Standard Drawings

The Bridge Program has developed standard drawings that require very little modification to be incorporated into a set of contract documents. These sheets should be used in contract documents when specified by the Principal Bridge Engineer.

Wyoming Tube Type Bridge Railing

Wyoming has crash tested two types of TUBE-TYPE bridge railing. The most commonly used railing meets the crash test requirements of NCHRP Test Level 3 (TL-3). This railing uses two TS 6 x 2 x 0.250 for the longitudinal rail sections.

The second rail type is designated as TL-4. It meets the crash test requirements of NCHRP Test Level 4. This railing uses a TS 6 x 4x 0.250 and a TS 6 x 3x 0.250 as the longitudinal rail sections. The TL-4 also incorporates a thicker plate for the post than the TL-3 rail. Additional reinforcing is required in the deck adjacent to the post anchorage, as well.
The links contain details and specifications of our railing, along with FHWA technical reports for both railing types.

Wyoming Traffic Signal Poles

The Wyoming Department of Transportation utilizes two standard traffic signal pole designs. These designs are based on four load cases which depict the maximum loading and the associated pole and signal arm properties.

Signal arms vary in length from 10 to 55 feet and may be either curved or straight.
The design conforms to the 2009 AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals, 5th Edition.
Design wind pressures are based on a 90 mph fastest-mile wind speed with a 1.3 gust coefficient in accordance with Appendix C. Fatigue Importance Category II is used for fatigue design. Fatigue design loads are the natural wind gust pressure range based on a yearly mean wind velocity of 12.9 mph, and truck-induced gust pressure range based on a truck speed of 55 mph.