Description
Microtunnelers are machines used to excavate small tunnels, generally from a few centimetres to a few metres in diameter. Designed for specific applications such as the installation of pipes, cables or other underground infrastructures, these machines offer an efficient and precise alternative to traditional digging methods. Microtunnelling machines are equipped with drill heads adapted to the material being excavated, minimizing surface disturbance while ensuring safe, precise excavation. They are widely used in civil engineering and public works to create tunnels under roads, rivers, railroads and other obstacles, reducing disruption to the environment and local communities.
The range
In microtunnels, precast concrete rings are lowered from the access shaft. For long drives, the thrust becomes too significant, posing a risk of either breaking the rings or slowing down the advance of the microtunneling machine. Intermediate stations are then set up and utilized to relay the thrust forces exerted at the starting shaft.
To protect the intermediate stations and ensure their sealing, the HBW NewGeneration provides:
- Resistance to washout (water, mud, etc.) and pressure
- Limited impact on the environment
- Approval from tunneling machine manufacturers
To reduce the thrust forces of microtunneling machines, it is also possible to use bentonite additive with a viscous and lubricating polymer to fill the annular gap: TFA 34. This preparation provides significant slippage, thereby considerably reducing friction between the soil and the machine's extrados. The decrease in the thrust force on the precast concrete rings is ensured by the use of diluted TFA 34.
