The engineer dedicated to the design of structures and mechanical elements must own an important theoretical and practical knowledge. In particular, he should be able to explain the relationship between a particular structural member with the stresses to which it may be subjected, either in the form of applied forces, temperature variations, support displacements, etc., and the stresses and strains originated in the structure, all of which constitute the primary object of the "Elasticity and Strength of Materials". Among the different types of structures that could be considered, the course focuses on the analysis of structures formed by prismatic bars.

The content of the course is divided into two distinct blocks. After a first subject in which the student is introduced into the behavior of deformable solids and the concept of structure, in the following four topics the basics of the Theory of Elasticity are presented: stresses, strains, constitutive laws and elastic problem resolution, with particular attention to the problems of two-dimensional elasticity and a brief presentation of the most relevant experimental methods to obtain stresses and strains. This first block is concluded with a theme, theories of failure, which serves as a transition between the field of Elasticity and the following topics belonging more specifically to the Strength of Materials.

In the first topic of the second block, after describing the different types of structures formed by prismatic bars, the analysis of section forces and moments is addressed in these elements. A theme is dedicated to the analysis of simple lattices subjected to axial forces. In the last two themes the stresses and strains caused in pure bending and simple bending are studied, and this knowledge is applied to the resolution of isostatic structures.

This course is part of the curricular line of Mechanical Engineering and, therefore, is based on the subjects of 2nd course "Mechanics" and "Applied Mechanics" whose knowledge and mastery are essential to understand the behavior of structures and other mechanical parts considered as deformable solids. Obviously, the student should also have a good grasp of the fundamental concepts of "Algebra" and "Calculus" studied in the first year. Another link can also be found with another subject taught in the third year, "Theory of Mechanisms and Mechanical Vibrations", a discipline that helps determine the forces undergone by the elements of a mechanism, and from which stresses and strains can be obtained by means of the "Elasticity and Strength of Materials". In this way a proper design ensuring system integrity can be obtained.

The knowledge acquired in this subject also form the basis of other mechanical-type subjects of the fourth year such as "Theory of Structures and Construction", where new methods are shown in the calculation of structures formed by prismatic bars. It is also evident the relationship with the subjects "Theory of Machines" and "Machine Elements", where it is essential to obtain stresses and strains and to apply the corresponding theories of failure. Finally, the "Elasticity and Strength of Materials" is also basic for some subjects included in several Master courses: in the "Master in Mechanical Engineering" (a continuation of the Degree in Mechanical Engineering) and in the "Master in Industrial Engineering" (a continuation of the Degree in Industrial Technology Engineering).

The competence of the subject, for the common module of the Industrial Branch, and reflected in the memory of the degree is:

- Knowledge and use of the principles of strength of materials.

As a result of learning it is expected that the students are able to:

- Acquire the basic knowledge governing the Theory of Elasticity, fundamental for analyzing the behavior of deformable solids and therefore for the analysis of Strength of Materials.

- Establish the basic equations in the analysis of solids with linear elastic behavior and the range of application of the linear-elastic theory.

- Know the criteria for the selection and use of different failure theories in the calculation of structures.

- Become familiar with some of the experimental techniques used in the calculation of stresses and strains in structures.

- Be able to calculate the stresses and strains in lattices, both isostatic and statically indeterminate. For these latter structures special emphasis is placed on the use of the force method.

- Be able to determine the stresses and strains in isostatic structures subjected to bending.

THEORETICAL CONTENTS



1. INTRODUCTION

2. CONCEPT OF STRESS

3. GENERAL THEORY OF STRAIN

4. THE ELASTIC SOLID

5. THE ELASTIC PROBLEM

6. THEORIES OF FAILURE

7. INTRODUCTION TO THE STRENGTH OF MATERIALS. PRISMATIC BAR STRUCTURES

8. AXIAL FORCE IN A TRUSS STRUCTURE

9. GENERAL THEORY OF BENDING. STRESS ANALYSIS

10. GENERAL THEORY OF BENDING. STRAIN ANALYSIS



LABORATORY PRACTICES

SESSION 1. THE TENSION TEST

SESSION 2. EXTENSOMETRY

The contents of the subject "Elasticity and Strength of Materials" are taught through lectures, practical classes, seminars and laboratory practice.

In the lectures the contents and theoretical concepts of each topic are presented with the aid of some specific publications available to the student and by the resolution of practical exercises.

In the practical classes problems based on structures and mechanical systems are solved in order to consolidate the concepts presented in the lectures.

Throughout the semester three seminars are held, in which larger problems as well as exams of previous editions are solved. The arrangement in small seminar groups propitiates an interactive resolution of problems between the professor and the students.

Along the course two laboratory practices are performed, the first corresponding to the tension test and the second dedicated to the experimental measurement method of extensometry. The practices are carried out in the "Laboratory of Strength of Materials and Structures" of the Department of Mechanical Engineering. Previously, and depending on each practice, students individually or divided into groups initially attend a theoretical presentation and solve analytically some exercise related to the practice. During the session, students are divided into smaller groups so as to carry out experimental measurements and validate their calculations. At the end of each practice, students must submit a report with the results and final conclusions.

On the virtual platform eGela, the following material is available to the students: the Student Guide, a collection of review exercises, some problems to be solved in the seminars and other problems from the examination sessions, together with the results and exam grades. All subject groups have at their disposal the same material simultaneously.

• Final Assessment System
• Tools and qualification percentages:
  • Written test to be taken (%): 95
  • Realization of Practical Work (exercises, cases or problems) (%): 5

In this subject a partial exam is proposed that allows reducing contents in the final exam. It will be assumed that by not doing or not obtaining the required grade in this partial exam the student is giving up the continuous assessment system.

The requirements for passing the course are:

1. Attend all laboratory practices.

2. Get an average rating greater than or equal to 5.0.

The laboratory practices account for 5% and the written tests for 95% of the final grade. The written tests consist of individual resolution of problems and theoretical questions. The first written test enables to pass definitively the first part of the course (for this it is necessary to obtain a rating equal to or greater than 4.0). In the second part of the course, a score equal to or greater than 3.5 should be obtained in order to be able to get a pass average. The final grade is the average of the two partial tests. Students may also make a full examination even after having passed the first of the written tests. The theoretical part of the exam is in any case one third of the mark for each exam.

According to the current regulations of the University of the Basque Country - EHU, it is sufficient for the student not to present himself to give up the corresponding call.

In the extraordinary examination a written exam including the full course will be performed. This will consist of individual resolution of problems and theoretical questions. The theoretical part accounts for one third of the exam. The final grade will be obtained by taking the laboratory practices into account.

As in the ordinary call, to give up this call it will be sufficient for the student not to present himself.

- "Elasticidad y Resistencia de Materiales", José Luis Alcaraz, Rubén Ansola, Javier Canales, José A. Tárrago, Estrella Veguería. Sección de Publicaciones de la E.T.S.I. de Bilbao, 2015.
- "Elasticidad y Resistencia de Materiales: Colección de Problemas de clase", José Luis Alcaraz, Rubén Ansola, Javier Canales, José A. Tárrago, Estrella Veguería. Sección de Publicaciones de la E.T.S.I. de Bilbao, 2016.

Basic bibliography

- "Elastikotasuna eta Materialen Erresistentzia", Rubén Ansola. UEU, Udako Euskal Unibertsitatea, 2005.

- "Resistencia de Materiales". L. Ortiz Berrocal. McGraw-Hill, 1991.

- "Mecánica de Materiales" (2ª ed.), S.P. Timoshenko y J.M. Gere. Grupo

Editorial Iberoamericana, 1986.

- "Mecánica de Materiales" (2ª ed.), F.P. Beer y E.R. Johnston. McGraw-Hill, 1993.

- "Resistencia de Materiales", V.I. Feodosiev. Mir, 1980.

- "Problemas de Resistencia de Materiales", I. Miroliúbov et al. Mir, 1978.

In-depth bibliography

- "Advanced Mechanics of Materials (6th Ed.)", A.P. Boresi y R.J. Schmidt. John Wiley & Sons, 2003.
- "Advanced Strength and Applied Elasticity", A.C. Ugural y S.K. Fenster. Prentice Hall, 1995.
- "Mechanics of Materials (2nd Ed.)", R.R. Craig Jr. John Wiley & Sons, 2000.

Journals

- Int. J. of Mechanical Sciences, Elsevier.
- Int. J. of Solids and Structures,Elsevier.
- Mechanics of Materials, Elsevier.
- Computers & Structures, Elsevier.

Web addresses

- https://egela.ehu.es/
- http://www.ehu.eus/es/web/ingenieria-mecanica
- es.scribd.com/doc/305851/Resistencia-de-materiales-Problemas-resueltos
- es.wikipedia.org/wiki/Resistencia_de_materiales