16.20 is a junior and senior level course which provides the fundamental
knowledge to understand, analyze and design load-bearing structures. Although
the focus is on aerospace applications, the theory and the majority of the
applications are equally relevant in other areas of structural analysis. The
first part of the course provides an in-depth study of three-dimensional
elasticity theory, including the concepts of stress and strain, equilibrium,
compatibility and elastic constitutive laws and anisotropic materials. The
second part focuses on classical analytical solution procedures of the boundary
value problem of isotropic linear elasticity in situations of important
practical application. This includes states of plane strain, plane stress and
torsion. This is followed by the analysis of structural elements with
an increasing level of complexity: simple beam theory, combined bending, shear,
and torsion of thin-wall shell beams, and buckling.
Students who successfully complete 16.20 will have the ability to:
- formulate and apply appropriate mathematical and numerical
models to predict the state of stress and deformation of one, two and
three-dimensional aerospace structures.
- explain the limitations of the models, assess their
applicability to realistic configurations and estimate the errors resulting
from their application.
- apply the concepts learned in the course to assess and
explain the possibility of failure in aerospace structural components
and systems.
Module-specific measurable outcomes are provided at the beginning of each
module notes.
16.20 and 16.90 are being offered with a new pedagogic approach this semester.
While there are some differences in the details of the organization of 16.20
and 16.90, our goals for changing the pedagogy are the same.
The basic objective of the new approach is to de-emphasize the role of
traditional lectures in favor of a much more active student participation
and instructor-student engagement. Class sessions will adopt a tutoring
style, where we are going to learn the subject matter by solving problems
together. This is sometimes known as the apprentice model of learning. To do
this in an effective manner, a number of conditions need to be satisfied:
- student attendance in person or via remote access is primordial.
- student preparation through a thoughtful advance reading of the
material assigned and the attempted advance solution of the problems
given.
- student preparation of questions prior to each session and proactive
inquiry and discussion with instructors and peers during class.
While this approach places increased demands on students before and during
class sessions, it is hoped that much more efficient learning will be achieved
and that homework assignments and test preparation will require less time.
In order to facilitate the process of recalling class discussions, all the
material presented and discussed will be recorded and made available online
via Webex or AdobeConnect.
In order to encourage students to respond to this format, an important part
of the grade (20\%) will be attributed to class participation. This will be
assessed on an individual and daily basis.
In addition, students will be allowed the flexibility to participate in the
class activities remotely via live broadcast of the class sessions. The hope
is to create an environment that provides some flexibility for students to
participate in activities that may require some time away from the classroom
(e.g. participating in an engineering competition; presenting at a conference;
etc).
If as the semester proceeds you have suggestions for how we can better meet
these goals, please let us know!
16.20 will broadcast the instructor's computer and voice during class sessions
through a Webex or AdobeConnect. This will allow students that cannot be in
the classroom to observe most and engage in many of the classroom activities
if they have access to the Internet. As well, movies of each Webex session
will be made available typically within a day of the session. Details for
participating in a Webex class session and accessing the movies of past class
sessions will be available on the course web site.
While these options for remote access will be available, we believe the best
opportunity for learning will be in the classroom and so we encourage students
to attend class whenever possible.
All office hours will be held in the Seamans Lounge (lounge area on the first
floor of Building 33) 4-5pm every Wednesday. During these office hours, the faculty and TA will be
available on Skype. However, it is possible that we will be busy helping
students in the Lounge, and may not be able to respond to a Skype request.
Students can also set up appointments (in person or via Skype) with the
faculty and TA. Please send an email to the person you would like to schedule
an appointment with.
Homework will include:
- Required advance reading assignments from a set of notes available
on the course website and suggested reading from the course textbook. Due:
the class following that in which the assignment is given.
- Required advance answer of concept questions and attempted solution
of introductory-level exercises which are included in the notes as part
of the reading assignments. The exercises are designed to improve your
understanding of the material while you are reading. Due: the class
following that in which the assignment is given.
- Problem sets given most weeks, will consist of problems designed to
be more challenging and will include a combination of look-ahead and look-back
problems. Look-ahead problems will be based on material that we have not yet
discussed in class (though you will have had a reading assignment on the
material). Look-back problems will be based on material that we have
discussed in class. Due: on Fridays at 9:00am in class
Late homework submission will not be accepted.
While discussion of the homework and projects is encouraged among students,
the work submitted for grading must represent your understanding of the
subject matter. Significant help from other students or other sources should
be noted in writing (at the top of your assignment).
There will be two exams: an oral midterm and an oral final. Midterm exams
will be scheduled for March 20--23, i.e., during the week preceding spring
break. The final exam will be held during final exam week, May 21--25.
Individual times for the midterm will be scheduled 2--3 weeks prior based on
preferences from each student. Individual times for the final exam will be
determined within 3 weeks of the Institute's final exam schedule being
announced.
Each exam will be assigned a letter grade based on the standard MIT letter
grade descriptions.
Discussing any aspect of an oral exam (whether content or style) outside of
the examination room is strictly prohibited!
The subject total grade will be based on the numeric grades obtained in the
following three categories: Class Participation, Problem Sets and
Exams. The weighting of the individual numeric grades is as follows:
- Class Participation (20\%). Class participation will be
assessed daily on an individual basis at each table by the table
tutor. The assessment will be based on: evidence of advance reading,
attempt to solve look-ahead problems, proactive question posing and
active engagement with tutor, peers and rest of the course
instructors. Students are encouraged to provide any written evidence
(e.g. own derivations, drawings, answers to concept questions and
problems) that may help in participation assessment.
In order to provide participation opportunities for students
connecting remotely, students will be asked to provide a skype
userid so that they can be contacted by course staff during class
sessions to join a specific table group. It is expected that these
students participating remotely will engage at the same level as
those physically present.
It should be emphasized that attendance per se whether physical or
virtual will not be considered as part of the assessment.
- Problem Sets (20\%)
- Midterm exam (30\%)
- Final exam (30\%)
The final numeric grade will be converted into a final subject letter grade.
For the subject letter grade, we adhere to the MIT grading guidelines which
give the following description of the letter grades:
- Exceptionally good performance demonstrating a superior understanding of
the subject matter, a foundation of extensive knowledge, and a skillful use of
concepts and/or materials.
- Good performance demonstrating capacity to use the appropriate concepts,
a good understanding of the subject matter, and an ability to handle the
problems and materials encountered in the subject.
- Adequate performance demonstrating an adequate understanding of the
subject matter, an ability to handle relatively simple problems, and adequate
preparation for moving on to more advanced work in the field.
- Minimally acceptable performance demonstrating at least partial
familiarity with the subject matter and some capacity to deal with relatively
simple problems, but also demonstrating deficiencies serious enough to make it
inadvisable to proceed further in the field without additional work.
(BC)
Structural Analysis with Applications to Aerospace Structures
Bauchau, O. A., and J. I. Craig.
Springer, 2009. (Recommended)This is the main textbook of the class.
It is written by a former student of Prof. Dugundji who is a Professor at
Georgia Tech.
We encourage you to purchase this book. Its contents are also available at the
link above from the MIT network.
(TG)Theory of Elasticity Timoshenko, S. P., and J. N. Goodier.
McGraw-Hill Publishing Company, 3rd Edition, 1970.
(R)Theory and analysis of flight structures Rivello, R. M.
McGraw-Hill Publishing Company, 1969.
(M)An introduction to aircraft structural analysis Megson, T.
H. G. Butterworth-Heinemann/Elsevier, 4th Edition 2007.
(T)Theory of Elastic Stability Timoshenko, S. P., and J. M.
Gere. MacGraw-Hill Publishing, 1961.
(G)Mechanics of materials Gere, J. M., and S. P. Timoshenko
PWS Pub Co. 1997.
(Reddy)Energy Principles and Variational Methods in Applied
Mechanics Reddy, J. N. Wiley, 2nd Edition, 2002.