B024532 - PRINCIPLES OF MECHANICAL DESIGN

Italian

The course aims to provide students with the most effective methods for the design and verification of the strength of simple structural systems, with particular reference to the typical problems of mechanical design.

- E.Viola. Esercitazioni di scienza delle costruzioni. Pitagora
- F.P. Beer, E. Russell Johnston Jr., J.T. DeWolf, D.F. Mazurek, Mechanics of Materials. McGraw Hill Educational
- V.Franciosi. Scienza delle costruzioni. Liguori

The main goal of the course is to provide students with the knowledge required to properly identify and solve the structural problems related to the design of structures subjected to static loads. Together with the connected course of Strength of Materials the course has the following objectives:
- To provide knowledge and understanding of the key aspects of mechanical design of industrial engineering concerning the structural field. In particular, understanding of which are the most suitable methods of analysis and calculation in order to define a product and its characteristics. The modelling of parts and assemblies, their dimensioning, their static behaviour and interactions between components are areas of knowledge and understanding (cc3).
- To apply knowledge and understanding related to the most appropriate methods of analysis, modelling, verification and experimentation to design, analyse and test machines. This includes: the sizing and the functional and structural verification of components and mechanical groups subjected to static stress; the functional setting of the design of a mechanical system, applying the principles of kinematics and static principles; analysis of the characteristics of metallic materials for the production (ca3).

Concept of force and moment of a force. Vectors and vector operations. Constraints and degrees of freedom of a system. Static and dynamic equilibrium.
Differentiation and integration of the elementary functions. Matrix calculation. Fundamental aspects of structure and properties of the materials.

Lectures and exercises in the classroom

The examination consists of a written test, concerning:
- The solution of some problems, which demonstrates the ability to think critically.
- Some questions regarding the theoretical topics dealt with in the course are also included: the student must provide a concise and exhaustive description.
The student must show a satisfactory knowledge of the theoretical concepts presented in the course. Moreover, the student must know how to apply this knowledge to simple applied task. To pass the test, the students must demonstrate they have achieved the "cc3" and "ca3" objectives.

Geometry of areas. Centroid, static moments, moments of inertia. Laws of transformation. Principal axes. Mohr’s circle. Ellipse of inertia.
-Beams and frames structural systems: evaluation of constraint reactions, diagrams of characteristics of internal forces for both two and three dimensional solids.
-Notched components. Geometric stress concentration factor.
-Analysis of stresses in simple mechanical components.
-Equivalent stress and safety coefficient
-Mechanical behaviour of materials: tensile test and overview of fatigue behaviour.
-Failure criteria for static load: stress criteria by Rankine, Tresca, Von Mises and Mohr.
-Design and verification of elements subjected to assigned loads and geometry.
-Elastic stability of structure: definition critical load; structures with concentrated deformability, the ideal pin-ended column. Slenderness ratio of a beam. Euler buckling load. Secant formula.