01504442

Component

http://onlinepubs.trb.org...es/2011/RSS/2/Moreno,A.pdf

Urban road safety management is usually characterized by both a lack of quantity and quality of crash data and low budgets. However, fifty three percent of road crashes in Spain take place on crosstown roads and urban areas. Moreover, ten percent of fatal crashes on urban areas occur on crosstown roads. In order to reduce both crash frequency and severity, traffic calming measures (TCMs) are often implemented on crosstown roads. The objective of the research is to develop a methodology using continuous speed profile on free-flow conditions to evaluate safety effectiveness of traffic calming measures on crosstown roads. Given the strong relationship between speed and crash experience, safety performance can be related to speed. Consequently, speed can be used indirectly as a surrogate safety measure. Two indexes were defined as surrogate safety measures based on the continuous speed profile: Ra and Ea, related to speed uniformity and speeding, respectively. The indexes were applied to both individual observed speed profiles and aggregated operating speed profile. Twenty four global values of both indexes were obtained. The scenarios with implemented TCMs according to technical criteria, such as a traffic calming density close to nine TCMs per km, presented lower values. Age and gender differences have also been evaluated. More scenarios based on speed predictions over the TCMs will be modeled to propose Ra and Ea safety threshold values. The paper explores continuous speed profiles obtained from naturalistic driving to assess safety performance of crosstown roads with traffic calming devices. With this approach, speed is in effect used as a surrogate safety measure formulated in two new indexes: Ra and Ea.

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01501394

English

21p

2011

3rd International Conference on Road Safety and Simulation

Digital/other

Figures; References; Tables

Crash data; Implementation; Traffic calming; Traffic safety; Traffic speed; Urban areas

Surrogate safety measures

Spain

Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control; I85: Safety Devices used in Transport Infrastructure

TRIS, TRB, ATRI

Jan 16 2014 4:27PM