MaineDOT CADD Standards

MaineDOT has changed units for InRoads files to U.S. Survey Foot. In 2006, MaineDOT made a decision to migrate from MX to InRoads. In order for InRoads and MicroStation to work well together, we made several changes to our MicroStation configuration and standard seed files. The following are the major points:

Change in Units to US Survey Foot

• Due to decisions made many years ago, the survey and mapping community in the United States uses a slightly different definition of the length of a "foot" than does the rest of the world.
• 1 US Survey Foot = 1.000002 International Foot
• This is a difference of 2 ten-thousandths in 100 feet. It is generally not significant when measuring distances within our projects. However, the origin of our coordinate system is far enough away that you will have a significant error if you try to superimpose (reference) graphics drawn in one system over graphics drawn in the other.
• Our prior system was sort of a hybrid setup, where MX work was done in the US Survey Foot, but our MicroStation files were based on the International Foot.
• Due to the fact that InRoads does its work within the MicroStation graphics environment, we had to bring them into alignment. Therefore, on new projects, both InRoads and MicroStation are now being set up on the US Survey foot definition. This is defined in our custom units.def file which is located in our !msInRoadsconf\standards\data folder.

Change to Units of Resolution (UORs)

• When we first developed our MaineDOT MicroStation configuration, there were several limitations in the software that have been removed in more current versions. In our earlier system, we chose a resolution of 1524 units per International Foot. This provided a convenient ratio for switching between metric and imperial units, and represented the best compromise between the size of the Design Plane and the accuracy desired for survey computations, etc.
• Now, MicroStation no longer requires a trade-off between the size of the Design Plane and the level of accuracy. We now use a resolution of 1000 units per millimeter, which is the same as used by some other DOT's. While that resolution seems like more than we would ever need, it pretty much assures that MicroStation-induced rounding errors will no longer be a problem in survey and alignment calculations.

Updating old files to new UORs and Units

• The downside of the "improvements" in the Units and UORs is that we need to convert old files to the new setup, in order to use them together with new files.
• This conversion is tedious to do manually, and subject to user error. Therefore, we wrote a program (VBA macro) to do this conversion. After conversion of the older files, references will line up correctly. In MicroStation's main menu, under the InRoads pull-down, look for "Update UOR and units".

Expanded Level Structure and Naming

• New Level StructureBentley's "best practices" suggestion for InRoads configuration requires that names be coordinated for InRoads Features, Styles and Named Symbologies, as well as MicroStation Levels.
• Implementing the above recommendation requires that there be one named level corresponding to each named feature (For MX users, a feature name is approximately the same thing as a string label).
• MicroStation now supports a practically unlimited number of levels.
• We looked at naming conventions used by other D.O.T.'s, but decided to use similar naming convention used by the US military (our old-time GDS users will recognize this) which goes from the general to the specific.
• In the example here, the first "D" stands for "designed". An "S" stands for "surveyed", "M" stands for "mapping surveys", "P" stands for "proposed Right of Way", "E" stands for "existing Right of Way" etc. (download the example graphic)
• This convention seems much more readable and user-friendly than the coded naming convention used in some of the DOT's.
• Our new Level Naming convention and structure provides space for the earlier 63+ levels. Therefore, older MicroStation graphics may be combined with the newer graphics without conflict.

DGN Library Files

• Management of the new level structure is accomplished using a .dgnlib file. This is an empty library file that contains the level structure consistent with MaineDOT standards. This is important for the management of the level structure. When a change to the level structure is necessary, the MicroStation files will automatically synchronize themselves to the library file.

Border size for projects in U.S. Customary units 

• Our full-size plan sets are now 22” x 34”.  However, we are still printing on a 36” wide roll stock with a slightly oversized left margin. We are not trimming these plans in-house, so consultants are not required to do so.
• Our half-size plan sets are now 11” x 17”.  We are still printing them on 18” wide roll stock, with an oversized left margin.
• The border’s plot boundary shape measures 22” x 34” in full size and 11” x 17” in half size. 
• This change makes it possible to print half-size plans to scale on standard 11" x 17" paper.

Engineering Signatures & Seals

• For U. S. Customary projects, we are including an engineering signature and seal box on all sheets in a plan set.  However, we still use an Engineer's signature and seal only on the title sheet, unless a different Engineer is responsible for specific sheets within the plan set.

Standard Units	US Customary
Master Unit	' (Survey Feet)
Sub Unit	" (Survey Inch)
Su/Mu	12
Pos/Su	25,400.05
Resolution (Vi8 Advanced)	1,000 per millimeter

These units are MaineDOTs customized units. They are defined in the units.def file. Users that are not using our configuration will need to copy this file into their C:\ProgramData\Bentley\MicroStation V8i (SELECTseries)\WorkSpace\System\data folder in order to get the same results.

We expanded our Level structure drastically with the implementation of InRoads and broke them up in the five major categories. All Design Levels begin with a "D" and are for all design aspects of any given project. All Survey Levels begin with an "S" and are intended for all "ground" surveys. All Mapping Levels begin with a "M" and are intended for aerial mapping surveys. All Existing ROW Levels begin with an "E" and all Proposed ROW Levels begin with a "P."

We then break the name into parts, going from the general to the specific, separated by an underscore. Our Settings Manager's Category and Groups are intended to be similar to the remainder of the Level names providing a smooth and familiar workflow. Our new Level Naming convention and structure provides space for the earlier 63+ levels from all pre-existing level structures which combined span the first 99 levels. Therefore, older MicroStation graphics may be combined with the newer graphics without conflict. There are too many levels to list so instead we have exported them from MicroStation as .csv files.

• Design Levels (Excel)
• Survey Levels (Excel)
• Mapping Levels (Excel)
• EROW Levels (Excel)
• PROW Levels (Excel)
• Original Levels (Excel)

Management of the new level structure is accomplished using a .dgnlib file. This is an empty library file that contains the level structure consistent with MaineDOT standards. This is important for the management of the level structure.

When a change to the level structure is necessary, the all new MicroStation files will automatically synchronize themselves to the library file. The dgnlib files also have bi-level symbology built in to help with mapping of level, color, style and weight. We are not currently using bi-Level symbology, however it's there for future use and to aid the consultant community.

General Information

• The MaineDOT depends upon a project-oriented folder structure to identify which project each file belongs to. The filenames are identical from project to project. Therefore, it is very important to keep all project files in project folders! Many of our automated routines depend on files being named appropriately in accordance with our convention. Remember - The computer is not smart enough to find files that have been misnamed!
• We have a macro called MAKESHEETZ that facilitates making and naming drawing files to our standard. See our MicroStation/InRoads Manual for more information on this macro.

Sheet Files

• We do our plan-view editing on project-wide drawings and use "sheet" drawings with borders and referenced saved views to create the sheets for plotting.
• The names of these sheet drawing files are given a prefix of three numbers and an underscore. We have a utility program for organizing and renumbering sheets that renames these files accordingly. Examples of numbered sheet files are:
  • 001_Title.dgn
  • 002_Typical_01.dgn
  • 003_Typical_02.dgn
  • 004_Estimate.dgn
  • 005_Drainage.dgn
  • 006_Notes_general.dgn
  • 007_Notes_const.dgn
  • 011_HDPlan1.dgn

Notes Regarding Filename Variations

• If everyone follows the rules for file naming, it will be much easier to make both manual and automated procedures work properly. There are times when variations in standard file names will be required. Our procedures are designed to work with the following rules for filename variations.
  • DO NOT use a prefix, except for the three allowed cases, which are:
    • nnn_ for sheet files as described above
    • c_ for colored sheets that are not part of the official plan set
    • z_ for work files used in detailing
    • The z_ files are where the structural details are edited. They are typically referenced from numbered sheet files when plotting
  • DO use a suffix starting with an underscore when you make variations of standard file names. Examples of proper use of a suffix are:
    • alignments_a.dgn
    • alignments_b.dgn
    • highway_alt1.dgn
    • highway_alt2.dgn
  • Allowable suffixes include :
    • _det
    • _elev
    • _plan
    • _wing
    • _sect
    • _foot
    • _rehab
    • _alt#
    • _c
    • _prelim
    • _w
    • _exist
    • _final
    • _#

• MaineDOT Folder Structure and File Standards (PDF)

MaineDOT uses custom fonts for the majority of plan production, they are incorporated in our MicroStation and InRoads configuration files found on the MicroStation/InRoads configuration page. In addition to our resource files for MicroStation, we are have exported them as AutoCAD .shx files for the consultant community.

• AutoCad-shx files (ZIP)

We are also providing a table of our fonts at the various scales based on the standard drawings in any given plan set. Each font is sized appropriately in the table for the multiple scales (using Annotation Scale the font size is automatically set correctly).

• US_Font-table (PDF)

MaineDOT uses MDOTCOLORS.TBL. The colors in the first row were arranged to facilitate data translations from MX. The "whites" in the right two columns of rows 3 through 15 are available for users to define custom colors if they need something that is not already available.

You can also download MDOTcolors.pdf, which shows two versions of the above chart, one with the MicroStation Color Numbers and one with the RGB Values of each color.  This information may be useful if you are trying to match our color table in other software, such as AutoCAD.

Information about special interpretations of certain colors by MaineDOT's customized MicroStation Plot Driver files (PLT's) is documented in the file PlottingComments.doc.