Author: James L. Powell

Date of Publication:  1999 (?)

Sponsoring Agency:  U.S. Transportation Research Board, Committee on Railroad-Highway Grade Crossings

Abstract:

Basic research into effects of rail-highway grade crossings on highway users was conducted. The overall objective was to investigate improved techniques for estimating nonaccident effects, such as excess delay, user costs, direct energy consumption, and pollutant emissions. Numerical results also were desired. A microsimulation model is developed for analyzing delays due to train blockages at grade crossings not affected by other highway system bottlenecks. An analytic model is then developed to estimate effects of a vehicle slowing at grade crossings with no train present due to rough surface conditions. These models are validated to the extent possible based on field studies. A sensitivity analysis reveals that for most practical applications, train blockages can be analyzed more easily by using simple equations. A sample application of the method is presented in which 385 grade crossings are evaluated from which design options have been selected. The model developed for analyzing effects of a vehicle slowing with no train present is recommended for further applications, although more extensive validation studies are desirable. Numerical results indicate that nonaccident costs of grade crossings dominate accident costs in the ratio of about 3.5:1. The effects of a vehicle slowing with no train present dominate effects of train blockages in the ratio of about 2:1. The methods developed are felt to represent a significant improvement over earlier techniques for estimating highway-user effects. The methods can be applied to evaluation of alternatives such as rail relocations, construction of grade-separation structures, and crossing-surface improvements. Areas of further research are also identified.
 

No. of Pages:  8