Applied Mechanics

n.a.

The teaching method of the course will be mostly student-centered, using structural components of daily use, which the student, alone or in a group, will have to analyze and understand, within the scope of mechanics concepts.

The bases for the introduction of the nuclear concepts involve the use of several types of methodologies of exposition and discussion. Thus, the following will be implemented:

– Exhibition of content using electronic presentations, to be made available to students as complementary documentation to support the UC;

– Visualization of multimedia content;
– Visualization of components and structural assemblies to support the UC.

Students will be presented with several challenges that contribute to the assessment process, contextualized in the various domains of the course. These challenges involve solving problems associated with understanding the functioning of some structural elements applicable in everyday life, as well as the design, development and construction of structural elements for defined objectives.

Also, exercises to apply each of the UC concepts will be solved, which will serve as a basis for the apprehension of knowledge and the development of challenges.

The Applied Mechanics studies the behavior of structural elements. So the principal goal of this curricular unit is that the students acquire knowledge enabling to understand the behavior of these elements used in an industrial environment, with particular emphasis on the areas of mechanical. Skills: The student should be able to understand which conditions of use and the stresses to which the structural elements are subject, as well as determining the material more convenient shape and dimensions better suited to withstand various types of external stresses applied to machines, parts, parts of structures, etc … at the lowest possible cost and adequate security.

1. Introduction

What is Mechanics? Fundamental concepts. Newton’s laws. International System of Units (SI).

2 – Static

2.1 – Mechanical action on a mechanical structure: forces (concentrated forces and distributed forces) and moment (moment of a force and torque ). Types of support of a structure.

2.2 – Degrees of freedom of a body. Static balance of a body. Free body diagram. Determination of reactions in the supports of an isostatic structure. Internal forces developed in a mechanical structure: axial forces, transverse forces, bending moments and torsion moments. Diagrams.

2.3 – Geometric properties of areas. Geometric center of a area. Moment of inertia. Steiner’s theorem. Polar moment of inertia. Cross section properties of some structural steel profiles.

3 – Basic Concepts of Strength of Materials

Stress concept: normal stress and shear stress. Concept of displacement and deformation. Resistance electric strain gauge. Hooke’s law. Stress diagrams – deformation for ductile and fragile materials. Concept of elasticity and plasticity. Mechanical properties of materials. Principle of Overlapping Effects of Forces. Potential Deformation Energy. Concept of Resilience and Tenacity of a material. Basic design of a mechanical structure. Notion of safety factor.

4 – Structural Elements subject to Axial Stresses

Stresses in bars axially loaded. Saint-Venant principle. Elongation of a bar with axial solicitation. Influence of temperature on the stretching of a bar. Statically undetermined structures.

5 – Structural elements subject to torsion

Pure shear. Twist on circular and non-circular sections. Study of thin-walled closed profiles. Twist in statically undetermined structures. Power transmitted by a motor to a shaft.

6 – Structural Elements subject to Flexion

Bending of straight axis beams: pure bending, simple bending. Normal compressive and tensile stresses. Neutral line equation. Bending shear stresses. Static moment for a circular, rectangular, T-shaped and I-shaped cross section. Calculation of displacements and rotations in beams using practical tables provided in the moodle. 7 – Experimental Stress Analysis Basic concepts and principle of operation. Types of odometers. Specifications and selection of strain gauges. Gluing and assembly techniques for strain gauges. Load cells. Application examples.

NAO

Antunes, F. (2012). Mecânica Aplicada – Uma Abordagem Prática. Lidel.

Beer, F.; Johnston, P.; Russell, E.;  DeWolf, J. (2006). Resistência dos Materiais (4^a edição). McGraw Hill.

Farinha, J. S. B.; Correia dos Reis, A. (1992). Tabelas Técnicas (Edição P.O.B.).

Gomes, P.  (2015). Resistência dos Materiais. [S.I.] J.

Hibbeler, R. C. (2005). Estática – Mecânica para Engenharia (10^a edição). Pearson Prentice Hall.

Hibbeler, R. C. (2006). Resistência dos Materiais (5^a edição). Pearson Prentice Hall.