Geomechanics

obligatory courses

The student should possess knowledge in:

- geodynamic processes,

- ability to recognize minerals and rocks,

- ability to map and interpret thematic maps,

- numerical modelling,

- fundamentals of statistics.

Geomechanical properties of rocks and rock massifs. Systems of indexes used to describe rock massif properties (RQD, Q, GSI, JCR). Types and range of stability threats, range of geoenvironmental transformation of rock massifs and problems of integrity in surface objects. Stages and aims of recognizing surface and underground geological-engineering conditions. Geomechanical properties of rock massifs and rocks. Primary and secondary stress. Fundamentals of elasticity, plasticity and brittle fracturing. Fundamentals of assessing stress state around underground engineering excavations. In situ and drillcore investigations, ‘breakout’ method, strength and ultrasonic laboratory investigations. Subsidence basins above mine excavations, depressions, floodings. Technical methods of preventing natural and anthropogenic hazards in rock massifs on the surface, in the sub-surface zone and on large depths. Geothermal energy.

Lecture schedule:

1. Tasks of geomechanics. Interdisciplinary character of diagnoses, prognoses, expertises and projects resulting from complex geological analysis. Surface and underground engineering objects. History and examples of constructing contemporary and historical objects.

2. Geomechanical properties of rocks and rock massifs in situ. Geological variability influencing geomechanical assessment of massif properties. Global and country scale engineering conditions of past, contemporary and future investment requirements. Development of theoretical knowledge, techniques and technologies.

3. Analysis of the intermittency of a rock massif. Fractures. Roughness. Investigations in the field, in boreholes and in underground research laboratories. Geological, engineering and theoretical systems of classifying massif intermittency. Guidelines of PN, EN and ISO norms. Generally accepted, classical systems of index characteristics of rock massif properties (RQD, RM, GSI, JCR) – Bieniawski’s, Barton’s, Hoeck’s and Brown’s classifications.

4. Types of engineering objects in rock massifs. Subdivision of methods of ore exploitation and their requirements with regard to rock massif stability. Types and scale of stability threats and scale of geoenvironmental transformations in the rock massif around underground objects and problems of integrity in surface objects.

5. Design methodology and stages. Stages and aims of recognizing surface and underground geological-engineering conditions. Application of remote and direct mapping techniques, geological-engineering surface and underground surveys, acquisition of rock samples, core sampling, preparation of schedule of destructive and non-destructive laboratory investigations.

6. Geomechanical properties of rock massifs and rocks. Assessment methods. Predictions of relationships between physical properties of rocks in natural and artificial conditions on the surface, in shallow excavations and at large depths. Design parameters. Application of various methods of their assessment depending on the type of engineering object (construction resources, hydrotechnical objects, underground storages of waste and resources, historical stone monuments.

7. Primary and secondary stress. Application of simulation methods to assess massif deformation in underground and surface mining. Fundamentals of elasticity, plasticity and brittle fracturing. Fundamentals of assessing the stress state around underground engineering excavations. Deformation zones. Surface depression basins.

8. Research possibilities and methods of assessing geological stress in rock massifs. Theoretical background. In situ and drillcore investigations, hydraulic fracturing, ‘breakout’ method, strength, ultrasonic and structural laboratory investigations.

9. Natural and anthropogenic geological-engineering threats and their effect of the conditions of massif reclamation in long- and short-term conditions. Problems of mutual effects between surface and underground infrastructure. Subsidence basins above mine excavations, depressions, floodings. Old excavations and other traces of historical mining. Recognition methods. Distinguishing safety zones and endangered zones.

10. Technical methods of preventing natural and anthropogenic threats in rock massifs on the surface, in the sub-surface zone and at large depths.

11. Problems of adaptation, revitalization and conservation of underground and surface mining infrastructure, utilization of abandoned boreholes, determination of the requirements used in application to industrial, communal, monumental and research cases (URL). Resources of geothermal energy in rock massifs. Methods of their utilization in relation to natural rock massifs, abandoned underground mines and mining heaps. Essential parameters of geomechanical assessment.

On completion of the course, the student:

- knows methods of field and laboratory determination of strength properties of rocks and rock massifs,

- makes assessment of a rock massif,

- calculates the physical parameters of rocks,

- calculates the strength to uni-axial stress and Young’s modulus,

- recognizes the threats of affecting the stability of natural and artificial objects located on a rock basement,

- knows the basic mechanisms of degradation in modern and ancient stone monuments and preventive measures,

- determines integrity and calculates the changes,

- understand deterioration mechanisms and describes them using a mathematical apparatus.

Requirements for the final written examinations:

- knowledge of material presented during the lectures,

- knowledge of material acquired during classes.

Final written examination encompassing knowledge acquired during lectures and classes.