Fiber-based projected concrete is used in applications that require a rugged solution with a simple execution
Projected concrete with the addition of short-length fibres is used as a support on tunnel surfaces. The application process consists of pressurizing concrete reinforced with steel fibres or structural polymer fibres onto the surface to produce a layer capable of withstanding different loads depending on the thickness, reference and dosage.
The most commonly used fibres are between 30 and 35 mm long with a diameter between 0.5 and 0.75 mm. The length of the fibre must be less than 2/3 of the inner diameter of the concrete-pumping tube and, if possible, twice the size of the major aggregate.