The Support Capacity Graph values are for each individual reinforcement member. These values can be easily exported to Excel from RS2.
Reinforcement Support Capacity Graphs
If you Graph Liner Data, the values are per meter and represent the values in the beam elements used in the analysis.
The method used to determine the forces and moments in each individual member is described in the following reference:
Carranza-Torres, C., Diederichs, M. (2009) Mechanical analysis of circular liners with particular reference to composite supports. For example, liners consisting of shotcrete and steel sets. Tunnelling and Underground Space Technology. 24(5):506-532
Evert Hoek’s Kersten lecture also deals with the spacing of steel sets.