Retrofit Railings for Through Truss Bridges

Through-truss bridges that have remained in service are required to handle traffic having characteristics that are greatly different from those that existed when they were constructed. Today's traffic is composed of heavier vehicles which travel faster and have different operating characteristics, making it desirable to have wide lanes, longer curves, and more sight distance. Some older through-truss bridges may have adequate load-carrying capacity, but are considered functionally obsolete because they are too narrow or have inadequate railings. Retrofit bridge rails can make it possible to leave many of these bridges in service until their replacement is economically feasible.