The course is aimed at providing competence on structural analysis of mechanical components. The expected learning outcome, which will be verified on examinations, is the capability of evaluating the performance of the most common mechanical components in terms of mechanical resistance under the proper working condition. The course contents complete the stock of knowledge useful for designing machines, implants and control systems.
Statics of structures, continuum mechanics, properties of aeras, theory of De Saint Venant, static resistance, fatigue, concepts of mechanical design.
STATICS OF STRUCTURES: Real structures and calculation models. Loads and constraints. Calculation of reaction forces. Diagrams of internal loads in isostatic structures: tensile force, shearing, bending and torque.
CONTINUUM MECHANICS: Fundamental equations, stress and strain tensor, proncipal stresses, Mohr circles.
PROPERTIES OF AREAS: Area, first moments, center of area, second moments. Application to common beam sections.
THEORY OF DE SAINT VENANT: stress tensor in beams in the cases of tension force, bending, shearing and torsion.
STATIC RESISTANCE: Static mechanical properties of materials. Static criteria: Rankine-Navier, Guest-Tresca, Ros-Eichinger, von Mises. Notch effect.
FATIGUE: Phenomenon description, Wohler curve, notch, surface and dimension effect. Haigh and Smith diagrams. Multi-axial fatigue: criterion of Gough-Pollard. Finite life fatigue: the Miner's rule.
CONCEPTS OF MECHANICAL DESIGN: Shafts of gear and belt transmissions, shafts of cranks for simple and double effect pumps.
Solazzi L., Fondamenti di progettazione di macchine resistenza dei materiali, 2^ ed., Cartoleria Snoopy, Brescia, 2010
Donzella G., Mazzù A., Petrogalli C., Costruzione di Macchine, Parte 2: Fatica, Cartolibreria Snoopy edizioni, 2013
A. Bernasconi, M. Filippini, M. Giglio, A. Lo Conte, G. Petrone, M. Sangirardi, Fondamenti di costruzione di macchine, McGraw-Hill, 2006 (second edition)
Davoli, Vergani, Beretta, Guagliano, Baragetti, Costruzione di Macchine 1, McGraw-Hill, 2007 (second edition)
Frontal lectures and exercises.
The examination is aimed at verifying the knowledge of the course topics and the capability of exercise solving. The examination includes a written part and an oral part, according to the following procedure. WRITTEN: a grade less than 15/30 is considered insufficient. During the written test, notes and books, as well as a calculator, are allowed; cellphones or smartphones are not allowed. The written test, consisting in an exercise divided in 2-5 points, will not be more difficult than the exercises solved during the frontal exercises. ORAL: a grade equal or higher than 15/30 in the written test is necessary to be admitted to the oral examination. The oral examination will be focused on the theory covered in the course and can be taken even on an examination session later than the one of the written test. If the grade of the written test is from 15/30 to 17/30, the oral examination will be focused on the solution of exercises as well. An intermediate test will be held during the course: its result will be taken into account for the final examination grading, if required by the student, provided that the final examination will be held within the academic year of the course.