By assigning different Part numbers to isolated cross-sectional elements at the Cross-Sections in RM Bridge Modeler users will create also isolated beam elements and nodes in the RM Bridge Analyzer section. This is very useful to have only one reference for the substructure but have multiple elements, as shown in the image below. Note that the Vertical Axis can be any other point because RM Bridge uses the Construction Lines 1 and CL2 intersection to be assigned to the alignment or axis.
It is also useful to create more than one girder for a grillage analysis. Note that in the case of Composite structures, like in the picture above, before the creation of the deck portions, Parts 2, 5, 8, and 11, the girders will be isolated and behave as individual disconnected beams. This is very accurate, especially when users include in the stage analysis the decks as initially just wet concrete being poured over the girders. Later, when Part2 is activated, then the Composite Part3 is considered as the "sum" of Part1 and Part2. Note that in this case, the Longitudinal Axis can be any other point because RM Bridge uses the Construction Lines 1 and CL2 intersection to be assigned to the Alignment.