Tunneling and Mining

Applications typiques

Soft-eye PRF wall for easy penetration of TBM through retaining walls.

Pour le boulonnage du toit et des murs dans les applications temporaires et permanentes

Nos solutions

Innovative PRF solution for efficient tunnel excavation ASTEC™ PRF combination bolt is a unique and innovative Glass Fiber Reinforced Polymer solution precisely designed by Dextra. In unconsolidated excavation areas, like steel bolts, PRF Combination Bolts can be automatically installed by a jumbo machine or manually installed. Thanks to the characteristics of the PRF material, Combination Bolt can easily be cut by common excavation equipment, which makes the product an ideal solution for temporary application for tunnel excavation projects. Eurocode 2, BS 8110, DIN 1045, ACI 318, IBC, AASHTO, ASME Sec III Div 2.

Tunnel breakthrough made easy with PRF rebar ASTEC Soft–Eyes allow the penetration of Tunnel Boring Machines (TBM) through parois moulées and secant piles. This unique technology uses cuttable Glass Fiber Reinforced Polymer (PRFV) Armatures as an advantageous replacement for conventional steel rebars. The Soft-Eye technology was developed by Dextra in 1996 and successfully implemented for the first time on Bangkok MRT subway stations. The Soft-Eye technology has since become a standard concept in the design of launching/receiving shafts and subway stations. We have successfully supplied over 500 soft-eyes on all continents. Dextra offers an integrated turnkey solution that includes design, optimization, manufacturing, logistics, and on-site training.

Les systèmes de poutres en treillis GEOTEC sont des cadres en acier courbés tridimensionnels légers composés de barres principales, de barres secondaires, de plaques de connexion, de plaques de base et de raidisseurs.

The lattice girder can provide immediate support for Creusement de tunnel environnements.

Le rayon de courbure est conçu sur mesure pour répondre aux exigences de chaque projet.

VOUTE PARAPLUIE

Un système de pré-support pour les terrains fragiles

Le système de tuyaux parapluie GEOTEC™ est un pré-support dans des conditions de sol meubles et faibles. Le système comprend des tuyaux en acier installés à partir de la face du tunnel pour former un toit afin de stabiliser les têtes du tunnel. La répartition de la charge dans le sens longitudinal peut réduire la déformation lors des excavations.
Le mécanisme de support de la méthode du tube parapluie consiste à stabiliser le front de taille de l'excavation dans les directions transversale et longitudinale par une zone renforcée en forme d'arc. Le système de soutien peut être divisé en trois aspects différents :
Support radial Support longitudinal
Subdivision des espaces ouverts de la zone non supportée

BOULON ACIER A ACTION COMBINEE

Immediate and permanent rock bolting solution GEOTEC™ steel combination bolt is suitable for the most stringent requirements. A mechanical bolt combined with a corrugated pipe and a double grout layer all along the tendon to provide both high bonding and protection against corrosion (similar to Double Corrosion Protection / DCP). It is initially installed for immediate support by the use of an expansion shell, to be fully grouted at a later stage allowing it to be classified as permanent application. bent Armatures bars while being simpler and faster to install.

Cuttable mining anchor GEOTEC™ PRF solid rock bolt is a rock-bolting system based on a fully threaded PRFV tendon. It is specially designed for the following applications: Face-bolting and temporary applications: The cutability of PRF makes it the ideal solution for face bolting or any other Creusement de tunnel/mining application where further excavation is required. Cohesive soil & hard rock. GEOTEC PRF is installed into pre-drilled holes. Installation with grout or with resin cartridges.

Forage, injection et ancrage en un !

GEOTEC Steel self-drilling rock bolt is a rock-bolting system based on a fully coarse threaded hollow bar.
Il est particulièrement recommandé pour les applications suivantes :
Boulonnage du toit et des murs.
All ground conditions. GEOTEC self drilling rock bolts do not require pre-drilling a hole, therefore making it usable even in soft rock conditions.
Installation with grout. The hollow steel anchor rod also acts as a grouting pipe to ease setup. For non-grouting applications, please refer to the mechanical anchor or expandable friction bolt.
Applications temporaires ou permanentes. Avec revêtement époxy en option disponible pour les applications permanentes.

PRF hollow rock bolt

ASTEC PRF hollow rock bolt is a rock-bolting system based on fully threaded hollow PRFV bars. It is specially designed for the following applications:

Boulonnage frontal et applications temporaires : The cut-ability of PRF makes it the ideal solution for face bolting or any other tunneling/mining application where further excavation is required.

Cohesive soil & hard rock conditions: ASTEC is inserted into a pre-drilled hole. For a non-cohesive soil environment, refer instead to PRF Self-Drilling Bolts.

Pose avec coulis : The hollow PRFV anchor rod also acts as a grouting pipe to ease installation.

Tunnels et exploitations minières