ES 221: Mechanics of Solids
Experimental and Analytical Study of a Mechanical System
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General
A picture may be worth many words. A video may help learn much better. A live experiment may be
even more insightful. The understanding of concept increases manifold if the experiment is designed
and performed by oneself. In that spirit, Indian Institute of Technology (IIT) Gandhinagar encourages
learning-by-doing. Through this project, we will hope to learn-by-doing and learn-by-watching. Students
from a tutorial section will work in a group of five. Each group will conceive an experiment, fabricate
the experimental specimen, conduct the experiment, perform analytical simulation, and compare the
experimental results with the simulated values. The scope of projects can be broad. The experiments
may be inspired from any field of science and engineering. However, it is desirable that the experiments
are linked to the course. A report will be submitted at the end of this project. In addition, each group
will observe experiments and simulations from two other groups from sections different from their own.
These observations also will be included in the report.
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Goals
The goals of this study are following.
(i) Get hands-on experience of fabricating a specimen and performing an experiment related to concepts covered in the course.
(ii) Perform a closed-form analytical and numerical simulation.
(iii) Compare the experimental and simulated results.
It is hoped that students will develop some appreciation towards analytical modelling of physical systems
by the end of this project.
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Potential projects
Solved or unsolved examples from the relevant books (e.g., Crandall et al., Popov, Gere and Timoshenko,
Beer et al., Hibbeler) may serve as starting point for developing experimental models. Note that only
some ideas may be practicable. It is also important to understand that even practicable ideas may
work only when appropriate dimensions and material properties are considered. Please note that
examples from later chapters may also be proposed to begin with. Modifications in the proposal can be
considered at a later stage. Students are encouraged to attempt challenging problems. Overall effort
will be considered in the evaluation. Some hints for the project are as follows.
ˆ Determination of strains in a slender member under transverse loads
ˆ Deflection in structure (e.g., truss bridge, three-dimensional truss, made of members connected
with special joints) subjected to loads
ˆ Stresses developed due to torsion
ˆ Stress concentrations around openings
ˆ Stability of slender columns under different loading conditions
ˆ A set-up involving connections, pinned/fixed connections, friction etc.
ˆ Assessment of shear strength of joints.
Analytical solutions can be obtained using the procedures developed as part of this course. Numerical
solutions can be obtained using commercially available software programs such as SAP2000 or ANSYS
(these packages are available through ISTF).
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Structure
Activities of this project are identified in Table 1. The project accounts for 15% of the total weight of
the course. It will be graded based on the final report (70%), and the assessment by a panel of judges
(30%). Due dates for different activities are noted below. Final report will be submitted on April 18.
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Activity
Name
Table 1: Structure of the project
Description
Submit a brief project proposal incorporating the following.
Due on
Project proposal
(i) Group Name: You may pick a mechanistic name for
your group.
(ii) Name, roll number and tutorial section of group members. Note that all members should be from same tutorial
section.
(iii) Title of the proposed project
(iv) Description of the proposed project. It should include the schematics, dimensions, proposed methodology for performing experiments and simulations, and expected results.
(v) Tentative budget (you may get in touch with your tutors for financial aspects, for example, reimbursements).
It should be noted that a formal bill is required for reimbursements.
Feb 11
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Progress report
Mar 17
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Development of
experimental specimen
Project proposal should be submitted through the Google
Classroom by the due date.
A brief report (in hard copy) should be submitted outlining the analytical calculations, progress in fabrication
of specimen etc. This report will be graded as satisfactory or unsatisfactory. An unsatisfactory grade will imply that the project will not be graded.
The group should complete the fabrication of the specimen.
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Performing
experiments
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Final report
Perform experiments to measure the relevant quantities.
A panel of judges will evaluate the work. Their scores
will count for 30%.
The final report will comprise the following items. You
need to be very brief and to the point.
(i) Title page
(ii) Declaration of work done by each member with signature (the report will not be graded in the absence of the
declaration)
(iii) Acknowledgements
(iv) Abstract
(v) Introduction
(vi) Model development: Background calculation, development of the experimental model, description of geometry, material etc.
(vii) Experimental results: List of experiments, key experimental results, discussions
(viii) Simulation: Compare the experimental observations with analytical and/or numerical simulations. All
necessary derivations and details of numerical model development (e.g., SAP2000, ANSYS) should be provided.
(ix) Details of experiments and simulations from two
other project groups.
(x) Summary and conclusions
The final report will count for 70%.
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Apr 6
Apr 8-9
Apr 18