In schedule action “UltSup” with Reinforcement design selected, program calculates the necessary reinforcement area amount, required for the ultimate check capacity of the cross-section.

Presuming a plane strain over the cross-section, and a nonlinear stress-strain diagram of materials for the ultimate state, the stress distribution in the cross section is calculated.

The internal forces are obtained by integrating the concrete stresses and the stresses in the reinforcement steel and prestressed steel. Any reinforcement in the compression zone is considered, too.

The bearing capacity or capacity limit state is calculated by incrementing the individual components of the ultimate limit state, until the ultimate strain is reached, either in the extreme fibre of the concrete in compression zone or – as in most cases – in the critical reinforcement bar.

The individual components are in RM Bridge separately increased, hence yielding the limit state of the normal force capacity and ultimate moment capacities for the lateral moment My and the main bending moment Mz. The latter is often simply called the ultimate moment capacity. Presented below the diagrams considered for a Prestressed concrete section:

For the output of this action, User can have access to results presented in a *.lst file and perform the plot diagram, with the total area value obtained, throughout RM Sets.

By Attribute Sets definition and recalculating the reinforcement layout, User can either display the distribution of the total reinforcement area value, in the cross-section: