If you look at the post-processing > beam unity check table, you can find that there are three ratio mentioned as shown in the following figure--
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The actual ratio is the ratio of actual critical force by the section capacity. For limit state method, the capacity of the member is calculated for factored load case. For example, for IS800:2007 code, both material safety factor and load safety factor is considered to calculate the section capacity. So the calculated ratio depends on the factor of safety. This actual ratio is compared with the value provided under RATIO parameter, by default the value of which is 1. So if the actual ratio is greater than 1, then the member is declared as Fail. If you want to increase or decrease the ratio - use the RATIO parameter.
