Planning for Commercial Vehicle Weight Limit Change: Application and Computer Software

Abstract

Commercial vehicle weight limits here refer to those on the gross weight, axle spacing, and axle weights. They have a notable influence on the deterioration and lifespan of highway facilities such as pavements and bridges. A new methodology is presented here for estimating the monetary impact to a network of highway bridges due to commercial vehicle weight limit increase. This methodology focuses on four categories of cost impact: (1) life reduction due to fatigue of steel components; (2) life reduction due to fatigue of reinforced concrete decks; (3) requirements for addressing deficiency of existing bridges; and (4) capacity requirements for new bridges. For illustration, an application example of the new methodology is presented. The results show that Categories 3 and 4, additional inadequate bridges and increased requirements for new bridges, contribute more significantly to the total impact cost. In addition, a computer software program for the methodology has been developed and is introduced in this paper to facilitate implementation. It is intended to be used for highway planning at different network levels, such as for state, provincial, federal, or national jurisdictions.