Microtunnelling


Pipe jackings with closed shield (microtunnelling) for internal diameters of 400 mm to 4000 mm. Applicable below groundwater level through sand, loam or clay soil or through gravel and rock formations.

The jacking pipes are pressed simultaneously with the boring process from a starting pit into the subsoil. The technique can be used at underground crossings of rivers, roads, wildlife areas and other infrastructure. Special applications are pipe roofs and outfalls.

Technique sheet for microtunnelling

References


NAESTVED - DENMARK


Client: NK-Forsyning A/S Spildevand
Main contractor: C. Holbøll & Sønner Entreprise A/S
Sub contractor: Smet-Tunnelling nv
Execution: 2016-2017
Technique: 4 pipe jackings with closed front

Project Sheet

AVN 1600 mm, L = 96 m, Soil: hetrogenities, Crossing of a road
AVN 1600 mm, L = 302 m, Soil: hetrogenities, Crossing of a nature reserve
AVN 1600 mm, L = 399 m, Soil: hetrogenities, Crossing of a nature reserve
AVN 1600 mm, L = 327 m, Soil: firm clay, Crossing of a nature reserve


BOTTROP - GERMANY


Client: Emschergenossenschaft
Main contractor: Arge EZG III Bottrop (Eiffage – Smet-Tunnelling)
Execution: 2020
Technique: Pipe jacking with closed front? Ø 1200, lenght: 192m

Project Sheet

The jacking started from the water treatment plant
(Pumpwerk Piekenbrocksbach) to an existing secant pit.
A jacking in the marl at a depth of +/-15 m.
A jacking under the Piekenbrocksbach.
Difficulties:
• Small set up space
• Deep wells (15m to 17m)
• Eccentric storage of the drill shield in old, existing secant pit


HOLZBACH


Client: Emschergenossenschaft
Main contractor: Arge Wittfeld – Smet – Eiffage Infra Vortriebstechnik
Subcontractor: Sanimet
Execution: September ‘19 – March ‘21
Technique: Pipe jacking with closed front

Project Sheet

Holzbach BA1:
DN1600 : 211m + 208m + 117m + 205m + 499m + 357m
DN800 : 120m
DN700 : 77m + 78m + 77m + 79m
DN600 : 25m

Holzbach BA2:
DN2800 : 290m
DN2400 : 160m
DN2200 : 230m
DN1200 : 50m
DN800 : 38m


HELSINGE (Denemarken)


Client: Gribvand Spildevand sa
Engineer: COWI as
Main contractor: Smet-Tunnelling nv
Machine: AVN
ID-OD: 2,500 – 3,000 mm
Lenght: 1.100 m
Execution: July 2012, October 2012

Project Sheet

A tunnel going underneath the city of Helsinge including the crossing of 15 houses, 8 roads and 2 parking areas.


SINT-JANS-MOLENBEEK (Mirtenlaan)


Principal: BIW
Main Contractor: Sodraep
Execution: November, 2010-March, 2011
Machine: AVN
Pipes: reinforced concrete
ID-OD: 3,000 – 3,480 mm
Length: 371 m

This pipe jacking was carried out with Benor-approved concrete pipes of 3  m long weighing 18 tonnes. The boring contains a spatial bend with a radius of 500 m (vertical) and 600 m (horizontal).


ANTWERPEN (Van Cauwelaertsluis)


Principal: BAM
Main Contractor: Roegiers
Execution: 2011
Machine: AVN
Pipes: reinf.  concrete with steel core
ID-OD: 3,000 – 3,480 mm
Length: 165 m and 220 m

Project sheet

The renovation of the lock complex Van Cauwelaertsluis in the port of Antwerp featured a double pipe jacking underneath both locks. The biggest challenge in this regard lay in the departure and arrival levels at a depth of no less than 30m below ground level. Both pipe jackings are in line and serve as tunnels for pipes, with optional inspection capability, for all sorts of cables and pipes.