Solutions for Conventional Tunnelling
Conventional Tunneling or excavation by using the drill and blast method or any other mechanical excavator (except full face TBM) can be a complex process.
Conventional tunnels that are constructed with spray concrete are based on a temporary sprayed concrete lining to stabilize the opening after excavation. This also contains short to medium-term loads. When this lining is fully stabilized, a permanent cast in place concrete lining is installed to contain long-term loads, and provide durability and water tightness. Bekaert Maccaferri Underground Solutions provides innovative and state-of-the-art solutions for each stage of tunnelling construction:
- Steel fibres and macrosynthetic fibres for temprary lining
- Steel fibres for final lining
More than 100 precast segment project references available worldwide, using our fibres. Take advantage of our expertise and contact us for a detailed list!
Temporary spray concrete
The purpose of the primary support is to stabilize the underground opening until the final lining is installed.
When shotcrete is sprayed on a rough ground surface, it fills small openings and cracks. It serves as initial support and also immediate support after excavation.
Spray concrete lining (SCL)
Typically current SCL design combines spray applied waterproofing membranes with spray concrete secondary lining. The design approach for all the permanent sprayed linings, including the primary layer, maximize the use of robotics and mechanics that are capable of producing high quality product.
Final lining – shaft lining – cast in place
When the temporary sprayed concrete lining has fully stabilized, a permanent cast-in-place concrete lining is installed to contain long-term loads, and provide durability and water tightness. The final lining has to sustain a large number of influences from the ground, from the construction activities, through utilization.
The permanent tunnel lining has to be dimensioned both in static and constructional terms.
The use of an automated dosing system ensures the accurate quantity of fibres in each batch of concrete.
The dosage feeder is delivered ready for use.
It contains all components necessary for power attachment and weight control.
Bekaert Maccaferri Underground Solutions is your privileged partner for the selection of the right fibre dosing equipment; including installation assistance.
Depending on the fibre type and the required dosage rate, we can recommend and provide either rental or sale solutions to our customers.
Benefit from our full service
1. For the concrete mix design, we take into account all relevant standards, as well as the specific load bearing requirements of your tunnel project. This will result in a specific steel fibre dosage tailored to your project, which guarantees the most economical and qualitative result.
2. Dramix® steel fibres are submitted to severe quality control according to international standards, including ISO 9001 and ISO 14001.
3. On top of the steel fibre quality control, dedicated tests for the entire steel fibre concrete mix are performed in controlled testing labs. We have our own concrete lab available to support you.
4. Thanks to our worldwide network, we are able to offer on-site support virtually anywhere. We also offer dedicated dosing equipment, which allows contractors to save time and work with the highest precision.
5. Our global experts bundle many years of tunnel construction experience. They keep a close eye on the latest developments in the field and regularly contribute their knowledge and opinion to the experts’ community.