MODERNE TECNICHE DI PROGETTAZIONE ANTISISMICA

Aim of the course is to provide the fundamentals of the dynamics of structures that are useful for understanding the modern seismic protection strategies of structures and nonstructural components. The learning process starts from a phenomenological approach to various problems of the dynamics of structures, to acquire the more rigorous analytical/mathematical formulations just in a second stage. The concepts illustrated during the course will be, whenever possible, explained through practical applications and experiments via the shake table testing equipment of the laboratory of structures.

At the end of the course the students will be able to assess the earthquake-induced forces on the structures, to understand the seismic design criteria and to perform seismic response analysis of structures equipped with aseismc design devices, like seismic base isolators and/or supplemental energy dissipation devices.

1. Introduction on dynamics of structures

1. The concept of single degree of freedom (SDOF)
2. Undamped free vibrations
3. Damped free vibrations
4. Forced vibration under harmonic excitations: the magnification coefficient
5. Equations of motion in terms of state space variables
6. Response to unit pulse and unit step functions
7. The concept of the response spectrum
8. Equations of motion for multi degree of freedom (MDOF) structures
9. Undamped free vibration of MDOF structures and natural modes of vibration
10. Damper free vibration of MDOF structures
11. Modal analysis of classically damped structures
12. Basics of modal analysis of nonclassically damped structures (complex modal analysis)

2. Seismic analysis of structures

1. Seismic analysis of classically damped structures
2. The modal participation factor and the modal participating mass
3. Seismic analysis of structures via the response spectrum method
4. Inelastic response of structure: the concept of ductility
5. The design response spectrum and the elastic response spectrum: guidelines from the italian seismic code
6. Basics of modelling of seismic excitation: guidelines from the italian seismic code

3. Seismic protection of structures

1. Basics of seismic base isolation
2. Constitutive models of base isolators on the basis of experimental testing
3. Design of base-isolated buildings
4. Basics of supplemental energy dissipation devices: fluid viscous dampers and hysteretic dampers
5. Constitutive models of supplemental energy dissipation devices on the basis of experimental testing
6. Design of building with supplemental energy dissipation devices

4. Applications and design projects

1. Numerical application through finite element software
2. Implementation of constitutive models of linear and nonlinear base isolators and dampers in finite element software
3. Structural models with aseismic devices
4. Comparison of conventional structure with structure equipped with isolation/dissipation devices
5. Design project

• Powerpoint presentations on all the topics of the course
• Anil K. Chopra, Dynamics of Structures 4^th edition, Pearson Prentice Hall. USA; 2012
• Ray W. Clough, Joseph Penzien, Dynamics of Structures, Computers & Structures Inc., USA, 1995
• Mauro Dolce, F.C. Ponzo, A. Di Cesare, G. Arleo. Progetto di Edifici con Isolamento Sismico, IUSS Press, 2004
• Constantin Christopoulos, André Filiatrault. Principles of Passive Supplemental Damping and Seismic Isolation, IUSS Press, 2006
• Giuseppe Muscolino, Dinamica delle Strutture, McGraw-Hill, Milano, 2002