Using anonymous probe-vehicle data for a performance indicator of bridge service

Abstract

Anonymous probe-vehicle data are being used to evaluate travel time reliability and congestion conditions along roadways. These telematics data are collected from commercial and private cell phones, global positioning system devices and on-board vehicles computers. In the last few years, these data have been incorporated into reports of highway and arterial systems to measure congestion conditions. For this paper, anonymous probe-vehicle data were used to calculate a congestion metric, at bridge locations in New Jersey, USA, based on aggregated yearly congestion hours. The congestion metric was then compared to the functionally obsolete (FO) performance designation defined by the US National Bridge Inventory (NBI). These FO bridges represent structures that, according to the NBI, theoretically cause congestion. The comparison showed that the FO designation did not indicate high levels of congestion and vice versa. Consequently, when the congestion metric was implemented in a rudimentary management strategy, it provided a clearer decision-making process over the current traffic carrying metric in the NBI. The results of this study show that the aggregated congestion metric can serve as a useful performance indicator for bridge structures at a regional level, and it can provide value when incorporated into a bridge asset management programme.