The talented Jeff Bartels has come up with a technique to model InfraWorks 360 intersections that support dedicated turn lanes, and he shared this video with us to demonstrate the workflow. If you'd like to experiment with the technique, you can download the dataset Jeff used, and a template, here:Download Dataset
The latest of release of InfraWorks 360 supports offset intersections, so with the use of both right and left turn lane styles and an intersection object, Jeff created an intersection with multiple turn lanes, for visualization purposes. With additional tweaking of styles and alignments, other intersection configurations can be achieved too!
(This approach is intended for visualization purposes only for now, as it takes some liberties with design road alignments.)