Tutorials CivilCraft help Walkthroughs
Sweep a road corridor
Turn on a corridor for an alignment, set lane, shoulder and side slope values, and read the sections, daylight lines and earthwork it produces.
Written for CivilCraft 0.3. The same help is inside the app: press F1.
A corridor sweeps one simple typical section (an assembly) along an alignment and its design profile, grades it into the existing ground and adds the result to the proposed surface. In this build each alignment can carry one corridor, and the assembly is the same on both sides.
The assembly
From the centerline outward, on each side:
- a lane of a given width, falling away from the crown at the lane slope
- a shoulder of a given width at the shoulder slope
- a side slope from the shoulder edge to where it meets the ground: the cut slope where the ground is above, the fill slope where it is below
The starting values are placeholders, not a design standard:
| Value | US feet | Metres |
|---|---|---|
| Lane width | 12 ft | 3.6 m |
| Lane slope | 2% | 2% |
| Shoulder width | 4 ft | 1.2 m |
| Shoulder slope | 4% | 4% |
| Cut slope | 2 : 1 | 2 : 1 |
| Fill slope | 3 : 1 | 3 : 1 |
| Section every | 10 ft | 5 m |
Slopes for side slopes are horizontal to vertical (H:V): 3 : 1 means 3 across for 1 down.
Build the corridor
You need an alignment without errors and a design profile with at least two PVIs and no errors.
- Select the alignment.
- In the right panel, under Corridor, tick Sweep an assembly along the design profile. The fields appear and the corridor is built at once. The plan shows the edges of lane and shoulder and the daylight lines; with Proposed (graded) chosen under Display, the contours show the new ground.
- Change any value: Lane width, Lane slope, Shoulder width, Shoulder slope, Cut slope, Fill slope, Section every. Press ReturnEnter after each. Cut, fill and section spacing must be more than 0.
- Read the line under the fields, for example "39 sections from 0+00.00 to 3+86.36; cut 240.2 cu yd, fill 556.0 cu yd."
Sections are cut at every Section every step, at the ends, and at the start and end of every horizontal and vertical curve. Each section and the lines through them (centerline, edges of lane and shoulder, daylight) become breaklines of the proposed surface.
To turn the corridor off, untick the box. Its values are kept for next time.
When it does not build
A red box under the fields says why:
| Message | What to do |
|---|---|
| "The corridor needs a design profile without errors." | Add PVIs, or fix overlapping vertical curves (see Design a vertical profile). |
| "The design profile does not overlap the alignment." | Move the PVIs onto the alignment's station range. |
| "The corridor needs at least two sections on the surface." | Most of the corridor is off the existing ground. |
| "4 side slopes run off the surface before meeting the ground." | Near the edge of the surface the slope cannot reach the ground. Keep the road away from the edge, or lower the fill or cut height there. |
| "The corridor’s daylight lines cross (sections overlap, for example on the inside of a tight curve). Use a larger radius or narrower assembly." | Sections on the inside of a sharp curve overlap. Increase the radius or narrow the assembly. |
A corridor with a problem is not graded in and does not count in the earthwork.
Corridors and pads together
The proposed surface is built in order: every corridor first, then every pad. Where a pad's grading overlaps a corridor, the pad wins. Volumes are worked out inside all the daylight lines together; see Earthwork volumes.
What is not built yet
Curb and gutter, sidewalks, superelevation, widening, different assemblies on each side or along the road, regions and targets are not available yet. See Not built yet.