Methodology to Estimate the Distance Traveled by Trucks on Rural Highway Systems

Abstract

Truck travel, normally expressed in terms of truck vehicle-distance travel (VDT), is a critical data requirement for the design, construction, operation, and management of rural highway systems. The need to estimate and characterize truck travel on a system-wide basis, yet retain a compatible, site-specific mining capability, challenges the traditional approach of traffic monitoring programs. This paper develops and applies a two-phase methodology to estimate truck VDT on rural highway systems. The first phase, which leverages the approach recommended for developing truck traffic data inputs for mechanistic-empirical pavement design, processes vehicle classification data obtained from continuous, sample, and manual counts into annual average daily truck traffic (AADTT) estimates by vehicle class. The second phase attributes these site-specific AADTT estimates to highway segments comprising a rural highway network. The methodology, which is transferrable across jurisdictions, integrates standard statistical procedures with engineering judgment and trucking industry intelligence by establishing transparent decision algorithms and criteria. Application of the methodology using real data reveals relevant limitations and illustrative results that have application to a wide range of transportation engineering decisions.