Soil Dynamics
Course Description:
Introduction: problems and significance of soil dynamics. Dynamics of simple (mass-spring-dashpot) systems under base excitation. Concept and applications of response spectrum for the seismic design of structures. One-dimensional wave propagation, reflection and refraction, propagating and stationary waves. Two-dimensional wave propagation, Rayleigh and Love waves. Soil behaviour under dynamic and cyclic loading, for small, medium and large cyclic strains. Measurements of seismic soil parameters in the laboratory and in situ. Constitutive models for the simulation of the visco-elastic cyclic soil response. Analytical and numerical seismic response analysis of soil sites (“soil amplification” of seismic motion). Liquefaction of saturated granular soils: evaluation of liquefaction potential, assessment of liquefaction effects on engineering structures, methods for liquefaction mitigation
- Semester 9
- Teaching hours 4
- Instructors George Bouckovalas (Coordinator)
Prerequisite Knowledge
Soil Mechanics, Structural DynamicsCourse Units
| # | Title | Description | Hours |
|---|---|---|---|
| 1 | Introduction | Problems and significance of Soil Dynamics. Course organization. | 0.5Χ4=2 |
| 2 | Dynamics of 1DOF systems under base excitation | Dynamic response of 1DOF systems under harmonic base excitation, Elastic Response spectra. | 1.5Χ4=6 |
| 3 | 1D wave propagation in soils | P & S wave propagation equation, refraction & reflection phenomena. | 2Χ4=8 |
| 4 | 3D wave propagation in soils | Refraction and reflection of P & S waves at interfaces, Snell’s Law, Rayleigh and Love waves. | 1x4=4 |
| 5 | Cyclic soil response | Shear modulus & hysteretic damping degradation, permanent strain accumulation & excess pore pressure build up due to cyclic loading. | 2Χ4=8 |
| 6 | Measurement of seismic soil parameters | Laboratory & in situ measurement of seismic soil properties for small-medium-large cyclic strains. Student training in the execution and interpretation of Crosshole and Downhole tests. | 2Χ4=8 |
| 7 | Seismic ground response ("soil amplification”) | Analytical and numerical analysis of seismic ground response with the frequency domain (equivalent linear) and the time domain (non-linear) methods. Term project for a typical site and bridge foundation. | 2Χ4=4 |
| 8 | Earthquake-induced soil liquefaction | Methods of liquefaction potential evaluation. Liquefaction induced soil settlements, shear strength degradation, lateral ground spreading. Ground improvement methods to mitigate liquefaction effects. | 2Χ4=4 |
Learning Objectives
Upon completion the students will be:
Familiarized with the peculiarities and the requirements of Soil Dynamics and Geotechnical Earthquake Engineering projects, as well as with the experimental methodologies required to obtain the necessary dynamic soil properties.
Trained in state-of-the art analytical and numerical methods for assessing: (a) soil effects on seismic ground motions and design response spectra, and (b) liquefaction effects on engineering structures and design of required special construction measures.
Teaching Methods
| Teaching methods | Lectures, tutorial exercises, home-works and field exercises. |
|---|---|
| Teaching media | Power Point Presentations. Electronic submission of tutorial exercises. Filed testing demonstration. |
| Laboratories | The students perform, in groups of 2-3 persons, in situ Crosshole and Downhole measurements of seismic (S & P) wave velocities. |
| Computer and software use | The students use computer software to compute the seismic ground response of a typical construction site (term project). |
| Problems - Applications | An individual report is handed in by the students for: (a) for the in situ Crosshole and Downhole measurements, and (b) the term project. |
| Student presentations | Each group presents the results of the term project. Discussion follows each presentation. |
Student Assessment
- Final written exam: 50%
- Mid-term exam: 25%
- Problems - Applications: 25%
Textbooks - Bibliography
(α) “Σημειώσεις Εδαφοδυναμικής” Εκδοση ΕΜΠ, 2008.
(β) το βιβλίο: ΕΔΑΦΟΔΥΝΑΜΙΚΗ και ΣΕΙΣΜΙΚΗ ΜΗΧΑΝΙΚΗ : ΙΣΤΟΡΙΚΑ ΠΕΡΙΣΤΑΤΙΚΑ [Γκαζέτας, Εκδόσεις Συμεών, 1996]
(γ) το βιβλίο : ΓΕΩΤΕΧΝΙΚΗ ΣΕΙΣΜΙΚΗ ΜΗΧΑΝΙΚΗ [Πιτιλάκης, Εκδόσεις Ζήση, 2010] καθώς και ασκήσεις που αναρτώνται στο mycourses
Lecture Time - Place:
- Tuesday, 12:45 – 16:30,
Rooms:- Ζ. Κτ. 1 Πολ., Αιθ. 2