MSc_Design & construction of underground works

MSc inDesign and Construction of Underground works’

 

The MSc course in ‘Design and Construction of Underground works’ explores various design and construction techniques applied in tunnelling and underground construction works. It offers the students a deep understanding of the theory of geomechanics and its application to technically complex underground works that include significant geotechnical uncertainty.

The Geotechnical Department is participating in this interdisciplinary course, which is provided with the cooperation of the School of Mining and Metallurgical Engineering, the School of Civil Engineering and the School of Rural and Surveying Engineering, with the following courses:

YE3. ‘Geotechnical instrumentation and immediate support measures in underground works’

This course sets out the basic principles of geotechnical field monitoring and instrumentation. Monitoring methods are described and the technical literature is given for instruments recommended for monitoring groundwater pressure, deformations, total stress, and load and strain in structural members. Instrument calibration, installation, and ways of data collection, processing and interpretation are examined in detail. By using case studies the role of geotechnical instrumentation on various types of construction projects is investigated. Behavior of the rock mass surrounding an underground excavation, mechanical response of tunnel face, and underground excavation support methods. Stresses around underground openings and relaxation of surrounding rock due to support. Response of struts, frames – lattice girders, concrete – shotcrete – additives to loading. A major part of the course takes place in the laboratories of Soil Mechanics and Steel Structures at the School of Civil Engineering and the laboratory for Tunneling at the School of Mining & Metallurgical Engineering.

Instructors: V.N. Georgiannou, P. Νomikos
Assistants: X. Lignos,G. Papadonopoulos, P. Yiouta-Mitra,  Ε.-Μ. Pavlopoulou

YX1. ‘Engineering Geology for Underground Works’

 Geology of tunnels and underground works. The importance of the geological model (lithology, tectonics, weathering, hydrogeology) for the design of tunnels. Crossing active faults. Engineering geological characteristics of principle rocks and formations. Geotechnical classification of rocks and rockmasses. Tutorials on engineering geological mapping and construction of geological cross sections for tunnels under different scale maps. From the geological model to the rock model and the assessment of mechanism of failures of the assessed ground types. Stress and structurally controlled failures. Wedge failure analysis. Landslide and tunnel portals. Groundwater and tunnel inflows. The course includes a field trip, which is mandatory for the MSc diploma.

Instructors: K. Loulassakis, V. Marinos
Assistant: P. Tsaggaratos

YX2. ‘Design of Underground Works’

Selection of design parameters. Qualitative and quantitative characterization of a geomaterial (soil, intact rock, rock mass, rock discontinuities). Strength and deformability of rocks-rock masses. Failure criteria. Wedge support design in structurally controlled failures. Estimation of squeezing phenomena in stress induced failures. Tunnel support type and element selection.  Rock mass classifications in tunnels (Terzaghi, RMR, Q, GSI) and empirical design. Stress and deformation distributions around deep and shallow tunnels under elastic or elasto-plastic conditions. Rockmass loosening pressures, convergence-confinement curves, principles of the NATM method, temporary tunnel support and interaction with rockmass. Mechanical tunnelling methods (TBM). Pressures on the permanent lining of tunnels. Observational method in tunnels by geotechnical monitoring. Special support in rockburst phenomena, karst, swelling ground, tectonically active areas. Control of groundwater in tunnels. The course includes a field trip, which is mandatory for the MSc diploma.

Instructors: P. Matinos, V. Papadopoulos
Assistants: Ph. Chortis, D. Georgiou, K. Papadopoulou

EE1. ‘Computational Methods of Analysis of Underground Structures’

Analytical solutions are derived for the elastic–plastic stresses and strains around a circular tunnel. Tunnel design considering the stress release effect, using convergence-confinement methods to determine the stress and displacement of the tunnel while considering the counter-pressure curve of the rock mass, the stress release effect, and the interaction between the tunnel lining and the rock surrounding the tunnel.

Instructor: M. Kavvadas
Assistants: D. Georgiou, Ph. Chortis

EE4. Seismic Design of Surface and Underground Geotechnical Structures

This post-graduate course has the following themes: 1. Introduction to Geotechnical Earthquake Engineering. Basic elements of engineering seismology, with emphasis on strong ground motion. 2. Single degree of freedom structural vibration with base excitation, elastic response spectra. 3. Seismic wave (P, S, Rayleigh, Love) propagation in homogeneous and inhomogeneous soil. 4. Seismic design of underground tunnels and pipelines against seismic waves and permanent ground displacements. 5. Soil amplification (or de-amplification) of seismic ground motion with analytical and numerical methods. Practice with dedicated software. 6. Seismic design of retaining walls with the Mononobe-Okabe method (pseudo-static design) and with Richards-Elms (allowable displacements). 7. Topography effects and seismic design of soil and rock slopes. 8. Liquefaction, with emphasis on assessment methods and on its effects on Civil Engineering works. Description of ground improvement methods and methods for mitigating the effects of liquefaction.

Instructors: G. Bouckovalas, A. Papadimitriou
Assistants: J. Tsiapas, K. Mpazaios, L. Tsantilas