This tutorial demonstrates how to use feature lines to control grading around inside corners.
Feature line grading involves creating a set of feature lines to define the graded region as surface breaklines, and then adjusting the elevation of key points to control the shape of the surface. This technique is ideal for wide, fairly flat areas, such as parking lots or building pads. It is also well suited to areas with rapidly changing elevations or slopes where walls would normally be required to grade successfully. You can manually add or remove feature lines and adjust their location in three dimensions to achieve precise slope design. Using this process, you can control water drainage or clean up difficult geometry in areas, such as the intersection of two or more slopes.