MX Final Design Summary v8i

The MX design process is an iterative procedure.  Because of this, we rely on input files to provide a record copy of the issued commands.  Input files can also be modified and rerun for design adjustments or creating design alternatives.  Refer to MX Input Files for more detail on working with input files.

MX project data is stored in various models grouped by type or purpose.  Refer to Model Names for MX for NHDOT model naming conventions.

An overview of the MX final design process follows:

A. Alignments

1. Input the Preliminary Design HALGN input files for all approved alignments.  Create both master alignments (MCxx) and their corresponding geometry strings (GCxx).  Modify these files to store alignments to a new model named FALIGN.
2. Use MX Alignment or MX Quick Alignment to create the horizontal geometry for all other master alignments (MCxx) and their corresponding geometry strings (GCxx).  Store these strings in the new FALIGN model.
3. Create HALGN input files from all alignments for future iterations.  HALGN input files are convenient to adjust model names, string names, and to set even station values.
4. Add additional points to master alignments for driveways, critical sections, and superelevations (or use major option EDIT).

B. Existing Ground Profiles

1. Generate Old Ground Strings (OCxx) for every master alignment in the model named FALIGN.
2. Attach Existing Elevations to all master alignments.

C. Existing Ground Sections

Use the Cross Section Viewer to cut existing ground (E) cross sections (or use major option SECTION).  Refer to MX Cross Sections for details on cutting sections.  Store these cross sections in new model/s named FSECTMCxx.

D. Proposed Profiles

1. Generate a Report of the existing profile to determine vertical match elevations and grades.
2. Reference the Preliminary Hearing Profile, compile a Verat input file to apply the proposed vertical geometry to the master alignment strings in the FALIGN model.  Adjust proposed grades at the project matches to tie in to the existing alignment.  Adjust proposed profiles up 1.5" (40mm) for Overlay Pavement Match projects.  VERAT input files are convenient to adjust curve lengths and to set even station values.
3. Copy each elevated master string (MCxx), its corresponding old ground (OCxx) and geometry (GCxx) strings to new model/s named FDESIGNMCxx.
4. Refer to Transferring MX profiles to MicroStation for details on drawing and transferring profiles.

E. Proposed Design Strings

1. Use Road Design options to generate the proposed roadway strings (or use major option DESIGN).  Store these strings in the FDESIGNMCxx model.
2. Use the Cross Slope Checker to report existing superelevations.
3. Use Road Design options to apply Rule-based Superelevation... to the proposed roadway strings.  Adjust the superelevations at the project matches to tie in to the existing pavement.
4. Use the MX Earthworks Wizard for proposed slopes (or use major option INTERFACe).  Store these strings in the FDESIGNMCxx model.

F. Proposed Cross Sections

1. Use the Cross Section Viewer to re-cut existing cross sections (or use major option SECTION).  Use the Cross Section Viewer to cut design (D) cross sections  Refer to MX Cross Sections for details cutting sections.  Refer to Cross Section Set Labels for description of section set labels.  Store these cross sections in new model/s named FSECTMCxx.
2. Generate the detail cross sections, refer to Adding Details to Cross Sections for the process.  Refer to Cross Section Set Labels for description of section set labels.  Store these cross sections in the FSECTMCxx model.
3. Create a drawing input file using the XS-MS Drawing Macro.

G. Iteration

It is extremely important that users understand implications resulting from modifications to the master string (horizontal or vertical shifts, addition or deletion of points).  This REQUIRES REITERATION OF ALL STEPS which are dependent upon the modified string!  Maintaining accurate input files is integral to inevitable design modifications.