Week 3: Rock Mechanics

In true sense, it was a ROCKing weak. Prof Barbera started with brilliant comprehensive lectures on the basics of rock mechanics covering the geotechnical models, discontinuities, mechanical characterization of intact rock and rock mass and classification. She further took us to the Politecnico di Torino Geotechnics and Rock Mechanics laboratory DIPLAB (DIsaster Planing LABoratory) where we saw an army of triaxial apparatus for different requirements of tests apart from other soil and rock testing equipment. What intrigued us was the direct shear test machine for snow which was developed in PoliTo. We were also trained in DIPS software in the LAIB practising on a real time data provided by Prof Barbara. Prof Migliazza focussed on moderately fractured and jointed rocks in her lecture on unstable block analysis. She covered discontinuity surveys by classical methods and most advanced methods like Digital Surface Modelling by photogrammetry, laser scanner etc., by showing us results from actual projects comparing both systems and procedural approach of advanced methods.

Further Dr Russo introduced us various Geomechanical classifications studies on rock mass and their application in prediction of excavation behaviour and design choices and calculations. His lecture was beautifully structured into step-by-step methods of classifications by different authors from Terzaghi (1946) to Palmstrom (1995)’ He also explained us the most inclusive and widely used method in Geodata for Simplified approach for a preliminary setting of excavation behaviour formulated by him, GD Classification Rosso 2007 by involving us in classroom exercise. His lecture also presented a cross-checking of the reliability of the multiple graphs by documented Case-Histories. He shared with us alarming videos showing different types of rockbursts from various tunnelling sites around the world.

This week though being intensive and exhaustive ended with another brilliant lecture from where he introduced us different types of supports for conventional tunnels laying a great foundation for the lectures to follow. Prof peila discussed different types of rock bolts and shotcrete and the necessary aspects to take care while designing these support systems.

Week 2: General aspects and Soil Mechanics

Prof Claudio Oggeri, a proficient in geomechanics started the week by quoting ‘In a site investigation, if you do not know what you should be looking for, you are not likely to find much of value’ stressing on the importance of planning the investigations for different underground works and covering various geological measurements.

Prof Corrado Fidelibus from Politecnico di Bari took us on an intensive ride to introduce the basics but in a very different perspective, that of a soil particle. The lectures focused on Terzaghi and Navier Cauchy’s work to conceptualize hydro-mechanical aspects of soil mechanics and its relevance in tunnelling works. His lectures also covered the concepts of natural undisturbed state of stress in rocks and soils. Prof Jarre then quoted best of the examples in his lectures and won us all with his charm, ending the week on a good note.

Opening Day and Week 1

The Master’s kicked-off with a warm, welcoming and informative opening ceremony. The ceremony was graced by the director for lifelong learning of PoliTo. Prof Daniele Peila, the director of the course, welcomed all the students to the university and gave a brief of the course highlighting his expectations. There we were, from diverse backgrounds and different countries but with gleaming energies bucking up for the year ahead. It is fun and challenging to be back to the classroom after a while for many of us.

Listen to the director and students here about the session

The lecture on general aspects of tunnelling and guidelines for underground structures design marked the beginning of the course and was a high-on-energy and filled with examples of tunnelling projects from around the world. This is what Prof Peila brings to you, always!! We were advised to be open in our approach always while practicing. The week was then aimed to introduce the geological and geophysical aspects of tunnelling from investigations to the design considerations to the risk aspects induced by geology while tunnelling. While Dr. Soldo, the technical director from Geodata asked us to have a holistic and open approach, he covered geoengineering design coupled with interesting uncertainty concepts and quoting many standards and some interesting case studies. Prof Sambuelli, a well-known expert in geophysical surveys and a NatGeo geologist, covered an array of investigation methods, shared with us a ton of literature for our future reference. Prof Russo started from the basics of hydrogeology, also explaining its relevance by quoting the alarming differences in the contents of simple bottled water, ending with a thoughtful quote ‘don’t avoid water, manage it’.

2018 Upcoming edition

The new edition of the T&TBMs Master is coming soon
The call for applications will be opened in May 2017.

You can get some further information about it at the Master's official website.

WTC 2019 - Naples

T&TBMs MAS Course Final Trip

Day 1 (06/07/16):

During the last week we had the opportunity to visit some very interesting sites as a conclusion of the course.

To start with, we went to the hydroelectric power plant of Nant de Drance in Switzerland. In this site, an enlargement of the system was done in order to double the capacity of an upstream dam. In this way, by a pumping station is possible to save the energy with an efficiency of 85% in the surplus moments. The final capacity of the power plant will be 9000 MW. For the twin tube connection to the pumping station an open TBM was used with several ground treatment operations in order to cross a fault zone with water pressure up to 20 bar and with high risk of causing settlements to the arch dam. For the twin vertical shafts of 8 m dia. the raiseborer technique was utilised to drive a pilot tunnel from which the D&B muck could be removed from the bottom caverns. Steel lining was required in the most critical components of the tubing system with the highest requirements for the welding and junction systems. A very unique and impressive solution was construction of massive underground caverns for the installation of a batching plant and mechanical offices. A unique project with the highest standards and a very positive scope in one of the most beautiful alpine environment.

Students at Nant de Drance hydroelectric power plant with the extended dam at the back.

Day 2 (07/07/16):

During the next day we had the fantastic oportunity to visit Herrenknecht factory in Schwanau, Germany. The leader of the market is producing their machines in a taylor made and precise way, providing solutions for most of the underground excavation techniques and scenarios. We visited the microtunnelling and mining areas and then the TBMs section where the machines of the upcoming projects are being built. There were several EPBs, Mixshields and Rock TBMs in different phases of assembly and production. The possibility to see the separate components and study them in detail it is fundamental to understand its working principles and functioning. One of the most impressive experiences for a young tunneler, walking through this small town producing such powerfull and reliable tools. In the picture, a 15,7m dia. Mixshield TBM being assembled.

Students at Herrenknecht factory in Schwanau, Germany.

Day 3 (08/07/16):

To close the trip we went to northern Italy, in the border with Austria to visit the jobsite for the future Brenner Base Tunnel (BBT). The exploration phase was just finished on the italian side by driving an open rock TBM through the future emergency escape tube, that will be used in the future for the muck out of the excavated material up to the deposit area to reduce the impact on local roadways. The project consist of twin tubes for a high speed railway connection taking part of the South - North corridor from Naples to Helsinki. The construction should start by the end of this year as the tender is being closed at the moment. After receiving a presentation on the main features and challenges of this project by the client’s engineering company we went to visit the stretch finished as well as the underground TBMs assembly cavern in the core of the alps. Great attention is being paid in this project to the communication with the local people, by informing and giving access in order to reduce the opposition to such a possitive project for the enviroment and the community.

Underground TBMs assembly cavern for the Italian lot of the BBT.

Week 24: Jobsites organisation and Microtunnelling

During the last week of the Master course, Nicola della Valle (Tunnel Consult) held a very interesting lecture on the logistics and organisation of job sites in urban areas where the efficient use of the available spaces is a key for the tunnel excavation productivity. He presented some case studies from his vast professional experience of well and not so well organised job sites and the direct consequences in the overall quality of the tunnelling process.

Nicola della Valle and the students of the master after his lecture on Jobsites in Urban area

Going on during this week, Roberto Crova presented the case study of Torino Metro Line 1 Extension, a jobsite that we had the opportunity to visit during the last day of the course, where the space available was minimum to launch the machine in a telescopic way with the back up completely installed at the surface.

Cutterhead of the EPB machine to be used for the extension of Torino Metro line 1

Mario Patrucco from Politecnico di Torino held a fantastic lecture on safety in underground spaces, risk management and ventilation design. This was part of a five days module fully dedicated to the safety control.

Finally to close with the Master Course, Ray Sterling from Louisiana Tech University held a fantastic intensive course of three days concentrated on Microtunnelling and trenchless excavation techniques. 

Week 23: Ventilation and Safety in underground spaces II

Elena Chiriotti Tender management

Elena Chiriotti and the students after her lecture on tenders management

This week was devoted to the study of the the safety and ventilation issues by
Achille Sorlini of Telt

Achille Sorlini and the students after his lecture on safety on work sites

and by Prof. Mario Patrucco of Politecnico di Torino
Finally Prof Romano Borchiellini of Politecnico di Torino  gave a good analysis of the design issues of tunnel ventilation

Week 22: Safety in underground spaces I

This week Prof. Patrucco started the analysis of the safety issues in tunnel construction.
The topic of  use of compressed air in Tunnelling was developed by Eng. Paolo Morzone and Eng. Luca Bicchierini of Atlas Copco company

Prof. Marina Pirulli of Politecnico di Torino  developed the topic  of tunnel vs slope stability

The important case history of the Frejus tunnel was discussed by Eng. Leone of Telt

Week 21: TBM's auxiliary systems

Starting with this week, Patrizio Torta (PM&E) presented some case studies of Claims, focusing on the importance of the rights and duties of each party acting on a project. He emphasised as well on the value of a well established contract to avoid conflicts and its catastrophic consequences in economical and schedule terms.

Patrizio Torta and the students after his lecture on claims management

Fritz Grübl (PSP Consulting Engineers GmbH and University of Applied Sciences Stuttgart) held a very interesting and dynamic lecture on TBM driving and segmental lining design. As a founder member of TACS guidance systems he discussed the evolution and state of the art of this key component of the machine for its precise steering along the designed alignment. His main research topic at Stuttgart University of Applied Sciences is Segmental Lining so he presented as well the most important aspects for its design and installation. 

Fritz Grübl and the students after his lecture regarding TBM guidance and lining

From his more than 30 years experience on TBM drives, Antonio Nicola from Salini Impregilo   pointed some very interesting and crucial aspects to take into consideration for the planning and operation phases of a mechanised tunnelling project. Focusing mainly on the auxiliary and miscellaneous systems such as:

• Muck transport
• Concrete and segments transport
• Ventilation system
• Hyperbaric facilities
• Slurry treatment plant
• EPB soil conditioning agents supply
• Dewatering and water treatment plant
• Compressed air supply
• Electricity supply

Antonio Nicola and the students after his lecture on TBM miscellaneous systems

Jarre Pietro (Global) gave us another of his peculiar presentations focusing on the importance of a well established communication and the increasing importance of the GIS and BIM based softwares to improve the interoperability of the parties involved in the design and construction process. Technology provide us with powerful tools that must be exploited to enhance the logistics, monitoring and communication during the life span of a project.

Pietro Jarre and the students after his lecture on GIS and BIM use for communication.