Study Guide - University of Pretoria

Study Guide Department of Mechanical and Aeronautical Engineering Structural Mechanics MSY 310

Lecturer: Dr Helen Inglis Date of last revision: 31 January 2020

Table of Contents

1 Introduction ................................................................................................................ 1

1.1 Welcome ......................................................................................................................... 1

1.2 Educational approach ...................................................................................................... 1

1.3 Learning activities ........................................................................................................... 1 1.3.1 Contact Time .................................................................................................................................... 1 1.3.2 Homework Assignments ................................................................................................................... 1 1.3.3 Practical ............................................................................................................................................ 1 1.3.4 Tutorial and Class Tests .................................................................................................................... 1

1.4 Responsibilities of the student ........................................................................................ 2

2 Administrative information ......................................................................................... 5

2.1 Contact details ................................................................................................................ 5

2.2 Timetable ........................................................................................................................ 5

2.3 Office Hours .................................................................................................................... 5

2.4 clickUP ............................................................................................................................ 5

2.5 Grievance procedures ...................................................................................................... 5

3 Study material and purchases ..................................................................................... 6

3.1 Prescribed textbooks ....................................................................................................... 6

3.2 Course Notes ................................................................................................................... 6

3.3 Class Notes ...................................................................................................................... 6

4 Rules, requirements and guidelines ............................................................................ 7

4.1 Departmental study guide ............................................................................................... 7

5 Module information .................................................................................................... 8

5.1 Purpose of the module .................................................................................................... 8

5.2 Learning presumed to be in place .................................................................................... 8 5.2.1 Prerequisite modules ....................................................................................................................... 8 5.2.2 Computer Literacy ............................................................................................................................ 8

6 Assessment ................................................................................................................. 9

6.1 Tests and Examination .................................................................................................... 9

6.2 Mark breakdown ........................................................................................................... 10

6.3 Assessment policy ......................................................................................................... 10 6.3.1 Practical .......................................................................................................................................... 10 6.3.2 Admission to the Exam ................................................................................................................... 10 6.3.3 Pass Requirements ......................................................................................................................... 10 6.3.4 Sick Test .......................................................................................................................................... 10

6.4 Plagiarism ..................................................................................................................... 10

7 Student support ........................................................................................................ 12

8 Addendum A: Support services ................................................................................. 13

© 2020 University of Pretoria

1

1 Introduction 1.1 Welcome

Structural mechanics is concerned with analysing the effect of external applied loads on structures. Applying the principles of Newtonian mechanics, the resistance of the material to these external loads results in internal reaction forces that cause deformation and displacement within the loaded material. In this course, we will analyse and understand the stresses and deformations that result from applied loading. We will consider different design and failure criteria, appropriate for each material. This understanding is necessary to design structures for safe and failure-free operation.

1.2 Educational approach

Lectures will be used to convey fundamental principles and to answer questions. It is expected that the student master the detail of the subject by self-study and practice. In order to achieve this, the homework problems are of great value. The focus is on understanding rather than on memorisation, which stimulates creative thinking and innovation skills in structural mechanics. It is therefore important to not only ask the question ‘How?’ but also ‘Why?’ Students are encouraged to be able to discern the important global aspects of a problem from the details. For this the underlying theory and principles are very important.

1.3 Learning activities

1.3.1 Contact Time The course runs through the 1st semester and there are 3 lectures and 1 two-hour tutorial per week for 12 weeks, as shown in the class schedule in Section 2.2. This is a 16-credit module requiring approximately 160 learning hours. Students should therefore be spending approximately eight hours per week working on the module besides the time spent in class. These hours could be spent preparing for class; reviewing class notes; working through the textbook; completing homeworks and projects.

1.3.2 Homework Assignments Regular homework assignments will be given to help guide students in their preparation. These homework assignments will not be assessed.

1.3.3 Practical The practical will consist of a laboratory session with application to structural mechanics. Students will hand in a report for assessment. The practical will contribute to the semester mark.

1.3.4 Tutorial and Class Tests Tutorial tests will be given to assess students’ progress. Occasional class tests may also be given. These will contribute to the semester mark.


2

1.4 Responsibilities of the student

There are 36 lectures during which the relevant principles will be conveyed. It is expected that students attend class regularly and be prepared at all times to participate in class discussions. Homework assignments will be given every Thursday, covering the material which has been taught that week. Students are expected to attempt the homework problems before the tutorial on Monday, and to come prepared to ask questions on aspects which they do not understand. Tutorials offer an opportunity for the students to discuss issues regarding structural mechanics with the lecturer, teaching assistants and classmates. The topics which will be covered in each

Week Contact session

date Theme Topic Preparation for Class /

Homework

L1 Tue 4 Feb Stress and strain Review concepts of stress and strain Notes: L01-L03 pp 1–3

L2 Wed 5 Feb Stress and strain 3D concepts of stress and

strain Notes: L01-L03 pp 5–7; L02

L3 Fri 7 Feb Stress and strain Constitutive relations Notes: L01-L03 pp 7–10

T1 Mon 10 Feb Tutorial Homework 1

L4 Tue 11 Feb Stress and strain 1D, 2D, plane stress, plane

strain Notes: L04 GG: §7.2, §7.7

L5 Wed 12 Feb Stress and strain Strain energy GG: §2.7, §7.5

L6 Thu 13 Feb

Stress and strain transformations

Eigenvalue concept, 3D Mohr’s circle Notes: L05-L08 pp 10-15


L7 Tue 18 Feb

Stress and strain transformations

2D Mohr’s circle, transformation equations

Notes: L05-L08 pp 1–9 & 15-16; L07 GG: §7.4

L8 Wed 19 Feb

Experimental strain measurements

Strain gauges Notes: L05-L08 pp 17-18 GG: §7.7

L9 Thu 20 Feb Pressure vessels Thin walled pressure vessel GG: §8.2


L10 Tue 25 Feb Pressure vessels Thin walled pressure vessel GG: §8.3

L11 Wed 26 Feb Simple Beams

Beam BC’s; Shear Force and Bending Moment diagrams; Macaulay method

GG: §4.3-§4.5 Notes: L11

L12 Thu 27 Feb Simple Beams Review bending stress for

simple beam GG: §5.1-§5.6

T4 Mon 2 Mar Tutorial Homework 4


3



Homework

L13 Tue 3 Mar Simple Beams Review shear stress for

simple beam GG: §5.8-§5.11

L14 Wed 4 Mar

Deflection in beams

Derivation of deflection equations GG: §9.1-§9.4

L15 Thu 5 Mar

Deflection in beams

Slope and deflection; Theory of superposition; Strain energy of bending

GG: §9.5; §9.8

TEST WEEK 1

T5 Mon 16 Mar Tutorial Homework 5

L16 Tue 17 Mar

Deflection in beams Castigliano’s Theorem GG: §9.9

L17 Wed 18 Mar

Statically indeterminate beams

Solution strategies for multiple supports GG: §10.1-§10.3

L18 Thu 19 Mar

Statically indeterminate beams

Solution using superposition GG: §10.4

UNIVERSITY HOLIDAY

L19 Wed 1 Apr Advanced beams Composite beam GG: §6.2-§6.3

L20 Thu 2 Apr Advanced beams Non-aligned load GG: §6.4

T6 Mon 6 Apr Tutorial Homeworks 6a and 6b

L21 Tue 7 Apr Advanced beams Unsymmetric beams GG: §6.5

L22 Wed 8 Apr Advanced beams Shear flow; shear centre GG: §6.6-§6.9

L23 Thu 9 Apr Advanced beams Torsion of thin-walled open sections; Torsion of thin tubes

GG: §3.10-§3.11

L24 Tue 14 Apr Advanced beams Code design

L25 Wed 15 Apr

Buckling instability Buckling and stability GG: §11.1-§11.2

L26 Thu 16 Apr

Buckling instability

Derivations for different end conditions GG: §11.3-§11.4

TEST WEEK 2

L27 Tue 28 Apr

Buckling instability

Eccentric load; secant formula; inelastic buckling GG: §11.5-§11.8

T7 Wed 29 Apr * Tutorial Homeworks 7a and 7b

T8 Mon 4 May Tutorial Homework 8

L28 Tue 5 May

Elastoplastic analysis

Uniaxial yield; Plastic collapse of beams GG: §2.11-§2.12; §6.10

L29 Wed 6 May

Elastoplastic analysis Plastic collapse of beams GG: §6.10


4



Homework

L30 Thu 7 May Yield criteria Triaxial yield – mechanism;

Tresca Shigley: §5.4


L31 Tue 12 May Yield criteria Von Mises; comparison;

Coulomb-Mohr Shigley: §5.5; §5.6

L32 Wed 13 May

Fracture Mechanics Stress intensity factor Shigley Ch 5; Notes

L33 Thu 14 May

Fracture Mechanics

Stress fields around crack tip Shigley Ch 5; Notes


L34 Tue 19 May

Fracture Mechanics

Geometry factors; Ductile-brittle transitions Notes

L35 Wed 20 May Fatigue Review; Fatigue crack

propagation Notes

L36 Thu 21 May Fatigue Fatigue crack propagation Notes


* Wed 29 Apr follows a Monday timetable


5

2 Administrative information The course will be presented by Dr Helen Inglis.

2.1 Contact details

Office: Engineering 1 - Room 10-21 E-mail: [email protected] The preferred contact method is email, which will be answered within one business day. Please remember that emails are a form of professional communication. In the subject line, include the course code and a descriptive subject. Use appropriate forms of address. Please include your full name and student number.

2.2 Timetable Contact session Day Time Venue Lecture 1 Tuesday 9:30 – 10:20 Eng III-6 Lecture 2 Wednesday 11:30 – 12:20 Eng III-1 Lecture 3 Thursday 7:30 – 8:20 Eng III-6 Tutorial Monday 8:30 – 10:20 Eng I, 1-1, 1-4

2.3 Office Hours

Office hours will be arranged in the first week of classes to be convenient for as many people as possible. If additional consultation is necessary, please schedule via email.

2.4 clickUP

A module for Structural Mechanics (MSY310) will be available on clickUP. All correspondence and administration will be handled electronically via clickUP. Students are encouraged to use clickUP continuously through the semester. Notes and assignments will be posted on the module website and it is expected that students download the relevant material before lectures and tutorials.

2.5 Grievance procedures

All grievances must be submitted in writing with specifics of the incident or the nature of the complaint. It is imperative that you follow the procedure outlined below in order to resolve your issues:

1. Consult the lecturer concerned about your grievances/concerns. If the matter has not been resolved, 2. consult the class representative (The primary function of the Class Representative is to serve

as a two-way communication channel between the class and the lecturer). If the matter has not been resolved, 3. consult the module co-ordinator (large modules with multiple lecturers) If the matter has not been resolved, 4. consult the Head of Department If the matter has still not been resolved, 5. consult with the Dean of the Faculty


6

3 Study material and purchases 3.1 Prescribed textbooks

There are two prescribed textbooks in this course: Goodno, BJ and Gere, JM, “Mechanics of Materials”, 9th SI edition, Cengage Learning, 2018. ISBN 978-1-337-09335-4. (Students who have a copy of the 8th edition of the textbook instead are welcome to use it, but are responsible for aligning page numbers: Gere, JM and Goodno, BJ, “Mechanics of Materials”, 8th SI edition, Cengage Learning, 2013. ISBN 978-1-111-57774-2.) Budynas, RG and Nesbitt, KJ, “Shigley’s Mechanical Engineering Design”, 10th SI edition, McGraw-Hill, 2014.

3.2 Course Notes

Occasional course notes will be published on clickUP where necessary. It is the student’s responsibility to download these notes.

3.3 Class Notes

The primary notes for the class will be presented in the classroom, via the chalkboard. Students are responsible for attending class, taking notes, and for following up with the lecturer if there is anything they do not understand. Students who miss a class are responsible for getting notes from a classmate. Office hours will not be used to catch up this material.


7

4 Rules, requirements and guidelines 4.1 Departmental study guide

This study guide is a crucial part of the general study guide of the Department. In the study guide of the Department, information is given on the mission and vision of the department, general administration and regulations (professionalism and integrity, course related information and formal communication, workshop use and safety, plagiarism, class representative duties, sick test and sick exam guidelines, vacation work, appeal process and adjustment of marks, university regulations, frequently asked questions), ECSA outcomes and ECSA graduate attributes, ECSA knowledge areas, CDIO, new curriculum and assessment of cognitive levels. It is expected that you are very familiar with the content of the Departmental Study Guide. It is available in English and Afrikaans on the Department’s website. Eng: https://www.up.ac.za/media/shared/120/Noticeboard/2020/departmental-studyguide-eng-2020_version21jan2020-002.zp185016.pdf

Afr: https://www.up.ac.za/media/shared/120/Noticeboard/2020/departementele-studiegids-afr-2020_weergawe21-jan2020-002.zp185015.pdf

Take note of the specific instructions in the above study guide on:

a. Safety b. Plagiarism c. What to do if you were sick (very important) d. Appeal process on the adjustment of marks


8

5 Module information 5.1 Purpose of the module

The effective application of structural mechanics is somehow or another relevant to most engineering disciplines. Structural Mechanics is concerned with analysing the effects of applied loads on and in bodies. In this module the student will primarily study the following:

• The stress and strain relationships in a material. • The mechanics of various structural members under applied loading. • The failure and fracture of materials. • This theory in turn equips the student to design:

o Against displacement limits; o Against stress limits; o For fracture strength, and o With consideration of material properties.

5.2 Learning presumed to be in place

5.2.1 Prerequisite modules Machine design (MOW 227), Differential Equations (WTW 256). Structural Mechanics (MSY310) is the extension of these courses. The internal behaviour (stress and strain states) of materials under external loading will be analysed using mathematical and physical principles.

5.2.2 Computer Literacy Since some of the problems in this module are calculation intensive, students will benefit considerably from computer access. A working knowledge of Python or other programming language is required and proficiency with a spreadsheet will also be valuable. Access to a computer and the software mentioned can be obtained from the faculty’s computer laboratory.


9

6 Assessment 6.1 Tests and Examination

Two semester tests will be written during the semester. The duration of each test will be 90 minutes while the examination will be 180 minutes. No study material or notes will be allowed in tests and exams. No alphanumerical programmable calculators will be allowed in the tests and exams. The necessary information and formulas for the exam will be given during the tests and exam. This is an exit level module for ECSA Graduate Attribute 1: Problem Solving. Learning outcome: Demonstrate competence to identify, assess, formulate and solve convergent and divergent engineering problems creatively and innovatively. Associated Assessment Criteria: The candidate applies in a number of varied instances, a systematic problem solving method including:

1. Analyses and defines the problem, identifies the criteria for an acceptable solution; 2. Identifies necessary information and applicable engineering and other knowledge and skills; 3. Generates and formulates possible approaches to solution of problem; 4. Models and analyses possible solution(s); 5. Evaluates possible solutions and selects best solution; 6. Formulates and presents the solution in an appropriate form.

Range Statement: Problems requires identification and analysis. Some cases occur in unfamiliar contexts. Problems are both concrete and abstract and may involve uncertainty. Solutions are based on theory and evidence, together with judgement where necessary. A number of problems in both semester tests and the final examination will be assessed with a rubric based on the ECSA problem solving requirement. In order for a student to pass the module, it is necessary that they attain a mark of at least 50% on this component of the assessment. The rubric categories are shown in the following table. For each question assessed using the rubric, appropriate weightings are given for each category.

Assessment Q2 weight Q2 score Analyse and define the problem, identify the criteria for an acceptable solution. *Applied loading *Boundary conditions *FBD *Reaction forces *Internal forces.

XX

Identify necessary information and applicable engineering and other knowledge and skills. *Material properties *Knowns/unknowns *Assumptions

XX

Generate and formulate possible approach(es) to solve the problem. Identify and setup relevant criteria and analyses e.g. max stress; max deflection; yield; buckling; fracture.

XX

Model and analyse possible solution(s). Calculate stress, strain, deflection, etc; as relevant. XX

Evaluate possible solutions and select best solution. Justify and explain choice. XX

Formulate and present the solution in an appropriate form. Correct symbols and units. XX

TOTAL 10


10

6.2 Mark breakdown

The Final mark will be calculated as follows: Exam mark 50% Class mark 50% TOTAL: 100% Class mark breakdown: Practical 10% Tutorial and class tests 20% Semester Test 1 35% Semester Test 2 35%

6.3 Assessment policy

6.3.1 Practical The practical will consist of a laboratory session with application to structural mechanics. A mark for the practical of at least 50% is required to be admitted to the exam.

6.3.2 Admission to the Exam A student will be admitted to the exam if a semester mark of at least 40% has been achieved, and a practical mark of at least 50% has been achieved.

6.3.3 Pass Requirements Passing requires a final mark of at least 50%, and a subminimum of 50% on the ECSA problem solving rubric in the final examination.

6.3.4 Sick Test A sick test will be granted to students who qualify for such a test. It is the responsibility of the student to apply for such test according to the procedure stipulated in the departmental study guide. Only one sick test, on all the work covered up to the lecture before the sick test, will be given. The test will be written after the second semester test.

6.4 Plagiarism

Plagiarism is a serious form of academic misconduct. It involves both appropriating someone else’s work and passing it off as one’s own work afterwards. Thus, you commit plagiarism when you present someone else's written or creative work (words, images, ideas, opinions, discoveries, artwork, music, recordings, computer-generated work, etc.) as your own. Only hand in your own original work. Indicate precisely and accurately when you have used information provided by someone else. Referencing must be done in accordance with a recognised system. Indicate whether you have downloaded information from the Internet. For more details visit the following websites: https://www.up.ac.za/en/about-up/article/2013215/why-learn-about-plagiarism. Please download a QR code reader on your cellphone. To download a QR code reader open your mobile app store (App Store, Google Play or Windows Marketplace) and search for QR code readers.


11

Why learn about plagiarism? What is plagiarism? How do I avoid

plagiarism? Overstepping the

mark


12

7 Student support The University of Pretoria supports you in various ways free of charge. For academic support contact the tutors allocated to the module (see section 2.1), and/or the Faculty Student Advisor (see section 2.1).

Faculty student advisors

Academic support Goal setting & motivation Adjustment to university life Test/Exam preparation Stress management Career exploration

Individual consultations and workshops about - time management - study methods

FLY@UP: The Finish Line is Yours

• Think carefully before dropping modules (after the closing date for amendments or cancellation of modules).

• Make responsible choices with your time and work consistently.

• Aim for a good semester mark. Don’t rely on the examination to pass.

www.up.ac.za/fly@up email: [email protected]

For e-learning support

• Report a problem you experience to the Student Help Desk. • Approach the assistants at the help desks (adjacent to the Student Computer Laboratories in

IT Building, NW2, CBT, etc). • Visit the open labs in the Informatorium Building to report problems at the offices of the

Student Help Desk. • Call 012 420 3837. • Email [email protected]

Safety in the evening: Green Route

• From 18:00 till 06:00 Security Officers are available to escort you (on foot) to and from your residence or campus anywhere east of the Hatfield campus through to the LC de Villiers terrain.

• Departure point is at the ABSA ATM next to the Merensky Library. • Phone the Operational Management Centre if you need a Security Officer to accompany you

from your residence to campus. For more support services see Addendum A


13

8 Addendum A: Support services Please download a QR code reader on your cell phone. To download a QR code reader open your mobile app store (App Store, Google Play or Windows Marketplace) and search for QR code readers.

Student Counselling Unit

Provides counselling and therapeutic support to students. 012 420 2333

Student Health Services

Promotes and assists students with health and wellness.

012 420 5233 012 420 3423

The Careers Office

Provides support for UP students and graduates as they prepare for their careers.

[email protected] 012 420 2315

Department of Security Services

24-hour Operational Management Centre 24-hour Operational Manager cell Crisis Line

012 420-2310 012 420-2760 083 654 0476 0800 006 428

Department of Student Affairs

Enquiries concerning studies, accommodation, food, funds, social activities and personal problems.

012 420 2371/4001 Roosmaryn Building, Hatfield campus

Centre for Sexualities, AIDS and Gender

Identifies and provides training of student peer counsellors. 012 420 4391

Disability Unit Ensure an integrated and inclusive learning experience for students with disabilities.

012 420 2064

Fees and funding

http://www.up.ac.za/enquiry www.up.ac.za/fees-and-funding 012 420 3111

IT Helpdesk For student IT related queries 012 420 3051 [email protected]

Study Guide - University of Pretoria

Documents

Transcript of Study Guide - University of Pretoria