COURSE UNIT TITLE

: INTRODUCTION TO FRACTURE MECHANICS

DEGREE PROGRAMMES

Description of Individual Course Units

Course Unit Code Course Unit Title Type Of Course D U L ECTS
MAK 4051 INTRODUCTION TO FRACTURE MECHANICS ELECTIVE 3 0 0 4

Offered By

Mechanical Engineering

Level of Course Unit

First Cycle Programmes (Bachelor's Degree)

Course Coordinator

PROFESSOR DOCTOR EVREN MELTEM TOYGAR

Offered to

Mechanical Engineering
Mechanical Engineering

Course Objective

The aim of the couse is to solve the engineering problems under the consideration of the fundamental concepts (fracture, and basic modes of loading involving different crack surface displacement, fracture types) of LEFM (linear elastic fracture mechanics) and EPFM( elastic-plastic fracture mechanics), by using mathematical and physical knowledge. Moreover, to calculate the mechanical behaviour of the body including cracks, applied stress, the stress intensity factor at the crack tip, crack length, and fracture toughness parameters are the goals of the course. The other object is to find the solutions for the real problems by examining the faults such as cracks, notches and holes which cause the stress concentration and deformation and crack, fatique, creep and stres corosion crack

Learning Outcomes of the Course Unit

1   To be informed of the bacis concepts in LEFM (linear elastic fracture mechanics) and EPFM( elastic-plastic fracture mechanics) by considering failure, fracture types and idealised fracture.
2   To quote the mathematical modeling of the engineering materials including crack, notch or ext. in the stuctures and the coherence with nowadays problems.
3   To obtain the parameters used in desing and dimensions,
4   To have an information about LEFM and EPFM , and to give the calculation of the parameters that is used in engineering structures and the types of application,
5   To make the study deals with the systems subjected to fatique, static and dynamic loading.

Mode of Delivery

Face -to- Face

Prerequisites and Co-requisites

None

Recomended Optional Programme Components

None

Course Contents

Week Subject Description
1 Introduction: History of Fracture Mechanics, Fundamental concepts and equations, The definition of failure mechanisms
2 LEFM (linear elastic fracture mechanics) : Elastic stress field, the relationships between the stress and the strain, the stress intensity factor for Mod I, Mod II and Mod III, the fracture toughness parameter
3 Energy approach: Griffith Energy Approach, Irwin modification under the consideration of Griffith Energy theorem, The relationship between the G ve KI
4 The plastic zone at crack tip: The radius of plastic zone, plastic zone through thickness of the sample.
5 Mathematical modeling of LEFM: Plane elasticity, Cartesian coordinate, Polar coord., the analysis of crack propagation instability, the stress analysis at the crack tip, Westergaard Stress function
6 Mathematical modeling of LEFM: Plane elasticity, Cartesian coordinate, Polar coord., the analysis of crack propagation instability, the stress analysis at the crack tip, Westergaard Stress function
7 Midterm 1
8 Elastic/Plastic Fracture Mechanics(EPFM): J Integral, crack opening displacement
9 Mathematical modeling of EPFM: to identify the crack tip opening displacement with yield modeling, J Integral, nonlinear energy release rate, singularity function
10 Mathematical modeling of EPFM: to identify the crack tip opening displacement with yield modeling, J Integral, nonlinear energy release rate, singularity function
11 Linear Elastic Fracture Mechanics Test: Plane strain- fracture toughness Standard test method of metallic materials, samples and dimensions, preparation of the samples, load-displacement terms and the obtaining of KIC parameters
12 Midterm 2
13 Fatique Failure: Stress life, Strain-life approach, fatique crack propagation, fatique diagram, fatique plastic zone, fatique applications in engineering structure
14 The Application of Fracture Mechanics to Engineering Structures : LEFM Applications, ASME Reference curves, Crack Mouth Opening Displacement curvesThe Application of Fracture Mechanics to Engineering Structures : LEFM Applications, ASME Reference curves, Crack Mouth Opening Displacement curves

Recomended or Required Reading

T. L. Anderson, "Fracture Mechanics: Fundamentals and Applications" (1995) CRC Press.
Richard W.Hertzberg, Deformation and Fracture Mechanics Of Engineering Materials.
Dowling, "Mechanical Behavior of Materials"
Broek, Elementary Engineering Fracture Mechanics
Ağah Uğuz, Kırılma Mekaniğine Giriş

Planned Learning Activities and Teaching Methods

The course is taught in a lecture, class presentation and discussion format. All class members are expected to attend and both the lecture and take part in the discussion sessions. Besides the taught lecture, group presentations are to be prepared by the groups assigned for that week and presented to open a discussion session..

Assessment Methods

SORTING NUMBER SHORT CODE LONG CODE FORMULA
1 MTE1 MIDTERM EXAM 1
2 MTE2 MIDTERM EXAM 2
3 ASG ASSIGNMENT
4 PRC PRACTICE
5 FIN FINAL EXAM
6 FCG FINAL COURSE GRADE MTE1 * 0.175 + MTE2 * 0.175 + ASG * 0.075 + PRC * 0.075 + FIN * 0.50
7 RST RESIT
8 FCGR FINAL COURSE GRADE (RESIT) MTE1 * 0.175 + MTE2 * 0.175 + ASG * 0.075 + PRC * 0.075 + RST * 0.50


*** Resit Exam is Not Administered in Institutions Where Resit is not Applicable.

Further Notes About Assessment Methods

None

Assessment Criteria

There will be 2 miterms, averaged out grades for which will be 35 % of the overall success of the students. Homework will be 7.5% and the project will be 7.5% of the success of the
student. Final exam will be 50 % of the resulting grade.

Language of Instruction

Turkish

Course Policies and Rules

Optional

Contact Details for the Lecturer(s)

Doç.Dr.M.Evren Toygar, evren.toygar@deu.edu.tr,
Dokuz Eylül University, Department of Mechanical Engineering,
Phone: 0 232 301 92 25

Office Hours

To be announced.

Work Placement(s)

None

Workload Calculation

Activities Number Time (hours) Total Work Load (hours)
Lectures 12 3 36
Preparations before/after weekly lectures 12 2 24
Preparation for midterm exam 2 5 10
Preparation for final exam 1 10 10
Preparing assignments 3 2 6
Design Project 1 9 9
Final 1 2 2
Midterm 2 2 4
TOTAL WORKLOAD (hours) 101

Contribution of Learning Outcomes to Programme Outcomes

PO/LOPO.1PO.2PO.3PO.4PO.5PO.6PO.7PO.8PO.9PO.10PO.11
LO.15433545
LO.25545445
LO.3554543
LO.4553455453
LO.5554455443

CONTACT INFORMATION
Dokuz Eylül Üniversitesi Cumhuriyet Bulvarı No: 144 35210 Alsancak / İZMİR
Phone: +90(232) 412 12 12 - Fax: +90 (232) 464 81 35

Copyright 2015 DEÜ. BİD

HOME / ABOUT US / DEGREE PROGRAMMES / GENERAL INFORMATION FOR STUDENTS / INTERNATIONAL RELATIONS