EN 14488-5:2006

Overview

EN 14488-5:2006 is the CEN standard that specifies a laboratory method to determine the energy absorption capacity of fibre‑reinforced sprayed concrete (shotcrete) slab specimens. The standard defines how to obtain the load‑deflection response of a centrally loaded slab and how to calculate the absorbed energy up to a specified deflection. It is part of the EN 14488 series on testing sprayed concrete and was approved by CEN in 2006.

Key Topics and Requirements

• Test principle: A fibre‑reinforced slab specimen is centrally loaded under deflection control; the load‑deflection curve is recorded and converted into an energy‑vs‑deflection curve.
• Specimen sampling and curing: Specimens are produced and cured in accordance with EN 14488‑1 and EN 12390‑2 (making and curing specimens).
• Apparatus and control:
  • Testing machine capable of displacement control with a load‑system stiffness of at least 200 kN/mm.
  • Electronic transducer for central deflection with resolution ≥ 0.02 mm and continuous data logging.
  • Rigid square support frame (internal dimension ~500 mm) and loading block (contact surface ~100 mm × 100 mm) with suitable bedding material (mortar/plaster).
• Loading procedure:
  • Displacement‑controlled loading at a constant rate of (1 ± 0.1) mm/min at the slab centre.
  • Test continued until central deflection reaches ≥ 30 mm; load and deflection recorded continuously.
• Results and reporting:
  • Energy absorption capacity (in joules) is reported as the area under the load‑deflection curve between 0 and 25 mm deflection.
  • Test report must include specimen identification, slab dimensions and thickness, crack pattern, machine type and stiffness, load‑deflection curve, maximum load, energy‑deflection diagram, energy value (nearest 10 J), deviations, and declaration of conformity.
• References: Normative references include EN 12390‑2 and EN 12390‑4; EN 14488 series Parts 1–7 are related.

Applications

• Quality control and acceptance testing of sprayed concrete/shotcrete in tunnelling, underground works, civil repair and reinforcement applications.
• Comparative evaluation of fibre types and dosages to assess post‑crack toughness and energy absorption performance.
• R&D and material development for fibre‑reinforced concrete mixes where load‑deflection behavior and toughness are critical.
• Structural verification where residual capacity and ductility of sprayed concrete layers are required.

Who should use this standard

• Construction and geotechnical laboratories performing shotcrete testing.
• Contractors and specifiers responsible for sprayed concrete quality assurance.
• Material scientists and research organizations evaluating fibre‑reinforced shotcrete mixes.
• Authorities and consultants setting performance specifications for tunnel lining and repair works.

Related Standards

• EN 14488‑1 (Sampling fresh and hardened sprayed concrete)
• EN 14488 (other parts covering compressive strength, flexural strength, bond strength, thickness, fibre content)
• EN 12390‑2, EN 12390‑4

Keywords: EN 14488-5:2006, sprayed concrete testing, fibre reinforced slab, energy absorption capacity, load‑deflection, displacement‑controlled testing, shotcrete quality control.