THEORY AND DESIGN OF STEEL STRUCTURES

Prof. Piero Gelfi

Anno Accademico 1997-98

 

Course objectives: The course is designed for engineering students who have already taken the course in Advanced Structural Mechanics. The course explains the specific problems of metal structures by using a design approach, without renouncing the rigorous formulation of the problems, in order to keep up with the rapid evolution of the norms. Particular attention will be given to the new norms of the Eurocodes. In addition to the lectures, practical applications with design examples of structural elements will be illustrated. The course concludes with the design of a steel structure complete with working drawings.

Contents and organization of the course: The course lasts one academic semester and is articulated in theoretical lectures and practical application. There will be visits to construction sites. The main topics are summarised in the following.

1. Structural Systems: Kinematics, stability, space behaviour. Comparisons with the behaviour of the reinforced concrete structures. Multi-storey and single-storey buildings. Calculation models.

2. Reliability of Steel Structures: Critical considerations concerning the allowable stress method. The semi-probabilistic method.

3. Loads: Permanent, imposed and climatic loads.

4. The Material: Structural steels. Shapes. Structural and geometrical imperfections. Quality and laboratory controls. Resistance criteria. Verification methods.

5. Welds: Technology of welds. Strength of welded joints. Calculation methods.

6. Bolts: Technology of bolts. Strength of bolted joints. Calculation methods.

7. Connections: Joint ductility. Lamellar tearing. Articulated joints. Joints in tension, in compression, in bending. Beam-column joints. Column-foundation joints. Section-composition joints.

8. Strength of structural elements: Serviceability limit state. Conventional elastic limit state. Plastic limit state.

9. Stability of structural elements: Centrally compressed members: influence of imperfections, recommended curves. Bent members. Beam columns: plate buckling, Flexural-torsional buckling. Local buckling: elements in compression, web crippling. Frame members. Stiffened plane plates.

10. Fatigue strength: Constant and variable cyclic loads. Damage accumulation laws. Verification methods according to the norms.

Suggested textbooks:

G. Ballio F. M. Mazzolani, Costruzioni in acciaio, Mondadori.

M. Caironi, Teoria e tecnica delle costruzioni - Instabilità dei telai, Clup.

M. Caironi, Teoria e tecnica delle costruzioni - Elementi di strutture in acciaio, Clup.

W. McGuire, Steel Structures, Prentice-Hall.

P. Pozzati C. Ceccoli, Teoria e tecnica delle strutture, vol. 2, UTET.

Norme tecniche per le opere in cemento armato normale e precompresso e per le strutture metalliche. Decreto Ministeriale 9/1/96.

Eurocode 3.

Final examination:

The examination is based on a comprehensive oral evaluation of the candidate over the contents of the course and on a discussion on the design carried out.