In OBM, a limitation of the Wingwall component is that it has to be linear and cannot follow a horizontal curve.

By using the new feature to place barriers under the deck, it is possible to simulate the layout of wingwalls along a horizontal curve, provided the deck also follows a similar path.

 

The first step is to add a Wingwall template in the barrier library. Pay special attention to the constraints and use the appropriate "Elevation Provider Bottom" constraint option if the top of the wall is to accurately follow the bottom slope of the deck/approach slab. Notice also that the Working Point is defined at the top of the wingwall, and this becomes the attachment point between the top of the wall and the bottom of the deck. Similarly the wall height is a defined as a variable that can be defined by the user at placement time as a variable height. 

Next place the barrier on the deck or approach slab while ensuring that the Placement Surface is set to Bottom of the deck. Also specify variable constraints for the height of the wall so the bottom elevation is controlled. 

Note: The workaround suggested here is valid for version 2023 and beyond.