Experiment-7
pdf
School
University of Central Oklahoma *
*We aren’t endorsed by this school
Course
2143
Subject
English
Date
Dec 6, 2023
Type
Pages
7
Uploaded by HighnessScorpionMaster539
University of Central Oklahoma
Experiment 7 - Beam Experiment
Dylan Robinson, Joshua Jackson, and Kaleb Paddock
Dr. Adnan Al-Ibadi
Thursday 1:00 PM
11/10/22
ABSTRACT
In experiment 7 for the strength of materials lab, we employ the use of strain gauge
system in order to determine the static deformation of a cantilever beam structure, as well as
learn some of the basics involving the basics of finite element analysis.
[1]
In aerospace engineering, aircraft wings’ lateral structural elements are similar to that of
bridge beams. They are referred to as spars and they carry the main loadings induced from lift.
Figure 1 shows equations related to spar shear force and bending moment.
Figure 1. Aircraft Wing Spar
THEORY
For this experiment,we are asked to consider the deformation of a cantilever beam
structure using the theories and concepts behind finite element analysis in conjunction with a
strain gauge system. For our particular experiment, we use the strain gage system on a
cantilever beam and gather experimental data from that.
EQUIPMENT
As stated previously, the main piece of equipment that we will be using in this particular
experiment is a strain gauge system. This tool is particularly useful when trying to determine
deformation on a body, and in this particular experiment in which we are testing on a simple
apparatus, it is relatively lightweight work on the end of this device.
This device’s main components consist of a single conducting strip on a film that “zig
-
zags”
back and forth along the longitudinal axis of the beam. The gauges are able to detect
strain in the beam in that direction, and thus will be able to give us very accurate measurements
for the total deformation on the specimen.
Shown below is a diagram of the circuit that is used for the strain gauge. Figure 3 shows
the exact components used.
Figure 2. Strain Gage Diagram
EXPERIMENTAL METHOD
In this experiment, our part of setting up the experiment was very limited. However, as
stated previously, our particular experiment involved a cantilever beam setup with an
attachment point for an added load point (weight) towards the end of the beam, and given
various loads applied, we measured the deformation of the specimen from the strain gauge
system. Shown below in Figure 3 is the apparatus setup.
[3]
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Figure 3. Strain Gage Used
EXPERIMENT RESULTS
Below in figure 3 is the data we collected from the different loads applied on the
specimen. The calculations for this table were carried out by using the following formula, shown
below in equation 1.
EQ: 1
In equation 1 listed above, V
0
is the voltage in the strain gauge, R
2
and R
3
are resistors
and are equal in value for this particular instance, and V
s
is the voltage of the voltage source,
which in this case is 15 volts. Using this equation, we are able to calculate the following results
for each of the different strain values.
Table 1: Experimental data collected.
From the table above, we are able to construct the following graph, which depicts the
values of the strain calculated due to the force being applied. This graph was constructed to be
able to hopefully more easily display the data we collected.
Graph 1. Strain vs. Load Applied
Ansys Results
The following figures were the outcome of following the Ansys procedure outlined in the
lab manual.[1]
Validation and Discussion
Comparing Results and Ansys Results, we are able to see the differences between
computed and experimentally derived strain between the materials tested. Using this
methodology, we could compare many different metals quickly, and cheaply.
Conclusion
In conclusion, the objective of the experiment was to compare experimental strain and
to validate our results using Ansys. We were able to meet these objectives. As
discussed in the validation section using the tests mentioned above engineers can
perform complex trade studies on many different materials.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
References
[1] Khandaker, M. (2021). Laboratory Manual for Strength of Materials Lab. Department
of Engineering and Physics (UCO)
[2] https://www.sciencedirect.com/topics/engineering/main-spar
[3] Hibbeler, R. C.
Mechanics of Materials
. Pearson, 2022.