Steel fibres have a number of uses in the construction of tunnels with concrete lining. They can be incorporated in the temporary lining which is generally a sprayed lining procedure (see above). They can also be used in the final lining phase where they are incorporated in the cast in situ lining or in the pre cast tunnel segments.

The advantages associated with using fibres in the pre cast segments are -

• Better mechanical strength
• Improved pre cast production time
• Improved damage resistance during transportation and placing
• Improved quality in aggressive environments
• Concrete thickness reduction as no reinforcement cover depth is required.