SWUTC Research Project Description
Title of Project: Causes and Patterns of Bicycle / Vehicle Conflicts at Freeway Interchanges
Project Number: 161043
Principal Investigator:
Fengxiang Qiao
(713) 313-1915
P.I. Affiliation: Texas Southern University
Project Monitor:
Alan Clark
Houston-Galveston Area Council
3555 Timmons, Suite 120
Houston, TX 77027
(832) 681–2508
Project Status: Active
Date Started: 9/1/09
Estimation Completion Date: 8/31/10
Estimated Cost - Current Fiscal: $20,000
Estimated Cost - Total Planned: $20,000
Project Summary:
Project Abstract:
The city bikeway network often intersects with freeway interchanges in metropolitan areas such as Houston. Due to the unique traffic features and the complicated geometric conditions, it is likely that there are more bicycle/vehicle collisions and potential conflicts at freeway interchanges. This observation can be further verified through the review of conflict records and associated collision diagrams. To understand the causes, patterns, potential conflicts and concerns under this situation will help to provide better services to bicyclists during planning and operation stages. The principle research question is whether there are more bicycle/vehicle collisions near freeway interchanges and what are the causes and patterns of such collisions. More specifically, the detailed research questions are: (1) whether there are more bicycle/vehicle collisions at freeway interchanges than on similar roadway classes; (2) what are the significant causes (speeding, unsafe lane change, etc.) of these collisions; (3) what are the pattern(s) with regard to the contributing factors for collisions between bicycles and vehicles near interchanges; (4) what are the concerns that are increasing or are unique for bicyclists to traversing areas near freeway interchanges; (5) what types of computer aided visualization tools could be provided to engineers, policy makers, and the public for their much better understandings of potential conflicts and design issues.
Project Objectives:
The goal of this research is to evaluate the causes and patterns of bicycle / vehicle conflicts at freeway interchanges. The research objectives are to: (1) exam the conflict data in typical interchanges; (2) identify the significant causes (speeding, unsafe lane change, etc.) and patterns of these collisions; (3) identify the concerns that are increasing or are unique for bicyclists to traversing areas near freeway interchanges; (5) identify suitable computer aided visualization tools.
Task Descriptions:
Task 1: Conduct Literature Review on Existing DTA models
In this task, the literatures related to bicycle conflict investigation and analyses, especially related on bicycle-motor vehicle conflict analyses at freeway interchanges will be carefully scanned. Scientific papers, articles, project reports, handbooks and websites will be searched to acquire a comprehensive understanding of the state-of-the-art/practice.
Task 2: Obtain Bicycle Conflict Data from H-GAC
The research team will check with H-GAC on available bicycle related conflict data in H-GAC area. The conflict data will not only be focused on freeway interchanges, but also on other roadways for comparison purposes.
Task 3: Analyze Conflict Rate Based on the Conflict Data
The bicycle related conflict data will be carefully analyzed in this task. Conflicts at interchanges will be analyzed separated with those on other types of roadways and segments. Conflicts of bicycles with motor vehicles for different movement directions will be carefully analyzed. Necessary charts will be plotted to better illustrate these conflicts.
Task 4: Identify the Causes, Patterns and Concerns Related to Bicycle Conflict Data at Freeway Interchanges
Based on the analytical results of bicycle related conflict data at freeway interchanges and in other locations, the causes (speeding, unsafe lane change, etc.), patterns and concerns of these conflicts will be carefully re-analyzed. Suitable statistical tools such as ANOVA test, the probability analytical software @Rick, etc. will be used if necessary.
Task 5: Identify Suitable Computer Aided Visualization Tools to engineers, policy makers, and the public
In the task, the suitable computer aided visualization tools will be identified for engineers, policy makers and even the public to use. It is possible that different such tools will be identified for different types of users. Recommendations to possible treatments that will improve the safety of bicyclists at freeway interchanges will be proposed.
Task 6: Document Research Results
All the numerical and demonstration results will be documented. A comprehensive report will be prepared to summarize the findings and possible improvements of the whole process.
Index Terms: