InTrans / Aug 14, 2018

The Development of Economical Low-Volume Road Bridges

Low-volume bridges are currently designed according to the same specification as urban highway bridges. Thus, many of the low-volume bridge designs are overly conservative and uneconomical. This report addresses the issue and proposes modifications of the existing specifications in the areas of fatigue, deflection, allowable stress, composite action of timber decks, bridge width, lane loading and the use of guardrails.
This study also proposes a method of selecting the type of bridge system to be built in a particular area and a priority scheme to select which bridges must be replaced first. The scheme models the FHWA sufficiency ranking with some of the ranking criteria being changed to better meet the needs of low-volume bridges.