Answer:
Fire resistance design is not implemented in the RF‑LAMINATE add-on module by default.
However, you can calculate the charring rates yourself and consider them accordingly in the module. In the following example, this is explained on a simple plate.
Structural system (Image 01):
- Span 5 m
- Plate width 2 m
- LC1 (permanent) 1 kN/m² plus dead load
- LC2 (medium) 2.5 kN/m²
- 3 layers
- S1 35 mm C24
- S2 20 mm C24
- S3 35 mm C24
The information regarding the correction factors and stiffnesses can be found in the attached file.
Factors for fire resistance:
- Charring rate ß0 = 0.65 mm/min
- Pyrolysis zone k0d0 = 7 mm
- Charring time t = 30 min
- Effective thickness def = t ß0 + k0d0 = 30 min x 0.65 mm/min + 7 mm = 26.5 mm
Remaining thickness of Layer 3 = 35 − 26.5 = 8.5 mm > 3 mm → thickness may be applied (Image 02).
Because of the modified layer thicknesses, a new stiffness matrix results, which is applied in RFEM for accidental combinations with the characteristic stiffness values. For the ultimate limit state, the design values are calculated here (Image 03).
