Engineering Solutions to Enhance Traffic Safety Performance on Two-Lane Highways

Lina Wu,Jiangwei Chu,Yusheng Ci,Xingwang Liu,Shumin Feng

doi:10.1155/2015/762379

Abstract

Improving two-lane highway traffic safety conditions is of practical importance to the traffic system, which has attracted significant research attention within the last decade. Many cost-effective and proactive solutions such as low-cost treatments and roadway safety monitoring programs have been developed to enhance traffic safety performance under prevailing conditions. This study presents research perspectives achieved from the Highway Safety Enhancement Project (HSEP) that assessed safety performance on two-lane highways in Beijing, China. Potential causal factors are identified based on proposed evaluation criteria, and primary countermeasures are developed against inferior driving conditions such as sharp curves, heavy gradients, continuous downgrades, poor sight distance, and poor clear zones. Six cost-effective engineering solutions were specifically implemented to improve two-lane highway safety conditions, including (1) traffic sign replacement, (2) repainting pavement markings, (3) roadside barrier installation, (4) intersection channelization, (5) drainage optimization, and (6) sight distance improvement. The effectiveness of these solutions was examined and evaluated based on Empirical Bayes (EB) models. The results indicate that the proposed engineering solutions effectively improved traffic safety performance by significantly reducing crash occurrence risks and crash severities.

Highlights

Improving two-lane highway traffic safety conditions is of practical importance and has attracted significant research attention within the last decade
This study presents research perspectives achieved from the Highway Safety Enhancement Project (HSEP) that assessed safety performance on two-lane highways in Beijing, China
The results indicate that the proposed engineering solutions effectively improved traffic safety performance by significantly reducing crash occurrence risks and crash severities

Summary

Introduction

Improving two-lane highway traffic safety conditions is of practical importance and has attracted significant research attention within the last decade. Labi [2] investigated the efficacy of roadway improvements in terms of crash reduction at various subclasses of rural two-lane highways using the empirical analysis method of the negative binomial modeling technique Most of these previous studies focused on only a single improvement, that is, widening shoulders, adding passing lanes, or installing center left-turn lanes. Lyon et al [9, 10] and Moreno et al [11] incorporated the Empirical Bayes method to determine the safety effectiveness of installing left-turn lanes and obtained operational effectiveness of passing zones from passing frequency Their results indicated that these were cost-effective treatments for two-lane rural highways. Six cost-effective engineering solutions were implemented to improve two-lane highway safety conditions: (1) traffic sign replacement, (2) repainting of pavement markings, (3) installation of roadside barriers, (4) intersection channelization, (5) drainage optimization, and (6) sight distance improvement. The results indicate that the proposed engineering solutions effectively improved traffic safety performance by significantly reducing crash occurrence risks and crash severities

Data Collection

Engineering Treatments Implemented

Safety Effects of Treatments

Findings

Conclusions