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

Creation date: 4/25/2019 12:24 PM Updated: 9/8/2023 11:54 AM section offset

Answer:

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

Link: http://manual.midasuser.com/EN_Common/Civil/881/Start/04_Model/05_Properties/Section.htm

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.

1 Indeterminate beam offset check.mcb

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

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