I obtain different results when comparing the deformation analysis in the RF‑CONCRETE add-on modules and another calculation program. What could be the reason for this?


The differences resulting from the determination of the deformation in the cracked state can have various causes. In the case of deviations, you should check the following points:

Is the same calculation method applied?
RF-CONCRETE Deflect uses the analytical analysis approach according to EN 1992‑1‑1, 7.4.3.
RF-CONCRETE NL uses the physically nonlinear analysis approach.
You can find more information about the calculation methods in Chapter 2.7 and Chapter 2.8 of the RF‑CONCRETE Surfaces manual.

Is the same initial structure available?
If considering the underlying structural system as equivalent, the results of the linear calculation can be considered in the best way. The linearly determined deformation of the underlying combination should be approximately equal. Possible differences in the linear deformation may be increased in the cracked state in connection with the deformation analysis.

Are the same effects taken into account?
When comparing, make sure that the same effects, such as creeping and shrinkage, are taken into account (Figure 02). 

Are the same initial values available?
In connection with the deformation analysis, you should further check if the same initial values are available. In this case, a special attention has to be paid to the fact whether the applied reinforcement (Figure 03) and the lever arm or the concrete cover are the same.

If you cannot find the cause after the fundamental examination, please contact our hotline.


Comparison Program comparison Deformation analysis State II Nonlinear Differences Cause Frilo RIB D.I.E.


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