Create corridors with noncenterline baselines. Although for simple corridors you may think of a baseline as a road centerline, other elements of a road design can be used as a baseline. In the case of a cul-de-sac, the EOP, the top of curb, or any other appropriate feature can be converted to an alignment and profile and used as a baseline.
Master It Open the Mastering Advanced Corridors.dwg file, which you can download from www.sybex.com/go/masteringcivil3d2012. Add the cul-de-sac alignment and profile to the corridor as a baseline. Create a region under this baseline that applies the Typical Intersection assembly.
Add alignment and profile targets to a region for a cul-de-sac. Adding a baseline isn’t always enough. Some corridor models require the use of targets. In the case of a cul-de-sac, the lane elevations are often driven by the cul-de-sac centerline alignment and profile.
Master It Continue working in the Mastering Advanced Corridors.dwg file. Add the Second Road alignment and Second Road FG profile as targets to the cul-de-sac region. Adjust Assembly Application Frequency to 5′, and make sure the corridor samples are profile PVIs.
Use the Interactive Boundary tool to add a boundary to the corridor surface. Every good surface needs a boundary to prevent bad triangulation. Bad triangulation creates inaccurate and unsightly contours. Civil 3D provides several tools for creating corridor surface boundaries, including an Interactive Boundary tool.
Master It Continue working in the Mastering Advanced Corridors.dwg file. Create an interactive corridor surface boundary for the entire corridor model.