
and force gauge and measuring gauge which were attached in
machine by a guide column, a piece of paper and a pen to record
data
PROCEDURE (PIN PIN)
1) The testing machine, The The test model were set well in vertical position, as shown
4
in figure as shown in figure no.1 .
Fig 1.
A mild steel bar S4 pin-pin was measured with a long metal ruler and recorded the
length which was64.8 cm long, height 0.1 cm and base was 1.80 cm
as shown in figure 2
Fig 2
2) Guide column and load cross bar were adjusted as we required .
3) A long thrust with notch was inserted into the guide bush of the load cross bar.
4) A steel bar S4 was inserted with in the notch and let it hold promptly as
shown in figure 3.
5
fig 3
Fig 4
5) A measuring Measure was aligned to the middle of the steel sample using the
supports clamps and it was set at a right angle to the direction of buckling.
6) The measuring gauge was pretighened to 12.885 mm deflection with the
adjustable support.
7) The specimen bar load was subjected by using the load nut when the force was
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applied 100N as shown in figure 4 and the specimen bar was bent when the
forced was applied 950 N and as shown in figure 5.
8) Then we applied different forces one by one, reading was shown in force
gauge and deflection reading was shown in measuring gauge and recorded as
shown in the table below
Fig 5
9) Then we made a table to record the readings as shown in the table below.
Force (N) Deflection(mm)
100 0
200 0.205
7
300 0.385
400 0.620
500 0.910
600 1.390
700 2.245
800 3.97
PROCEDURE (PIN FIXED)
1. The testing machine, force gauge were set well in vertical position, other tools
were in good condition as well and as shown in figure as shown in figure no 6.
Fig 6.
2. A mild steel bar S6 fixed-pin specimen were measured with a long ruler and on
record the length which was 64.7 cm long, height 0.1 cm and base was 1.8 cm as
shown in figure 6
8
Fig 6
3. Then we did the same steps as the first experiment and recording the outputs
shown below in table no 2 and which was recorded during experiment.
Force(N) Deflection(mm
)
100 0
150 0.830
200 1.235
250 1.760
300 2.510
RESULT & CALCULATIONS
350 3.550
Pin-pin joint (S4) :
400 5.495
9
450 7.785 Length =650 mm
Dimensions =650 17 1.5mm
500 12.510
Modulus of elasticity = 210000 N/mm
Force (N) Deflection(mm)
100 0
200 0.205
300 0.385
400 0.620
500 0.910
600 1.390
700 2.245
800 3.97
Graph of Load (N) vs Deflection (mm) for the Pinned-Pinned Joints
900
800
700
600
500
Load, P (N) 400 Linear ()
300
200
100
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
Deflection d (mm)
10
CALCULATIONS
lk = L lk = 650 mm
Area = breadth * height
=1.5 mm X 17 mm
= 25.5 mm
= = = 4.78 mm4
= = 23.45 N
Force(N) Deflection(mm
)
Fixed pinned joint (S6 )
100 0
Length =650 mm
Dimensions =650 17 1.5mm
150 0.830
Modulus of elasticity = 210000 N/mm
200 1.235
250 1.760
300 2.510
350 3.550
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400 5.495
450 7.785
500 12.510
Graph of Load (N) vs Deflection (mm) for the fixed-Pinned Joints
600
500
400
Load, P (N) 300
Linear ()
200
100
0
0 2 4 6 8 10 12 14
Deflection d (mm)
lk =. 0.7L lk = 455 mm
Area = breadth * height
=1.5 mm X 17 mm
= 25.5 mm
= = = 4.78 mm4
= = 47.85 N
DISCUSSION 12
Materials vary according to their different mechanical characteristics
and must be tested before use for construction and engineered
structured In this experiment we tested the torsion of steel column
and pulled it according to the table and agreed outputs and
discovered some errors
There are three reasons for the first error is that the columns have
been used repeatedly to repeat this experiment and this causes
weakness and strain It was better to use the newly manufactured
columns for each experiment to reduce the error ratio
Each experience came in a style that increased lift rate decreased
critical stress. This shows that it is best when designing columns to
resist twisting should be kept as short as possible, and also should
be installed at the end
There has also been a measurement error due to poor testing of bad
samples and poor calibration equipment. Torsion samples have been
seen several times prior to this test, and the clamps are not aligned
to the parallel force position along the beam
CONCLUSION
Each experiment followed the trend, which lead to an increase in critical altitude.
This demonstrates that when the twisting torsion columns are designed it should be
kept as short as likely and also should be installed at the ends.Another way that has
not been tested in this experiment is to increase the column stiffness by using
engineering properties and materials. As for the ratio of the grade to the critical data
has been supported despite the fact that there are some errors than the thirtical loads
of the stabilized case
REFERENCE
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abstract and Introduction Available at :
https://www.slideshare.net/asghar123456/buckling-test-engt110
Apparatus and OBJECTIVE Available at :
file:///C:/Users/User/Downloads/Buckling%20Test%20Proper%20one
%20(2).pdf
Result and Calculation Available at :
https://en.wikipedia.org/wiki/Buckling
DISCUSSION and Conclusion Available at :
https://www.scribd.com/doc/30744553/Column-Buckling-Lab
Apparatus:
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