Simplified method


Longitudinal reinforcement is designed with the Simplified method from the French national application guide FD P18-717 of the norm EN1992-1-1. The simplified method should be applied if the following conditions are satisfied:



The formulas that should be used for calculation:



NRd = kh × ks × α × [b × h × fcd × As × fyd]


Rectangular section




Circular section






For the calculation of d':

calculation of d


Because, in the design phase, the real d' is not known, the software will use in calculation the concrete cover from the Concrete covers dialog:

d' = 25 mm


Design Assumptions  Concrete cover

Design Assumptions – Concrete cover




In the first stage, the calculation will be done using the value from the dialog and will result in a longitudinal reinforcement area and a transversal reinforcement area with certain diameters.

In the final stage, the calculation is done again with the real d' obtained as:


calculation d


The report will contain the final stage calculation, with the real value of d'.


Note: If the values of δ and ρ are not known, it can be considered that (1 - 6 × ρ × δ) = 0.95. The Advance Design module considers a value for kh=0.93.

With the Simplified method, the calculation is done on both planes, but the report keeps the results for the plan giving the maximum reinforcement area.