99641 - Principles of Structural Engineering

Learning outcomes

Through this course the student learns the basic elements of Structural Engineering. At the end of the class, the student has acquired the skills in design of the structural systems aimed at the stability of buildings: evaluation of the structural safety through probabilistic approaches, construction materials, direct and indirect actions, structural modelling and analysis, verification of structural elements realized with reinforced concrete and structural steel, design and construction criteria, construction details, codes for structural design.

Course contents

Pre-requirements

Students enrolled in the course must know the concept of vectors, forces, mass geometry, and they should be able to manage the principal methods for the resolution of isostatic and basing methods for solving simple statically redundant structures (such as force method, virtual work principle, etc). They also must have a sound knowledge of the beam’s theory and of cross-section analysis for linear homogeneous materials. Students must also be familiar with the concepts equilibrium and compatibility and the main aspects of statics.

The aforementioned topics are typically covered in the course of Principles of Structural Mechanics.

All the lectures will be held in English Language.

 

Program

The course is subdivided into two teaching units:

1) the first module focuses on the subject of structural design, presents the technical codes, the building materials, the actions on the structures, methods of solving isostatic and hyperstatic structures, the methods of verification of the structural elements;

2) the second module refers to the design of conventional structures in reinforced concrete and steel, in accordance with the Eurocodes.

 

Module 1 (Prof. Luca Landi)

Introduction to structural design

- The design process. Reference standards. Limit state design approach. Elements of probability theory. General rules of the limit states design. Allowable stress approach.

- Materials. Reinforced concrete: technology; mechanical characterization, conformity, tests. Steel: strength classes, requirements, conformity.

- Actions on structures. Dead loads. Live loads and variable actions on structures (snow, wind, etc.). Seismic action. Load combinations.

- Brief notes on the conceptual approach to structural design, the path of loads towards the ground, the systems of vertical-resisting elements, the systems of lateral-resisting elements. Frequent structural typologies.

 

Resolution of structures

- Restraints and definitions of isostatic and hyperstatic structures.

- Calculation of isostatic structures. Applications of the Principle of Virtual Works for the evaluation of displacements/rotations.

- Calculation of hyperstatic structures with the congruence method. Fundamental cases of single-span beams. Rotational stiffnesses.

- Calculation of hyperstatic structures with the equilibrium method and with the auxiliary restraints method. Multi-span beam and simple frame applications. Symmetrical structures with symmetrical and antimetric loading. Structures with nodes that rotate and do not translate: rotational stiffnesses; Cross's method. Structures with nodes that translate and do not rotate: translational stiffnesses. Structures with nodes that both translate and rotate.

 

Verification of structural elements

- Design of reinforced concrete frames. Identification of the structural layout of a building. Three-dimensional organization of the structural elements.

- Verification of reinforced concrete elements: working stress method. Homogenization coefficient. Analysis of RC sections in bending. Preliminary criteria for structural elements.

- Verification of reinforced concrete elements: limit state design method. Constitutive laws for materials. Failure modes for cross sections in bending. Ultimate moment for bending actions. Elements subjected to axial and bending actions: interaction between M-N. Simplified rules for design and verification. Verification and design of elements against shear actions.

- Verification of structural steel elements: deformability checks, strength verifications and buckling. Allowable stress methods and limit state method.

 

Module 2 (Ing. Stefano Gagliardi)

Applicative examples of design of reinforced concrete and steel structures

- Review of geometry of masses. The concept of moment of inertia.

- Design of floors. Load analysis. Recurring types of floors: brick-concrete, steel and wooden floors.

- Structural typologies in reinforced concrete.

- Design of reinforced concrete girders. Beams in height and in thickness. General criteria for the evaluation of internal actions and for the general sizing of the beams. Loading conditions for maximum stress values. Formwork drawings and arrangement of bending and shear reinforcement. Detailing rules.

- Design of reinforced concrete columns. Preliminary design of columns. Loading conditions. Design criteria and reinforcement layout. Detailing rules.

- Structural typologies in steel material.

- General design rules. Strength verification of elements (classes 1-3) against tension, compression, shear and bending actions.

- Deformation limits.

- Stability of compressed elements, Euler’s theory and real behavior of compressed elements.

- Bolted connections. Welded connections. Connection systems with the foundations.

- Design of foundations. Loads on the foundations. Continuous (beams) and isolated foundations (squat or slender footings). Simplified analysis of continuous foundations. General design rules. Detailing and reinforcement layout.

Readings/Bibliography

Suggested books:

Lecture notes.

- J. Heyman, 1998, “Structural analysis. A historical approach”, Cambridge University Press

- E. Viola, “Fondamenti di Analisi Matriciale delle Strutture”, Pitagora Editrice Bologna, 1996.

- O. Belluzzi, “Scienza delle costruzioni”, ed. Zanichelli, Bologna, voll. II e III.

- P. Pozzati e C. Ceccoli, “Teoria e Tecnica delle strutture”, ed. UTET, Torino, volumi I e II, 1972 – 1974.

- A. Migliacci, “Progetti di strutture”, Tamburini, Milano, 1968.

- E. Giangreco, “Ingegneria delle strutture”, UTET

- E. Torroja, “La concezione strutturale”, UTET

- Bill Mosley, John Bungey and Ray Hulse, “Reinforced Concrete Design to Eurocode 2”, Sixth Edition, Palgrave Macmillan.

- R. Park, T. Paulay, Reinforced Concrete Structures, 1975, John Wiley & Sons, Inc.

- T.Y. Lin, N.H. Burns, 1982, "Design of prestressed concrete structures", Wiley

- E. Cosenza, C. Greco, “Il calcolo delle deformazioni nelle strutture in cemento armato”. CUEN, Napoli, 1996.

- E. Cosenza, G. Manfredi, M. Pecce, “Strutture in cemento armato”, Hoepli, 2008.

- A. Ghersi, “Costruzioni in Cemento Armato”, Flaccovio editore, 2010.

- F. Leonhardt, “C.A. & C.A.P.: calcolo di progetto & tecniche costruttive”. Edizioni Tecniche, Milano, voll. I-III, 1977.

- A. Migliacci, “Progetto agli stati limite delle strutture in c.a.”, Masson Italia Ed., Milano, 1977.

- L. Santarella, 1998, "Il cemento armato", 22a ediz., Hoepli

- R. Walther, M.Miehlbradt, 1990, "Progettare in calcestruzzo armato", Hoepli

- C. Cestelli-Guidi, 1987, "Cemento armato precompresso", Hoepli

- L. Goffi, P. Marro, 1998, "Appunti sul Cemento armato precompresso", CLUT editrice, Torino

- J.C. McCormac, 2008, "Structural steel design", Pearson Prentice Hall

- J.C. Smith, 1996, "Structural steel design. LRFD approach", Wiley

- S.P. Timoshenko, J.M. Gere, 1961, "Theory of elastic stability", Dover publications

- T.V. Galambos, A.E. Surovek, 2008, "Structural stability of steel", Wiley

- G. Ballio, F.M. Mazzolani, “Strutture in acciaio”, Hoepli, 1987.

- G. Ballio, C. Bernuzzi, 2004, “Progettare costruzioni in acciaio”, Hoepli.

- V. Nunziata, “Teoria e pratica delle strutture in acciaio”, Flaccovio editore, 2011.

- N. Scibilia, 2005, “Progetto di strutture in acciaio”, 4° ed., Dario Flaccovio Editore.

- F. Hart, W. Henn, H. Sontag, 1982, “Architettura Acciaio Edifici Civili”, 2° ed., FINSIDER Gruppo IRI (edizione FINSIDER in lingua italiana del volume “Stahlbauatlas-Geschossbauten”, 2° ed., pubblicato dall'Institut für Internationale Architektur-Dokumentation di Monaco).

From the technical-scientific book series for the design of steel structures by ITALSIDER:

- L.F. Donato, L. Sanpaolesi, 1970, “Gli acciai e la sicurezza delle costruzioni”, Volume I.

- L. Finzi, E. Nova, 1971, “Elementi strutturali”, Volume IV.

- D. Danieli, F. De Miranda, 1971, “Strutture in acciaio per l'edilizia civile e industriale”, Volume VI.

 

Reference standards:

Eurocode 1: Actions on structures

Eurocode 2: Design of concrete structures

Eurocode 3: Design of steel structures

Norme Tecniche per le Costruzioni – D.M. 17/01/2018.

Circolare 21/01/2019, n. 617, C.S.LL.PP.

CNR 10011, Costruzioni in acciaio, 1988.

Teaching methods

Frontal lessons mainly at the blackboard (occasional use of Power-Point slides).
Numerical applicative examples at the blackboard. Homework assignments.

Assessment methods

Achievements will be assessed by an overall (for all two modules) final exam aimed at evaluating the achievement of the requested knowledge with questions abut the contents of the program reported above. Specifically: basis of structural design, resolution of hyperstatic structures, design and verification criteria of structural elements.

The oral test is aimed at checking if the student has understood the subject in its theoretical aspects and if they are able to apply what studied in specific practical contexts.

To obtain a passing grade, students are required to at least demonstrate a sufficient knowledge of the key concepts of the subject. Higher grades will be awarded to students who demostrate a full and organic understanding of the subject, a high ability for critical application, an independent operative capacity to solve complex exercises and problems. A falling grade will be awarded if the student shows knowledge gaps in key concepts of the subject and/or inappropriate use of technical language.

Teaching tools

Possible lecture-notes supplied by the teacher.
Power-Point presentations. Design examples.

Office hours

See the website of Luca Landi

See the website of Stefano Gagliardi