Why end hogging moments are generated for pin-pin supported girder?

To understand the reason for hogging moments at the ends of pin-pin supported girder, we need to first understand how the "Section Offset" works.

Detailed explanation of Section Offset is given in our online help manual

If vertical offset is provided (like Center-Top) then the program will create rigid links to join the offset point and the centroid of the section.

For example, when a pin-pin boundary condition is specified to the girder having section offset as Center Top, then the program will create the rigid links as shown below:

The Bending moments generated at the Neutral Axis will be displayed at the Reference line. By this approach we are considering the effect of section offset in the program.

For a rectangular section with offset 1) Center-Center  Vs   2) Center-Top, below moments will be generated.
PFA the comparison model file.

Creation date: 4/25/2019 12:24 PM      Updated: 9/8/2023 11:54 AM
1 Indeterminate beam offset check.mcb
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