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The PDDM was first published in 1988 in English units. It was re-released in 1996 as a Metric document. Beginning in 2005 the document was published with dual units. The following archived versions of the PDDM are available for reference purposes ONLY within Federal Lands Highway offices (see...
The FLH Technical Guidance Manuals supplement the information provided in the PDDM. The following manuals are provided:
The following chart summarizes the ten FHWA controlling criteria with typical sources for the specific values. Actual values depend on...
The following forms apply to all FLH Division offices:
Rev: 31-Mar-2021
This form applies to all FLH Divisions. See more information about design exceptions and filling out this form.
Note: This form is not viewable within a web browser. Download the document for viewing and use.
The Beartooth Highway Road Improvement: Design Visualization Interactive CD-ROM is a good example of an effective interactive CD-ROM that utilizes logical information and interface design to weave a variety of different media into a coherent whole. Macromedia Director was used to author this...
The Big Lake photosims were a unique project in that even the background photo had to be created. The photo that was taken on site did not adequately show the two alternatives being considered. That photo was used as digital image source material to paint in a new background view over a 3D...
This case study will show some simple visualization techniques that can be accomplished entirely with Microstation and a few plugins and images for texture maps. The model is based on a road design file for a remote valley in New Mexico. One of the other case studies shows photosims produced for...
The Cuba La Cueva project was a pair of photosims showing a re-alignment and a proposed bridge in a scenic valley in New Mexico. This is a classic photosimulation example. A 3D model of the road design and bridge were produced in Microstation, as well as the surrounding context as a 3D DTM. A...
The Guanella Pass Proposed Road Improvements Project CD-ROM is an early example of a multimedia CD-ROM created to present a visual comparison between an existing highway and prosposed alternatives. Created for Windows 95, this project was developed before many of the newer technologies discussed...