Weight Limit Signs

 

Not all bridges were designed to carry today’s maximum legal weight vehicles, and those that cannot safely support all legal vehicles must be weight restricted. Weight limit signs are intended to prevent vehicles with loads too heavy from crossing a bridge that has been classified as structurally weak. The signs also help extend bridge service life by preventing damage and potential failures.

 

 

The most common weight limit sign

	This is the most common type of bridge load posting sign. It uses typical configurations to represent commonly recognizable vehicles, as it is not reasonable for signs to show all vehicles. The number of axles shown on each silhouette is a simplified example only, and actual axle configuration may differ.
Single-Unit Truck	The single-Unit truck has a power unit and trailer that form one vehicle. The power unit and trailer are not designed to be detachable.
Tractor & Trailer	For this vehicle, the power unit or single unit truck is detachable from the trailer. The total number of axles is rarely less than four, and often as high as six or more.

Tractor & Two+ Trailers

This vehicle combination consists of three (or more) units that are detachable from one another. This includes any power unit with a minimum of two trailers.

 

 

Other common weight limit signs

	These signs are often used where severe load restrictions apply. The gross vehicle weight or axle weight for any vehicle class is limited regardless of how many axles the vehicle has, or their configuration.
	This type of sign is frequently used to combine the load posting information. The gross weight and/or axle weight of the vehicle cannot exceed the limit shown on the sign, no matter of how much of the vehicle is actually on the bridge at any one time.

 

Bridge weight restriction signs vary between States and localities. If you do not understand the signs in your area, contact the local or State transportation agency.

 

 

Vehicle types & classifications