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  • Evolution of Design and Construction Approaches in the

    Jan 01, 2016 · Today we know that full-face advancement is all the more necessary the more difficult the excavation conditions are. Memory serves to illustrate the criteria that helped define modern design and construction concepts and an example of their application for constructing a great twin tunnel (258 m2 + 258 m2 in section) in the urban area of Rome

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  • Plenary Lecture: Full Face Excavation of Large Tunnels in

    Full-face excavation of large tunnels in difficult conditions

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  • Time Dependent Deformations in Squeezing Tunnels

    excavation, when it is difficult to distinguish the "face effect" from the "time effect". This paper deals with full face excavation of large size tunnels in rock masses which exhibit squeezing behaviour. This is considered explicitly by using three constitutive models which …

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  • Methods of Tunnelling

    The full face method is normally selected for small tunnels whose dimensions do not exceed 3 m. In this method, the full face or the entire facade of the tunnel is tackled at the same time. Vertical columns are erected at the face of the tunnel and a large number of drills mounted or fixed on these columns at a suitable height as shown in Fig. 3.2.

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  • INNOVATIVE TUNNELLING CONSTRUCTION METHODS IN …

    Of the available options for conventional tunnel excavation and construction in squeezing rock (e.g. multiple headings, top heading and bench, full face), the most successful method applied in many cases is the full-face method (Figure 3). A significant advantage of this

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  • The stability of the excavation face of shallow civil and

    Full-face excavation in tunnels, even in poor grounds, is currently being used increasingly often and when used advantage is taken of the potentiality of the machines, the equipment and the large dimensioned plants to reduce the construction times, limit the costs and guarantee better safety conditions [1, 2]. An excavation face, however, can

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  • Full-face excavation of large tunnels in difficult conditions

    Full-face excavation of large tunnels in difficult conditions

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  • Six methods of tunnel construction | Gaofei

    Oct 19, 2020 · 3. Construction features of full-face method: (1) Excavation section and work space are large and interference is small; (2) Conditions to make full use of machinery and reduce manpower; (3) There are few procedures, which is convenient for construction organization and management, and improves working conditions;

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  • Full face excavation in difficult ground - Lunardi - 2014

    When full-face tunnel excavation is carried out, stresses and strains do develop in the surrounding rocks, including the "core" ahead of the advancing tunnel face.

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  • A critical review on the developments of rock support

    Sep 01, 2020 · Heavy rockburst during full-face excavation in hard grain-diorite: sp; bl; rb + sh: Campegno roadway tunnel (D ~ 12 m) (Italy) Highly anisotropic stress conditions (k ~ 0.3), with principal stress inclined, parallel to the surface slope. Occasional rockburst in …

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  • Face stabilization of deep tunnels using longitudinal

    Full-face excavation of a tunnel is currently preferred, even in poor rock masses and in difficult conditions. In this way, it is possible to take full advantage of the potentiality of the machines and large size plants. The problem of face stability, however, is fundamental for the stability of …

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  • Time Dependent Deformations in Squeezing Tunnels

    excavation, when it is difficult to distinguish the "face effect" from the "time effect". This paper deals with full face excavation of large size tunnels in rock masses which exhibit squeezing behaviour. This is considered explicitly by using three constitutive models which …

    Learn More
  • FROM THE ADECO-RS APPROACH TO THE TUNNELLING - …

    1. full face tunnel advance always, especially under difficult stress-strain conditions: due to its peculiar static advantages and because large and powerful machines can be profitably used in the wide spaces available, it is in fact possible to advance in safety with excellent and above all constant advance rates

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  • (PDF) Full face excavation in difficult ground

    12 rows · Jun 01, 2016 · Of the available options for conventional tunnel excavation (e.g. multiple headings, top heading

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  • Reinforced Tunnel Excavation — FLAC3D 7.0 documentation

    Nov 02, 2021 · The excavation was progressed by 1.5 m per step and an HEB 180 shotcrete was installed after each excavation step. The tunnel invert was setup using the HEB 220 shotcrete after the excavation face was about 9 excavation steps. Shell elements with a linear elastic behavior are used to model the shotcrete at the tunnel wall, tunnel face and invert.

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  • Full-face excavation of large tunnels in difficult …

    Full-face excavation of large tunnels in difficult conditions

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  • METHODS OF TUNNELING IN ROCK - KPSTRUCTURES

    Nov 26, 2020 · At Present Techniques Shield And Tunnel Boring Machine (TBM) Are Popular And Well Suited For Full Face Excavation In Different Ground Condition And Various Shapes And Size. Tunnel Boring Machine This Method Useful When Diameter Less Than 6 m And Face Area Less Than 19 m 2 As Further Increase In Diameter And Area Result In Difficult Construction

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  • An assessment on the inner lining need for a large-span

    Mar 15, 2021 · Barla G (2016) Full-face excavation of large tunnels in difficult conditions. J Rock Mech Geotech Eng 8(3):294–303. Article Google Scholar 5. Sharifzadeh M, Kolivand F, Ghorbani M, Yasrobi S (2013) Design of sequential excavation method for large span urban tunnels in soft ground- the case of Niayesh road tunnel Project.

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  • tunnels and underground excavations - Tunneling techniques

    tunnels and underground excavations - tunnels and underground excavations - Tunneling techniques: Tunnels are generally grouped in four broad categories, depending on the material through which they pass: soft ground, consisting of soil and very weak rock; hard rock; soft rock, such as shale, chalk, and friable sandstone; and subaqueous. While these four broad types of ground condition require

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  • Full analysis of tunnel construction methods | Gaofei

    Oct 09, 2021 · Construction features of full-face method: (1) Excavation section and work space are large and interference is small; (2) Make full use of machinery and reduce manpower if possible; (3) There are few procedures, which is convenient for construction organization and management, and improves working conditions; (4) Excavation takes shape at one

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