101223 - INTRODUCTION TO STRENGTH OF MATERIALS

Subject type: Mandatory

Coordinator: Julián Horrillo Tello

Trimester: Second term

Credits: 4

The subject of Introduction to the Strength of Materials provides the basic concepts, vocabulary and tools to understand how materials act when subjected to different types of efforts and moments. The concepts of static equilibrium are studied to determine the conditions of stability, normal, shear stresses, bending moments, torsions and deformations that act on a structural element. Solids are analyzed using simplified models that will later be used in the subjects of Elasticity and Strength of Materials, Materials Engineering, Machines and Mechanisms.

In general the student must be able to:

• Apply the fundamentals of elasticity and strength of materials to the behavior of real solids.
• Apply materials engineering

At the end of the course the student must be able to:

• Know the possible causes of failures of a material depending on the conditions of service.
• Perform the selection of materials in the design of components and products taking into account the specifications and processing by applying the appropriate methodology.
• Identify and evaluate the stresses and stress states in which mechanical structures and systems are applied.
• To know the mechanisms of transmission of loads and efforts to the structures.
• Know and analyze the concepts of stress and strain.
• Perform stress and strain measurements.

Classes are divided into theoretical and practical sessions.

The theoretical sessions alternate theoretical concepts with the realization of practical exercises. In a generic way, practical group exercises and individual exercises are done, so that students assimilate the main theoretical concepts.

The practical laboratory sessions delve into theoretical concepts. These practices are evaluable.

Students have all the information necessary to follow the teacher's explanations and the subject on the school's intranet, where they have theoretical notes of the concepts explained in class, as well as solved exercises so that the student can practice in a individual.

In a generic way, the contents of the subject can be grouped into the following topics:

1. Axial Load: Traction / Compression
2. Internal stresses in beams:

• Flexion
• Cutting
• Torsion

      3. Tensions and deformations in beams.

Specifically, the course will consist of the following topics:

Topic 1. Introduction and general concepts.

1.1. - Strength of materials. General concepts.

1.2. - Types of internal efforts. Classification.

1.3. - Stress diagram - deformation of a material.

1.3.1. - Obtaining the stress-strain diagram.

1.3.2. - Introduction to the concepts of stress and strain.

1.3.3. - Elastic behavior and plastic behavior of a material.

1.3.4. - Interpretation of the stress-strain diagram of steel. Young's module. Hooke's law. Ductility. Fragility. Laminating.

1.3.5. - Interpretation of the stress diagram - deformation of other materials. Aluminum. Ceramics. Concrete. Wood.

1.4. - Premises of the resistance of materials.

1.5. - Deformation stress diagram exercises.

Subject 2. Geometry of masses.

2.1. - Center of gravity.

2.2. - Area.

2.3. - Static moment.

2.4. - Moment of inertia.

2.5. - Steiner's theorem.

2.6. - Resistant module.

2.7. - Moment of polar inertia.

2.8. - Turning radius.

2.9. - Product of inertia

2.10. - Exercises.

Topic 3. Axillary effort.

3.1. - Definition of axillary effort.

3.2. - Voltage calculation.

3.3. - Calculation of deformations. Unit deformation. Hooke's law.

3.4. - Thermal stresses.

3.5. - Transverse elastic modulus or Coulomb modulus. The Fish effect.

3.6. - Characteristic parameters of the behavior of the materials.

3.7. - Isostatic, hyperstatic structures and mechanisms.

3.8. - Exercises.

Item 4. Pure inflection.

4.1. - Definition of flexion. Neutral fiber.

4.2. - Pure flexion.

4.3. - Voltage calculation. Navier's hypothesis. Resistant module.

Item 5. Simple bending.

5.1. - Definition of simple flexion.

5.2. - Normal efforts Vs normal tensions. Tangential efforts Vs.tangential stresses.

5.3. - Cutting effort. Flexion ratio Vs cutting.

5.4. - Shaving effort. Voltage calculation. Jouravski - Colignon expression. Cauchy's law.

5.5. - Particular cases of cutting effort. Rectangular, circular section, laminated profile. medium to shear stress.

5.6. - Types in flexion depending on the light. Casuistics.

5.7. - Types of cutting.

5.8. - Typologies at ground level

5.9. - Simple and pure flexion exercises.

Item 6. Composite inflection.

6.1. - Definition of compound flexion.

6.2. - Composite bending case. Eccentric armpit, oblique load, armpit and wind, retaining walls, post-tensioning / prestressing of a concrete element.

6.3. - Voltage calculation.

6.3. - Neutral line equation.

6.6. - Compound flexion exercises.

Item 7. Biased bending.

7.1. - Definition of skewed bending.

7.2. - Biased bending case. Eccentric load, deck straps, brackets.

7.3. - Voltage calculation.

7.4. - Neutral line equation.

7.5. - The central core. properties. Obtaining the central core. Generic cases: rectangular, circular, annular, laminated profile.

7.6. - Flexion type summary table. Common elements of the building.

7.7. - Biased bending exercises.

Item 8. Torsion.

8.1. - Definition of torsional stress.

8.2. - Torsional stress case.

8.3. - Torsor moment diagrams.

8.4. - Tension calculation for the case of circular sections.

8.5. - Deformational calculation for the case of circular sections. Torsional rotation.

8.6. - Uniform torsion and non-uniform torsion.

8.7. - Sections Vs torsion. Torsional stiffness of a section.

8.8. -Design of parts subjected to torsion.

8.9. - Torsional effort exercises.

- The presentation of theoretical concepts and the resolution of practical exercises will alternate in the classroom. In the lab students will work in groups of two or three students.
- Students will have the necessary documentation to follow the course.
- Students must dedicate the non-contact time to the study, the resolution of exercises, works and reports of practices, as well as to the preparation of the written tests.

• The training activities of knowledge acquisition and individual study of the student will be evaluated by means of written tests. (70%).
• The training activities related to the laboratory practices will be evaluated according to the following parameters: attendance at the practice sessions, personal attitude, individual work carried out in the laboratory, individual or group reports on the activities carried out. (30%)
• control by course through a written test with a value between +10% and -10%.

The teacher reserves the right to evaluate or not evaluate the laboratory practices and/or the final work depending on the evolution and the acquisition of knowledge by the students during the course. In case of not evaluating the practices, the written tests (control + exam) will have a value of 100% on the final grade. 

The evaluation will be continuous and will contemplate the proposals and mechanisms of recovery of the knowledge and competitions. All this within the period that comprises the matter.

To pass the course the final grade must be higher than 5 and have completed all the practices.

Failure to complete an internship without just cause will cause direct suspension of the subject.

Materials Mechanics. Gere & Timoshenko. Editions Auditorium

Materials Strength Notes.

Materials Mechanics. Hibbeler. Pearson Publishing.