


Politecnico di Torino  
Academic Year 2012/13  
09IHRMN, 09IHRLN Fundamentals of structural mechanics 

1st degree and Bachelorlevel of the Bologna process in Mechanical Engineering  Torino 1st degree and Bachelorlevel of the Bologna process in Automotive Engineering  Torino 





Subject fundamentals
The course aims to provide the fundamental basis to perform the design and verification of structural components and mechanical systems subject to static and fatigue loads.
Topics covered, after a resume of static equilibrium concepts, are:  evaluation of the elastic properties and the static strength of materials by tensile test and some notes on creep;  state of stress and state of strain in mechanical elements in linear elastic conditions; combined stress failure theories; static safety factors;  calculation of stresses in onedimensional structural elements subjected to loads in plane and space: geometric properties of areas, de St Venant solid, equilibrium and internal forces diagrams in statically determinate systems; extensional, flexural, torsional and shear behaviour; equation of the elastic curve; elastic instability;  definition and effect of notches: the stress concentration factor; static component verification;  high cycle fatigue strength in terms of uniaxial stress: cyclic stress, nucleation and propagation of cracks, diagrams for the presentation of fatigue tests results; application to the verification of mechanical components, the main factors reducing the fatigue strength. 
Expected learning outcomes
Knowledge and understanding of the mechanical properties and strength of materials
Knowledge of methods for describing the state of stress and the state of strain in linear elastic conditions Knowledge of static failure criteria and the concept of safety factor Knowledge of methods for assessing the state of strain, stress and displacements in onedimensional structural elements Understanding the phenomenon of fatigue; knowledge of diagrams that describe the high cycle fatigue behaviour of materials. Knowledge of methods of verification of components subject to constant amplitude cycling stresses. Ability to verify elements subject to known static stress. Ability to calculate reaction forces of statically determinate structures. Ability to calculate the internal forces diagrams in statically determinate elements subject to known applied loads. Ability to assess the stresses and strain in sections of onedimensional elements with and without notches , known the internal forces applied to the section. Ability to perform fatigue assessment of components subject to constant amplitude cycling stresses. 
Prerequisites / Assumed knowledge
Concepts of mathematics (study of functions and computation of derivatives and integrals, matrix algebra, eigenvalue / eigenvectors problems) and physics (basic concepts of kinematics and statics).

Contents
The course content will be distributed as follows:
  stress and strain state (3 hours);   stress and strain state in monodimensional structural elements subjected to plane and spatial loading conditions (de St Venant theory): tension/compression, bending, shear, torsion (20 hours);   mechanical properties of materials, failure criteria and safety coefficients (6 hours);   deformed shape of bending beams and overconstrained problem solution (5 hours);   linear buckling (2 hours);   introduction to the finite element method: matricial calculus (6 hours). 
Delivery modes
The course is subdivided in:
  theory lessons (43/45 hours),   practical classes on the subjects presented at the theory classes (36/38 hours). 
Texts, readings, handouts and other learning resources
Suggested textbooks:
 Somà A. Fondamenti di meccanica strutturale  Curti G., Cura F. Fondamenti di meccanica strutturale  Raffa F. Elementi di meccanica strutturale Suggested notes:  Goglio L. Fondamenti di meccanica strutturale 
Assessment and grading criteria
The exam of the course Fondamenti di Meccanica Strutturale is characterized by a written part and an oral part. The written and the oral exams must be taken during the same call.
The written exam, whose lasting is equal to 2 hours, consists in the solution of 23 exercises concerning the subjects faced during the course and the score is a number running from 0 to 30. Course notes and every other didactical stuff (handbooks, manuals) can be used during the written exam. The written exam can be passed if and only if a few explicitly specified questions related to the proposed exercises have been answered correctly (18/30): if the wrong answer is provided, the answers to the remaining questions posed for each proposed exercise will not further taken into account in the correction process. The written exam has to be clear enough from the text and graphical rational point of view in order to be taken into account in the correction process. A positive evaluation of the written/oral exam can be rejected. Score rejection must be explicitly communicated during the examination process. The oral exam can be attended only by students having reached a minimum score of 18/30 in the written exam and the score is a number running from 0 to 30. The oral exam consists in a minimum of 2 questions on the contents of the complete course (answers must be provided in a reasonable but limited time span). If the oral exam is not attended, the final score of the exam will correspond to the score of the written exam if it is comprised between 18/30 and 21/30, and will correspond to 22/30 if the score of the written exam is larger than 21/30. The absence (no presence) of the student at the oral exam is considered as the implicit acceptance of the score of the written exam if it ranges between 18/30 and 21/30 or the implicit acceptance of the score of 22/30 if the score of the written exam is larger than 21/30. The overall score is defined as an average of the two scores reached in the written and in the oral parts. 
