When building a Road model it produces 3D geometry (solid, surface, line) to Quadri. It is these geometries that we push out to the quantity report that is available from the task.
It is possible to use the Table Summary in Quadri to get out most of this information, and there you can also summarize across multiple road models.
Below is an overview over the geometries that gets into each of the quantities in the report. Click to expand in a new window.