About the Controlling Criteria

The following information supplements PDDM Section 9.1.3:

The following chart summarizes the ten FHWA controlling criteria with typical sources for the specific values. Actual values depend on...

Highway Design Forms

The following forms apply to all FLH Division offices:

• Highway Design Standards - for documenting FHWA controlling criteria decisions and...

Highway Design Standards

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.

Beartooth Hwy - 3D Modeling

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...

Big Lake - 3D Modeling

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...

Cuba La Cueva - 3D Model

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...

Cuba La Cueva - 3D Modeling

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...

Guanella Pass - 3D Modeling

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...

Emerging Technical Innovations

Schedule Driven 4D Models

There are a few products available that allow the linking of a 3D CAD model to a schedule (Primavera or Microsoft Scheduler). These applications are commonly referred to as 4D tools. The tools are being applied more often to architectural and...

Analytical Simulations

There are a number of analytical simulation tools used for testing roadway designs. The tools can be used to test capacity for a system, intersection and signal timing performance, or general traffic flow performance evaluation for a road network. Some of the more common tools are: HCS, CORSIM,...