CIV-E4100 - Stability of Structures D, Lecture, 28.2.2022-17.4.2022
Kurssiasetusten perusteella kurssi on päättynyt 17.04.2022 Etsi kursseja: CIV-E4100
Osion kuvaus
-
Course name: Stability of Structures
TODAY INFO 22/2/2022:
The information: The course (lectures and exercise-cessions) and examination will be organised as contact teaching.
Schedule for exercise (homework guided sessions):
Day
Date
Time
Method
Wednesday
02/03/2022
16:15-18
Contact Teaching
Friday
04/03/2022
16:15-18
Contact Teaching
Wednesday
09/03/2022
16:15-18
Contact Teaching
Friday
11/03/2022
16:15-18
Contact Teaching
Wednesday
16/03/2022
16:15-18
Contact Teaching
Friday
18/03/2022
16:15-18
Contact Teaching
Wednesday
23/03/2022
16:15-18
Contact Teaching
Thursday
24/03/2022
16:15-18
Contact Teaching
Wednesday
30/03/2022
16:15-18
Contact Teaching
Friday
01/04/2022
16:15-18
Contact Teaching
Wednesday
06/04/2022
16:15-18
Contact Teaching
Friday
08/04/2022
16:15-18
Contact Teaching
Thursday
14/04/2022
16:15-18
Contact Teaching
Friday
15/04/2022
16:15-18
Online Teaching
******************************************************In short: In this course, we study the elastic stability structures.
The primary question, even an engineering design question, is under which conditions an equilibrium becomes unstable.
The content is conceptually very short having only three fundamental concepts to study: 1) equilibrium, 2) its stability properties and 3) sensitivity of such equilibrium to imperfections
Many applications of structural stability of typical structural elements commonly used in civil engineering will be studied.
---------
This course have a very dense and demanding content and six weeks is short.
The weekly homework topics and the associated readings will be the 'GPS' guiding the student through the necessary material to learn.
The lectures will concentrate on the key topics and on the invariant fundaments while illustrating all that through examples.
Therefore, first we address the physics (mechanics) of instability phenomena (observation) then we try to find the minimum number of degrees of freedom to describe mathematically the problem using first principles (posing or setting the problem) and thirdly, we try to find practical solutions of importance for understanding and doing quality structural design.
We will not hide the phenomena behind unnecessary complexe mathematics: First comes the physics then the mathematics follows as an instrument of thoughts (ajattekuväline) to obtain handels which gives us the buckling equations. (our mathematics will be the theorem: at a STABLE equilibrium the total potential energy has a local minimum for a conservative system) , and the universal virtual work principle for both conservative and non-conservative systems.The student is encouraged to prepare for lectures and homework cessions, at least, by doing the reading assignments on time from references [1] and [2], below. You are working for yourself. Doing actively homework assignments will guide you through te readings and help you to deepen and consolidate what you have learnt.
Please, do not concentrate to much on subjective workload-concept only since “workload” is just the amount of personal time each one invests in studying new skills and knowledge. Think that you are training to be among the best ... engineers. "What we can gain?" is the correct question not the price in hours. (of course, the work should be doable in six-seven week… and it is)
D.B, 2021
Teacher
Djebar BAROUDI, DR.h. 229Content
- Flexural buckling (nurjahdus)
- Lateral-torsional buckling (kiepahdus)
- Torsional buckling (vääntönurjahdus)
- Buckling of thin plates (levyjen lommahdus)
- Buckling of shells (kuorien lommahdus)
Literature
- CHAI H. YOO & SUNG C. LE . STABILITY OF STRUCTURES - Principles and Applications, 2011 Elsevier e-textbook (our course main textbook)
- Lecturer own pdf-material ---> weeks 1 ... 6 (will be provided weekly)
- Solutions of homewok
Additinal reading: (not compulsory)
- S.P. Timoshenko & J.M. Gere. Theory of Elastic Stability. 2nd Ed., 1985. (Classical textbook)
- Juha Paavola. Structural Stability. Lecture note - 2018 (pdf in MyCourses) . (This is a 'must-read' for those interrested in general and systematic energetic approach for elastic stability. .. by Emer. prof. J. Paavola)
- Markku TUOMALA's Lectures notes: Elastic Stability of structures (lecture notes in Finnish: Rakenteiden stabiilisuusteoria, luentomoniste).
(A masterpiece by Emer.prof. M. Tuomala following the long Finnish tradition of mechanics masters to cite some of them like A. Ylinen, M. Mikkola, P. Jumppanen, E-M. Salonen, J. Aalto, J. Paavola, R. Kouhia, T. Salmi and many others. This material provides theorethical basis together with plenty of solved application examples: https://mycourses.aalto.fi/pluginfile.php/1518323/course/section/182948/Book_profTuomala_rakenteiden_stabiilius%20-%20Copy.pdf)
- Lecture's own material: Stability of structures (D. Baroudi)
- [they are in given in ...]
A short review article: Fundaments of stability of structures with examples:The course:
This course is rich in various applications of structural stability. Despite this variety of applications, it is conceptually short having only three fundamental concepts to study: 1) equilibrium, 2) its stability properties and 3) sensitivity of such equilibrium to imperfections
Please invest actively time wisely to achieve these intended learning goals by doing responsibly the weekly given readings together with the homework. Participating actively to lectures will, for sure, shorten the learning process by minimising unnecessary dissipation.
Bellow the learning outcomes are recalled in details:
- Recognising the key importance of stability of structures as a primary requirement for
engineering load-bearing structures
- Understand thetheoretical foundations of the concept of Equilibrium and Stability of an
equilibrium
- Understand the meaning of equilibrium paths and post-buckling
- Understand the physics and mathematics of equilibrium transition from stable to unstable
- Ability to apply the energy-based stability analysis
- knows how to address the effect of initial imperfections on stability behaviour
- Ability to systematically apply the above fundamental energy concept to study the stability of various structures of importance of Civil Engineering, for instance, frame structures, warping torsion and Saint-Venant torsion of thin-walled members, plane buckling of plane frames and arches, torsional and lateral buckling of thin-walled members and buckling of plates and cylindrical shells
General
- Teacher: Djebar Baroudi, Dr.,
- Language: English - Finnish terminology will be also provided during the lectures
- Credits: 5 cr (op)
Teaching methods
- Lectures: 2h x (2 x week) := 4h/week – contact teaching – lecturing and demonstration with
physical and computer models
- Guided exercises/homework solving: 2h x (3 x week) – contact teaching – with the re-
sponsible teacher and an assistant from the industry (a professional)
- Self-studies in small groups or alone: at least 2h/day x6weeks x7days = 84 h – not Contact
teaching: preparing, doing the reading assignments, assimilating the course subjects and
given readings
Assignments + doing the homework outside the guiding hours- Examination: 3x3h – three times during the academic year– student personal performance in a written examination
- Grade 0-1, 0 := fail, 1-5 := pass
ACTIONS AND WORKLOADS
- Independent studying 50%: (reading and preparation 26%, home assignments 27%),
- Contact teaching 50% - covers the smaller complement (lectures 22%, exercise sessions
26%, examination 2%).
For instance, ~nominal hours (total 132) should guarantee for a student with average pre-requi-
sites (grade 3, good) middle range learning outcomes (with the average grade 3, good).-
Reading assignments and lectures material 2020] Kansio