EN31 Mechanics of Solids and Structures

EN31: Mechanics of Solids and Structures

General Information
Homework Assignments 2009 (Solutions)	Sample Homework Assignments 2008
Exams	Sample Homework Solutions 2008
Laboratory Information: Lab1 Lab2 Error Analysis	Sample Midterm Exam (Solutions)
Design Project	Sample Final Exam (Solutions)

Announcements

20/11/2009: New! Homework #10 is now posted. Note that HW#10 due on Monday, Nov. 30.
20/11/2009: New! Homework #9 Solution is now posted.
19/11/2009: Due date of Lab 2 report is postponed to Wednesday, Nov. 25.
13/11/2009: Homework #9 is now posted.
13/11/2009: Homework #8 Solution is now posted.
13/11/2009: Design Description is now posted.
13/11/2009: Design Project Lecture is now posted.
12/11/2009: PDF file of Homework #8 posted early has a typo: in Problem 7.60, " tensile stress is equal to or less than 60MPa " should be " in-plane shearing stress is equal to or less than 150MPa ". The corrected PDF file of Homework #8 is now posted.
07/11/2009: We will start planning on the final design project for the course. There will be a kick-off lecture on Friday Nov. 13. It is important that everyone attend this lecture. Prof. Gao will discuss the organization, objective and project evaluations and answer any questions.
07/11/2009: (1) If you have not done so, please sign up for Lab 2 (sign-up sheet posted on the door of BH 610. The time slots have been arranged from Tuesday (Nov. 10) to Friday (Nov. 13); (2) The report for Lab 2 will be due on Friday, Nov. 20.
06/11/2009: Homework #8 is now posted.
06/11/2009: Homework #7 Solution is now posted.
30/10/2009: Homework #7 is now posted.
28/10/2009: Midterm Solution is now posted.
25/10/2009: Midterm is open-book and open-note. Allow to use calculators, class-notes and homework solutions. The exam will cover everything up to HW#6.
23/10/2009: Homework #6 Solution is now posted.
21/10/2009: There seem to be a lot of questions about the error analysis in your lab 1 report due to some inconsistencies in the handouts (some from previous years). We have decided to adopt the following uniform rule: unless more precise information is known (from the instruments used in the lab or TAs) about a particular error in the measurement, we shall assume all parameters are known within 1% uncertainty.
21/10/2009: A midterm review lecture will be held on Monday, October 26. Prof. Gao will review some concepts and typical midterm problems from previous years.
21/10/2009: Lab 1 report due date is extended to next Monday (October, 26).
21/10/2009: Here are two additional issues regarding the lab:
                  (1) The load sensitivity given in the handout is off by a factor of 10 compared to what was actually used this year. Please check that the maximum load applied on the sample is around 4 kN, which would correspond to a load sensitivity ratio of 1 kN/volt, instead of 10 kN/volt.
                  (2) Some of you have reported that the ratio of the two strains in the torsion test is not -1. While the cause for this error has not been identified, please just use Equation (7) in your report to evaluate the shear modulus, noting that Equation (6) may not be satisfied by your data.
                   Equation (6): e_45°=-e₁₃₅_°=g/2
               Equation (7): g=e_45°-e_135°
21/10/2009: Due to the misunderstanding of experimental equipment setting, the channels of the strain gages for the tension test should be corrected:
(1) The channel for the extensional strain gage should be #105;
(2) The channel for the lateral strain gage should be #106.
16/10/2009: Homework #6 is now posted
16/10/2009: Homework #5 Solution is now posted.
14/10/2009: Every student need to submit an individual lab report.
09/10/2009: Homework #5 is now posted.
09/10/2009: Homework #4 Solution is now posted.
05/10/2009: TA (Glareh Azadi) office on Mondays is updated as " 102 B&H Basement (Prince Lab) ".
03/10/2009: PDF file of Homework #4 posted early has a typo: in Problem 2.87, " G=120MPa " should be " G=12MPa ". The corrected PDF file of Homework #4 is now posted.
02/10/2009: Homework #4 is now posted.
02/10/2009: Homework #3 Solution is now posted.
02/10/2009: Information for Midterm: in class, open book/note on Wednesday, October 28. You can bring the textbook and any material distributed to the class, e.g. lecture slides/notes, homework solutions.
02/10/2009: Lab 1 sign-up sheet posted on the door of BH 610. Lab 1 due on October 23 (on the bin outside BH 610).
30/09/2009: Some typos are corrected here: (1) In last line of Section 2 of handout for Lab 1, " the slop of T versus (pr³/2)r " should be " (pr³/2)g ";
(2) In Problem 2.50 of textbook, " a_s=11.7×10^-6/°F " should be " a_s=11.7×10^-6/°C ".
30/09/2009: Lab1 Information is now posted.
25/09/2009: Homework #3 is now posted.
25/09/2009: Homework #2 Solution is now posted.
24/09/2009: PDF file of Homework #2 is now uploaded for convenience.
18/09/2009: Homework #1 Solution is now posted.
18/09/2009: Homework #2 is now posted.
11/09/2009: TA office hours is now announced.
11/09/2009: Homework #1 is now posted.
09/09/2009: Welcome to class.

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