I-5 Antlers Bridge Replacement

The California Department of Transportation (Caltrans), in cooperation with the Federal Highway Administration, proposes to replace Antlers Bridge on Interstate 5 in Shasta County over the Sacramento River arm of Shasta Lake near the community of Lakehead. The bridge is at or near the end of its service life. In addition, a 0.4 mile section of highway south of the bridge will be realigned due to a high accident rate. Traffic will remain on the existing bridge during construction of a new bridge on a parallel alignment. New right of way will be required.

Antlers Bridge Project - Month of May 2013

Periodic day time closures are expected this month in the NB direction to allow for concrete trucks to safely exit and enter the highway. Utility and work trucks/pickups will also continue to enter and exit the northbound lanes on the south end of the project. Please be aware and reduce speeds when traveling through the project limits. Images of the progress can be viewed at the following URL/
http://www.dot.ca.gov/dist2/projects/antlers/constructioncam.htm

Area Traffic Cameras and News Releases

NEWS RELEASES Antler Bridge Replacement Project Ground Breaking Celebration for Antlers Bridge Project

Form Traveler System

The Antlers Bridge superstructure, or bridge deck, will be constructed using a form traveler system similar to the one used on the Benicia-Martinez Bridge pictured here.

Both structures are segmental CIP (cast in place) balanced cantilever bridges. A cantilever is a long structure that is anchored on only one end. The cantilevers project out from opposite supporting piers and are then joined in the middle. The structures are balanced by building the segments on alternating sides. As its name implies, a segmental bridge is a bridge built in short sections, i.e., one piece at a time, as opposed to traditional methods that build a bridge in very large sections. Cast-in-place means the bridge is made of concrete and is constructed fully in its final location. This type of bridge is very economical for long spans (over 100 meters or 328 feet), especially when access to the construction site is restricted. They are also chosen for their aesthetic appeal.

The form traveler is a scaffold/formwork system that moves on rails and holds the rebar and fresh concrete as each section of the superstructure is constructed. After the concrete is cured, the completed section will support the form traveler as it is used to construct the next segment.