27371 - Agricultural soil mechanics

Learning outcomes

At the end of the course, students will know all the principles of geotechnical engineering and they will be able to apply such knowledge for the design and protection of land resources.

Course contents

Lectures (36 hours):

• Basic phisics:
  Definitions of force, moment, static equilibrium.
• Soil classification;
• Atterberg's limits:
  Liquid limit, plastic limit, shrinkage limit, plastic index, clay activity index, plasticity chart, determination of liquid limit by Casagrande's spoon and cone penotrometer, determination of plastic limit;
• Soil elasticity:
  Young's modulus, Poisson's coefficient, shear modulus;
• Mohr's circle:
  Principal directions;
• Shear strenght:
  Coulomb failure line, soil friction angle, cohesion, Mohr-Coulomb failure criteria;
• Soil strains:
  Consolidation, compaction
• Soil shear testing in laboratory:
  Triaxial test (CD, CU, UU), direct shear test;
• Soil shear testing in situ:
  CPT and SPT;
• Lateral earth pressure:
  Active, passive and at rest condtions according to Raking and Coulomb theories;
• Slopes stability:
  Stability of unfinite slope for cohesionless soils and cohesive soils, stability of finite slopes,
• Shallow foundations:
  Failures of shallow foundations, bearing capacity of soils with Terzaghi's formula, safety factor calculation of shallow foundations.
• Design of sheet piles and gabion walls

Exercises (24 hours):

• Soil sampling:
Soil samples will be collected in the area of Azienda Agraria located at Ozzano Settefonti

• Measurement of Atterberg's limits;
• Slope stability:
  Introduction to SSAP software;
• Design of retaining walls:
  Design of gravity walls, gabions, sheet piles and cantilever walls with MS Excel;

Readings/Bibliography

• PDF notes provided by the teacher.
• J. Facciorusso – Dispense di Geotecnica – Università di Firenze download link: http://people.dicea.unifi.it/johannf/?page=support_geot.
• John Atkinson - Fundamentals of ground engineering - CRC Press.
• Whitlow, Roy-  Basic soil mechanics - Longman, 1990.
• Budhu, Muni - Soil mechanics and foundations - John Wiley & Sons, 2008.
• Piergiuseppe Froldi - Dissesto idrogeologico e stabilità dei versanti. Consolidamento dei pendii con palificate. Analisi e progettazione - Maggioli Editore, 2015.

Teaching methods

Lectures in class, in soil mechanics laboratory and in computer laboratory.

Assessment methods

The course is a module of "Agro-Forestry Hydraulic Systems" together with the course of "Hydraulic Agro-Forestry". Consequently, the final assessment will be the average value of the single assessment of each course.

For this course the assessment is composed of the evaluation of three different tests:

• Oral exam (up to 10 points):
  to the Student will be asked three questions about the topics.
• Evaluation of a project (up to 18 points):
  slope stability evaluation and design of the retaining structures for the slope stabilization.
• Review of the projected carried out by other students (up to 4 points).

The online exam confirmation is mandatory.

Students wishing to take the examination in English are allowed

Teaching tools

Lectures in class, soil testing laboratory and in computer lab.

Office hours

See the website of Michele Mattetti