Answer:
In the case of a ground failure analysis or soil contact stress analysis, the "equivalent surface" is determined in RF‑/FOUNDATION Pro in order to calculate the soil contact stress.
If the foundation dimension is smaller than twice the load eccentricity "e", the "equivalent surface" or the "effective foundation" cannot be determined. In this case, you receive the corresponding error message.
In most cases, the problem is that a user has entered dimensions of the foundation plate that are too small.
To remedy the problem, you can manually set greater dimensions. Or select the "Dimensioning" feature.
