1293x
002683
2019-03-26

Question

Why is the deflection of a reinforced concrete beam in RFEM / RSTAB in State 1 different from my manual calculation?


Answer:
It can often be the case that selecting outdated materials has an impact on the beam deformation. Please note that the material properties should always be taken from the respective standard. The material properties of the same material may differ, depending on the standard and its National Annex.

The same concrete was selected in this example, but the C35/45 | DIN 1045‑1 concrete has a lower modulus of elasticity compared to the C35/45 | DIN EN 1992‑1‑1 concrete (see Image 01). Consequently, a larger deflection is created in the mid-span of the reinforced concrete beam, which is only loaded by its self-weight (see Image 02).