Autodesk CIVIL3D - CIVILDESIGNCOMP 2007 SLM CD Tutorials Manual page 81

5 Click Home tab
The drawing window zooms to the extents of the surface. With the
breakline data added, the layer that contained the source data for the
breaklines can be frozen.
6 Click Home tab
EG_BREAKLINES layer, click
Further exploration: Notice that, along some portions of the polylines, the
surface triangulation incorrectly crosses the breakline. This happened because
the surface contours also act as breaklines. The new breaklines are not added
because the contours are already acting as breaklines, and the current surface
setting does not allow more than one breakline to affect the surface at a given
point. To override this behavior, you can perform any of the following tasks:
Build the surface with contours and breaklines: In the Surface Properties
dialog box, on the Definition tab, expand the Build collection. Set Allow
Crossing Breaklines to Yes, and then set Elevation to Use to Use Last
Breakline Elevation at Intersection.
View panel views drop-down
Layers panel Layer drop-down. Next to the
.
Exercise 3: Adding Breaklines to a Surface | 69
Extents.