Autodesk AUTOCAD PLANT 3D 2011 - SYSTEM REQUIREMENTS, Tutorials Manual

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For more information, see the AutoCAD Civil 3D Help topics Understanding Intersections and
Understanding Roundabouts.
Tutorial: Creating Intersections
This tutorial demonstrates how to create several types of intersections.
You will create two basic types of intersections, which differ in how the
intersecting road crowns are blended:
■ In a peer road intersection, the crowns of both roads are maintained. The
primary road centerline profile is maintained, and a locked PVI is created
on the secondary road centerline profile where it intersects with the primary
road centerline. The pavement of both roads is blended into the curb
returns.
■ In a primary road intersection, the primary road crown is maintained. The
primary road centerline profile is maintained, and a locked PVI is created
on the secondary road centerline profile where it intersects with the primary
road centerline. Two additional locked PVIs are created on the secondary
road centerline profile at the primary road edges of pavement. The primary
road cross-slope is maintained, and the secondary road pavement is blended
from the primary road edges of pavement along the secondary road
pavement edges.
You will also experiment with curb return widening parameters, which are
used to create turn lanes.
For information on adding widening regions to offset alignments that are
outside the intersection area, see the
Adding a Widening to an Offset
Alignment (page 239) exercise.
For more information, see the AutoCAD Civil 3D Help topic Creating
Intersections.
Exercise 1: Creating a Peer Road Intersection
In this exercise, you will create a three-way intersection and generate a corridor
that maintains the crowns of both roads.
To create a complete intersection model, you must have a centerline alignment
and profile for each of the intersecting roads. The horizontal and vertical
496 | Chapter 14 Intersection and Roundabout Tutorials