Learning objectives
1°- Knowledge and understanding
At the end of the lessons the student will know the basic principles for classification and characterization of rock masses, the different methods to be adopted for the slope stability analysis (for both rock and soil), the main reinforcement techniques for unstable slopes. He will understand the technical-scientific terminology in the field.
2°- Applying knowledge and understanding
The student will be able to carry out a slope stability analysis (either for rock or soil) through classical methods, by using a specific numerical code. The student will be also able to give suggestions for possible reinforcement works.
3°- Making judgments
The student will acquire the ability to interpret both field and laboratory geotechnical data and to model a real problem, in order to find the technically sound design solutions.
4°- Communication skills
On passing the exam, the student should have acquired sufficient proper use of the language with regard to the topic specific terminology. The student will be able to write a report dealing with the stability analysis of a typical slope.
5°- Learning skills
The student should have acquired the basic knowledge of the discipline that will allow him to choose the appropriate methods to tackle a case study
independently.
Prerequisites
A good knowledge of the fundamental of Geotechnics is strongly recommended.
Course unit content
The course aims to form the fundamental principles of rock mechanics, by giving complementary topics in respect to those given during the Geotechnics course, in order to solve problems regarding Geotechnical Engineering, with a particular reference to environmental problems, such as slope stability. The course also aims to provide the necessary tools for the design of slope stabilization works.
Full programme
Introduction:
Recalls on the basic aspects of soil mechanics. Recalls on geotechnical characterization from in situ and laboratory investigations. Definition of the geotechnical model.
Rock mechanics:
Description of rock masses and joints. Methods of site investigation of rock masses. Laboratory investigations on intact rock and joints. Geotechnical characterization of a rock mass and quality classes. Strength criteria for intact rock and rock mass. Tensions, deformations and mechanical behaviour of rock materials. The stability of soil and rock slopes. The planar sliding in rock and along intersection of joints. Tipping in rocks: the limit equilibrium methods for bending over blocks. Basic notes about rock avalanches. Numerical methods for rock slope stability analysis and application cases.
Slope stability:
General characteristics of natural and artificial slopes made by soil and rock. Stability analysis: definition of the safety factor. Infinitely extended slope. The stability of an excavation face and calculation of the safety factor of a clay slope. Theory of limit equilibrium methods. Methods of slices: general formulation. Methods of Fellenius, Bishop, Janbu, Spencer, Morgenstern & Price. Comparison between different methods of slices. Stability analysis under seismic conditions and pseudo-static method. Regulation references on slope stability analysis.
Case study: Stability analysis of a slope based on limit equilibrium methods using the SLIDE (Rocscience) calculation code.
Case study: Stability analysis of a slope based on FE methods, using the RS2 (Rocscience) calculation code.
Analysis of the regime of interstitial pressures in natural slopes. Filtration patterns on natural and artificial slopes. Application of the finite element method to filtration problems: examples of application on natural slopes and river banks.
Slope stabilization works:
Basic concepts on earth pressure (active and passive failure conditions). Slope stabilization interventions: general intervention and design criteria. Criteria for design and verification of retaining walls and sheet piles. Piles for slope stabilization. Criteria for design and verification of anchoring tie-rods. Stabilization through the use of geotextiles, reinforced soil and drainage works. Examples of real cases.
Seminar activities:
Shallow landslide movements induced by rainfall. Trigger risk assessment approaches. Numerical analysis of the safety factor as the rainfall diagram changes. Multi-scale stability analysis: from slope scale to regional scale. Real-time monitoring platforms.
Bibliography
Recommended books::
Airò Farulla C.: Analisi di stabilità dei pendii. Hevelius Edizioni
Barla M.: Elementi di meccanica e Ingegneria delle rocce. Ed. Celid
Froldi P.: Progettazione delle opere geotecniche secondo le NTC 2018 e gli Eurocodici. Maggioli Editore.
More detailed books:
Bromhead E.N.: The Stability of Slopes. Blachie and Son ltd R.
Lu N. & Godt J.: Hillslope hydrology and stability. Ed. Cambridge.
Cornforth D.H.: Landslides in practice. Ed. John Wiley and Sons
Additional teaching material:
Electronic copy of the slides used during the course.
Teaching methods
The course consists of a series of lectures and numerical exercises in a computer lab.
The lessons are carried out using presentations in Power Point. A copy of the presentations used is available on the Elly platform since the beginning of the course. The teaching material on Elly is however updated weekly by the teacher. The course slides on Elly are considered an integral part of the reference bibliography. The exercises are presented in the classroom and carried out numerically.
Should it be necessary to conduct the distance learning activities, the lessons will be held in telepresence through the use of the Teams and Elly platforms. In particular, lessons will be carried out in synchronous mode (via Teams) with direct participation of the students, and also asynchronous (slides and recorded lessons, uploaded on the Elly page of the course). During the lessons in synchronous mode (direct), there will be alternating mainly frontal and interactive moments with the students. To promote active participation in the course, various activities (exercises) will be proposed both individually and in small groups, through the use of the resources present in Elly, such as discussion forums and logbooks.
The numerical exercises will be carried out independently by each student, through the use of a personal version of the necessary software. The exercises will then be shared and discussed during the lesson in synchronous mode.
Assessment methods and criteria
The verification of the preparation consists of a practical test and an oral interview.
The practical test consists of the preparation of a report concerning the stability analysis of a typical slope and the design of possible consolidation works. The report is a summary of the laboratory exercises carried out during the course.
In the oral interview, the student must present the contents of the report and demonstrate that he or she has a thorough knowledge of the topics
covered in the course lessons.
In the oral interview the student will have to answer theoretical questions, also concerning the application of theory to original problems.
In the evaluation of the tests the different components of learning will be weighted as follows: 40% for the ability to analyze a real problem
(competence), 30% for the identification of the most convenient procedure of solution (autonomy of judgment), 30% for the ability to
exposure specialist (communicative ability).
The final grade, including the above components, is expressed globally in thirtieths and is proposed to the student at the end of the oral interview.
Other information
Attending class lessons is strongly recommended.
