My agency uses girder stops at abutments and expansion piers. These act as guides that allow the girders to move freely during expansion, contraction, and seismic events without falling off the bearings. Modeling these would allow for more accurate representation of the structure being modeled and will better aid in sheet production, reinforcing modeling, material quantities, and possibly even seismic analysis.

to model these, it could be an option in the pier or abutment creation window. if checked it provides additional parameters for things like:

1. parallel to deck, or level

   1. if parallel, provide the girder stop height

   2. if level, provide the MINIMUM height

2. the height as specified in steps a and B above are the height above the top of the abutment wall where the girders rest on

3. width

   1. this could either be the width of the girder stop between girders, or the width of the girder well (centered on beam centerline).

      1. using the beam centerline might be the easiest option to program in

4. depth

   1. in most cases these are the full thickness or depth of the wall, but some scenarios may require something different. this would allow design flexibility.

      1. one example is on an intermediate expansion pier you might have the girders for each span coming in at different angles (common for curved bridges with straight precast girders). rather than pour large, angled girder stops, each set of girders on that pier would have their own girder stops.

      2. another example is that on an expansion pier, it might be a case where the incoming span has 5 girders, and the outgoing span has 6 as the roadway starts to widen to accommodate an exit ramp or something. having the girder stops be the full depth of the wall would not allow for this sort of scenario

5. tying in with the above example, allowance of up to 2 girder stop layouts at each pier

the software would most likely model these elements as a single wall and then use the width parameter to cut the girder wells out between girder stops. Please see the attached screen clips and details. Girder stops are highlighted in blue