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Answer: Please note that the deck and the girders are connected to common joints to model a composite action. The jumps in the moment diagram at these connection points are caused by forces that are being applied by the deck to the girders at these connections. You can reduce these jumps if you refine the discretization Discretization DRAFT for the shell or frame elements to make these connection points distributed closely to each other.
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- You could create a sequence of section cuts to obtain the design forces - see Section cut FAQ page, item "Can the program display force diagrams based on a sequence of section cuts?" for additional details. This may require significant effort if done manually, but it would be a reasonable approach if it is automated using Application Programming Interface (API). The discretization should be refined as needed in order to adequately define the section cuts.
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