A close look in the audit clarifies what's happening. There are up to 6 discrete envelopes evaluated for each section of the design strip (and for each design task). Each envelope is a complete set of section design forces (axial loads, shear forces and moments). See the program manual section "How RAM Concept calculates envelope results" for details.
When the capacity of the section is evaluated it is done for each envelope individually. There are situations in concrete design where the demand affects the capacity. For example, axial tension on a cross section can reduce the bending moment or shear capacity, but if the tension only occurs when the bending and shear forces are reduced, this may or may not control the design.
At the end of the audit, the program reports a Final Check with the Minimum and Maximum capacity and demand values from all evaluated envelopes in a single summary table. Since these demand and capacity values may not come from the same envelope this can appear like there is a problem when rally there is none.
Plotted results showing the Min. and Max. Demand and Capacity curves is also subject to the same thing.
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