1 THE HIGHWAY SAFETY MANUAL Michael S. Griffith Federal Highway Administration July 26 th, 2004.
-
Upload
erick-dixon -
Category
Documents
-
view
218 -
download
0
description
Transcript of 1 THE HIGHWAY SAFETY MANUAL Michael S. Griffith Federal Highway Administration July 26 th, 2004.
1
H ighway afety
THE HIGHWAY SAFETY MANUAL
Michael S. GriffithFederal Highway AdministrationJuly 26th, 2004
2
H ighway afety
Growing Recognition …
Professionals do not have the needed tools to explicitly consider safety when making decisions related to highway facilities.
3
H ighway afety
What is the Highway Safety Manual (or HSM)?
• Purpose: to provide the best factual information and tools in a useful form to facilitate roadway planning, design, operations, and maintenance decisions based on explicit consideration of their safety consequences
4
H ighway afety
Targeted Users
• Primarily, analysts studying the impact of actions on roadway users– Planning, design and operations studies
• Secondary users– Management– Educational Institutions
5
H ighway afety
Research & Development• Relevant NCHRP efforts:
– NCHRP 17-18(4): HSM scoping study and development of prototype chapter on rural two-lane highways: Completed
– NCHRP Project 17-26: Development of Models for Prediction of Expected Safety Performance for Urban and Suburban Arterials: Started March 2003
– NCHRP 17-27: Prepare Parts I and II of the Highway Safety Manual – Started May 2004
– NCHRP 17-29: Safety Prediction Models for Rural Multilane Highways for Use in the Highway Safety Manual – Started May 2004
• Other efforts: SafetyAnalyst, IHSDM, and Human Factors Guide
6
H ighway afety
Resources
•Development of a Highway Safety Manual - Final Report, March 2004
•Development of a Highway Safety Manual – Research Results Digest, March 2004, Number 286
•Website – http://www.highwaysafetymanual.org/
7
H ighway afety
Outline for Initial Version of the HSM
Part I – Introduction and FundamentalsPart II – KnowledgePart III – Predictive MethodsPart IV – Safety Management of a
Roadway SystemPart V – Safety EvaluationGlossary
8
H ighway afety
Part I – Introduction and Fundamentals
9
H ighway afety
Part I - Chapter 1Introduction and Overview
1.1. Purpose1.2. Background on the Need for HSM1.3. Scope of the HSM1.4. Intended Audience1.5. Intended Use of the HSM1.6. Context for the HSM: Use and
Misuse of the Manual1.7. Nature of the HSM1.8. Organization of HSM
10
H ighway afety
Part I - Chapter 2Fundamentals
2.1. What is Safety?2.2. How Road Safety is Measured?2.3. Effect of Traffic Volume & Vehicle Mix 2.4. Safety Performance Functions and
Crash Modification Factors2.5. Human Factors in Road Safety2.6. Speed and Safety
11
H ighway afety
Part II - Knowledge
12
H ighway afety
Part II - Chapter 3Roadway Segments
3.1. Safety Effects of Highway Design Elements
3.2. Safety Effects of Traffic Control andOperational Elements
3.3. Pedestrian and Bicycle Safety on Roadway Segments
3.4. Safety Effects of Other Elements
13
H ighway afety
Part II - Chapter 4Intersections
4.1. Safety Effects of Intersection Design Elements
4.2. Safety Effects of Intersection Traffic Control and Other Operational Elements
4.3. Safety Effects of Other Intersection Related Features
4.4 Pedestrian and Bicycle Safety atIntersections
14
H ighway afety
Part II - Chapter 5Interchanges
5.1. Safety Effects of Interchange Design Elements
5.2. Safety Effects of Traffic Control and Operations Elements
15
H ighway afety
Part II - Chapter 6Special Facilities and Geometric
Situations6.1. Railroad-Highway Grade Crossings6.2. Construction and Maintenance
Work Zone Areas
16
H ighway afety
Part II - Chapter 7Road Networks
7.1. Introduction7.2. Safety in Transportation Network
Planning7.3. Safety in the Planning and Design of
Residential Neighborhoods and Commercial Areas
7.4. One-Way Systems and Turn Restrictions 7.5. Safety in Traffic Calming 7.6. Access Management7.7. Road-use Culture
17
H ighway afety
Part III – Predictive Methods
18
H ighway afety
Part III - Chapter 8Rural, Two-Lane Roads
8.1. Introduction8.2. Methodology8.3. Applications8.4. Example Problems8.5. References
Appendices
19
H ighway afety
Prototype Chapter 8 - Overview
• Scope: Estimates the safety performance of a rural two-lane highway segments and at-grade intersections
• Applications– Individual segments and intersections– Overall project
20
H ighway afety
Prototype Chapter 8 - Overview
• Explicitly Considers:– Roadway Segments (ADT, lane & shoulder
width, shoulder type, horizontal curvature, grade, driveways, and roadside design)
– Intersections (type of control, number of approach lanes & volume, sight distance, skew angle, and turn lanes)
21
H ighway afety
Part III - Chapter 9Rural, Multi-Lane Highways
9.1. Introduction9.2. Methodology9.3. Applications 9.4. Safety Issues Not Explicitly addressed by
the Methodology9.5. Example Problems9.6. References
22
H ighway afety
Part III - Chapter 10Urban/Suburban Arterial Highways
10.1. Introduction10.2. Methodology10.3. Application10.4. Safety Issues Not Explicitly addressed
by the Methodology10.5. Example Problems10.6. References
23
H ighway afety
Part IV – Safety Management of a Roadway System
• Chapter 11. Identification of Sites with Promise
• Chapter 12. Diagnosis of the Nature of Safety Problems at Specific Sites
• Chapter 13. Selection of Countermeasures to Reduce Accident Frequency and Severity at Specific Sites
• Chapter 14. Economic Appraisal of all Sites under Consideration
• Chapter 15. Prioritized Rankings of Improvement Projects
24
H ighway afety
Part V – Safety Evaluation
25
H ighway afety
Part V - Chapter 16Safety Evaluation of Implemented
Measures16.1. Introduction16.2. Why Evaluate?16.3. Data Needs and Limitations16.4. Approach to Conducting A Valid
Evaluation
26
H ighway afety
When available?
• First edition expected to be released in 2007 or 2008.
27
H ighway afety
Data Requirements for HSM
•Data Requirements Guide will be developed.
28
H ighway afety
Requirements
R = Data is Required and there is no default value (the process would be incomplete without the user entering the data).
RD = Data is Required and there is a Default Value if the user does not enter the data.
O = Data is used by the process if available but is Optional.
29
H ighway afety
Basic Data Needs
•Crash
•Roadway
•Traffic
30
H ighway afety
Prototype Chapter (Rural, Two-Lane Roads)
Crash Data
Traffic Data
Roadway Data
31
H ighway afety
Crash Data - Required
•Crash History Data
Frequency and Severity Data by Location and by Year
32
H ighway afety
Traffic Data - Required
Average Daily Traffic by location
33
H ighway afety
Roadway Data – Horizontal Data ElementsTangentSimple CurveSpiral CurveDeflectionHeading CoordinateStation Equation
34
H ighway afety
Roadway Data – Vertical
Data Elements
Vertical Point of IntersectionElevationTangentCurve
35
H ighway afety
Roadway Data – Cross Section
Data Elements
Pavement (Cross Slope)Shoulder (Width and Type)
36
H ighway afety
Roadway Data – Lane Group
Data Elements
ThruPassingTurnTwo-way left-turnClimb
37
H ighway afety
Roadway Data – Roadside Group
Data Elements
Driveway Density
Hazard Rating
38
H ighway afety
Intersection DataTraffic ControlNumber of LegsIntersection Sight DistanceNumber of approach lanes & volumeTurn lanesSkew angle