GT – Technical Committee

Working groups are the backbone of the Association

AFTES working groups (GT) are set up to address thematic needs identified by the Association. Most report to a Committee, which is responsible for coordination between the various WGs within its scope, and for approving their deliverables.

Each GT is led by an AFTES member. All members are free to contribute according to their possibilities, availability and expertise, subject to approval by the group’s animateur. These groups produce documents and recommendations relating to the assigned theme, which are then submitted to the Committee for approval prior to publication (in French, and generally also English).

Decisions relating to the creation of new working groups and the appointment of GT animateurs are made jointly by the parent Committee and the Executive Council.

There follows a brief presentation of the Working Groups currently active, as well as the Committees to which they report, their animateurs and the means of contacting them for more information.

Technical Committee ‐ GT 3 ‐ Use of explosives

This Working Group deals with all matters relating to the use of explosives for excavating underground structures, including equipment and resources, operating conditions and vibration effects, for example.

 

Most recent Recommendation: Vibrations generated by mine blasts: determination of vibration thresholds during preliminary project studies
Theme: Conventional excavation
Animateur: Loïc Thévenot
Vice animateur: Sophie Duclos

>> Go to group

Technical Committee ‐ GT 4 ‐ Mechanised tunnelling

This Working Group deals with all matters relating to mechanised tunnelling. It strives to capitalise feedback from mechanised work sites, and issues Recommendations regarding the use of such techniques.

 

Recent publications:
– TBM data sheets: Project information sheets relating to various mechanised work sites (143 sheets to date)
– Review of developments in TBMs and their capabilities over the period 2000-2019
– Recommendation relating to the choice of confinement method
Theme: TBMs, shields and segments
Co-animateurs: François Renault and Magali Schivre

>> Go to group

Technical Committee ‐ GT 6 ‐ Sprayed concrete

This Working Group is concerned with the means, equipment and conditions of use of sprayed concrete as excavation support.

 

Last publication : Recommendation for drafting specifications relating to wet process sprayed concrete for support and lining in underground structures
Publication pending :WG6 is curently working on dry process sprayed concrete
Theme: Conventional support and lining
Animateur: Catherine Larive
Vice Animateur: Christine Thuaud

>> Go to group

Technical Committee ‐ GT 9 ‐ Water Protection and drainage

This Working Group deals with issues relating to sealing processes used for underground works, including equipment, resources and operating conditions.

 

Publication pending: Protection of external sealing and drainage of underground structures.
Theme: Grouting and waterproofing
Animateur: Stéphane Petit
Vice animateur: David Chamoley

>> Go to group

Technical Committee ‐ GT 12 ‐ Health, safety and working conditions

The purpose of this Working Group is to issue recommendations relating to health, safety, and working conditions at above-ground and below-ground construction sites for underground structures.

 

Recently published Recommendation: Organisation of emergency services and related resources during underground works.
Pending Recommendation: Safe movement of personnel and equipment during underground works.

Theme: Safety, quality, logistics & the environment
Animateur: Pascal Sergi

>> Go to group

Technical Committee ‐ GT 16 ‐ Settlement and vibrations caused by excavation

This Working Group examines the technical and contractual implications of settlement and vibration caused by the excavation of underground structures.

 

Recently published Recommendation: Effects caused by excavation on neighbouring structures in the design and construction of underground works.
Short-term outlook: Research into settlement estimation techniques and the methodology applicable to intrinsic sensitivity studies.

Theme: Ground conditions and soil-structure interaction
Animateur: Didier Subrin

>> Go to group

Technical Committee ‐ GT 18 ‐ Precast concrete segments lining

The role of this Working Group is to issue recommendations concerning the design of prefabricated reinforced concrete lining segments used in mechanised tunnelling. These recommendations are intended to supplement regulatory provisions where necessary.

 

Work in progress: Update to the recommendation on the design, sizing and production of prefabricated lining segments in accordance with the latest versions of the Eurocodes.

Theme: TBMs, shields and segments
Animateur: Pascal Guedon

>> Go to group

Technical Committee ‐ GT 19 ‐ Monitoring

The GT 19 deals with the monitoring and condition assessment of underground structures.

 

Published Recommendation: GT19R2F1 : Méthodes d’auscultation des ouvrages souterrains – 2005
Next Recommendation: Pending

Theme: Monitoring
Animateur: Benoit Bertrand
Vice animateur: Martin Beth

>> Go to group

Technical Committee ‐ GT 20 ‐ Design and dimensioning of sprayed concrete

The GT 20 aims to develop a recommendation on the design justification and dimensioning of shotcrete ground support systems, with particular focus on an AFTES Type 2 shotcrete lining. The objective is to update the existing recommendation on this topic (GT20R1F1 2000).

 

Ongoing recommendation: Update of the existing recommendation on this topic (GT20R1F1 2000).

Theme : Ground support and linings
Animateur : Christophe Jassionnesse
Co-animateurs :

>> Go to group

Technical Committee ‐ GT 23 ‐ Steel ribs supports

This Working Group, currently being launched, aims to update the existing recommendation on the use of steel ribs in underground construction. In addition to the design and sizing of these support systems, it will include recommendations related to safety during the handling and installation of these steel ribs.

 

Theme: Conventional support and lining systems
Animateur: To be announced
Co-animateur: To be announced

>> Go to group

Technical Committee ‐ GT 24 ‐ Geotechnical investigations

This Working Group covers all aspects of geotechnical surveying applied to underground works, including technologies, scouting, forward probing and the role of surveys in the construction process.

 

Pending Recommendation: Geological, hydrogeological and geotechnical surveys required for the design of underground structures.

Theme: Ground conditions and soil-structure interaction
Animateur: Cédric Gaillard

>> Go to group

Technical Committee ‐ GT 27 ‐ Ventilation of underground structures under construction

This Working Group deals with the design and implementation (including equipment and resources) of ventilation systems for underground structures under construction in accordance with regulations on working conditions and environmental protection.

 

Publication pending: Update to the Recommendation on ventilation of underground structures under construction.
Theme: Safety, quality, logistics & the environment
Animateur: Alain Mercusot
Vice animateur: Elisa Béraud

>> Go to group

Technical Committee ‐ GT 30.2 ‐ Numerical modelling

This working group focuses on the application of numerical modelling to the design and study of tunnels and underground works.
Ongoing recommendation : Applied numerical modelling of underground structures

Theme : Design and Analysis of Underground Structures
Animateur : Laetitia Pavel
Co-animateur : Lauriane Bouzeran

>> Go to group

Technical Committee – GT 32 – Risk management

This Working Group deals with recommendations on the principles and mechanisms for taking into account the consequences of schedule variations arising from execution difficulties and/or external events.

 

Recommendation under preparation :
Theme: Contracts, Planning, Socio-economic and Legal Aspects
Animateur: Elena Chiriotti
Co-Animateur: Emmanuel Humbert

>> Go to group

Technical Committee ‐ GT 35 ‐ Excavated materials

The role of this Working Group is to issue recommendations intended to promote resource conservation and sustainable development practices relating to management of materials excavated from underground works carried out using either conventional or mechanised methods.

 

Published Recommendation: Management and use of excavated materials.

Theme: Safety, quality, logistics & the environment
Animateur: Jacques Burdin

>> Go to group

Technical Committee ‐ GT 37 ‐ Fire resistance of tunnels

After initially addressing fire resistance in road tunnels, this Working Group is now examining the case of railway tunnels.

 

Pending Recommendation: Consideration of fire risks in the structural design of railway and guided transport tunnels

Theme: Maintenance and rehabilitation
Animateur: Alain Bochon
Vice animateur: Bérénice Moreau

>> Go to group

Technical Committee ‐ GT 45 ‐ New digital technologies

This Working Group was established to create a permanent forum for discussing issues relating to the development of BIM in the underground construction field in France and internationally, and to assert the role of AFTES in the MINnD national project in France, and in ITA-AITES WG 22.

 

Theme: Planning, socio-economic and legal aspects

Animateur: Florent Robert

Vice animateur: Nataliya Dias

>> Go to group