Abstract

Travel time reliability is defined as the degree of certainty and predictability of travel time on a transportation system. Reliable transportation systems provide some guarantees to reach a particular destination within a reasonable time in harmony with the expected time. In this study data collection process on the specified paths was carried out through the test vehicle equipped with GPS (moving vehicle technology) device. The Statistical Package program(SPSS) was used to analyse the total travel time of each link on the three selected routes and the estimated speeds based on GPS field data collected during 50 running trials in the south and north directions during morning and evening hours. The results of buffer time indexes for three routes are presented for each route from Bayaa to Bab Almuadam to illustrate changing structure of the reliability during the peak period. Extra delays with regard to free flow travel time are observed on route 1, 2, and 3 in terms of 95% percentile travel time about 52, 38, and 41%, respectively.

References

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