October 11, 2016 Yung Koprowski, PE, PTOE Project Manager, Lee - - PowerPoint PPT Presentation

October 11, 2016

Yung Koprowski, PE, PTOE Project Manager, Lee Engineering

Overview

• The UIIG story
• UIIG information
• UIIG toolkit
• Using the UIIG

The UIIG Story

NCHRP Project 03-104

• Problem statement:

 Develop comprehensive guide to enhance safe

• peration for all users of unsignalized

intersections  The Guide should be practical and multimodal and aid practitioners in selecting design,

• perational, maintenance, enforcement, and other

types of treatments to improve safety, mobility, and accessibility

• NCHRP Sr. Program Officer— Ray Derr

UIIG project team

• Independent

consultants:

 Tony Giancola  Capt. Glenn Hansen  Frank Spielberg

• NCHRP Oversight Panel
• Technical Advisory Group

What is an unsignalized intersection?

• Any at-grade junction of two or more public

roads whose traffic movements are not controlled by a traffic signal interchanges signals

Why the UIIG

21K

fatal intersection crashes

7 of 10

w/o traffic signal

Majority

locally-maintained

2010 - 2012

Many agencies lack professional transportation engineers

Why the UIIG

• Recognition of nationwide safety issue
• NHTSA data shows a 7.7 percent increase in

motor vehicle traffic deaths in 2015. An estimated 35,200 people died in 2015, up from the 32,675 reported fatalities in 2014.

• Recognition of local road/local agency need

Target audience of UIIG

• Local road-owning

agencies

• Majority of

unsignalized intersections under their control

• Especially useful to

those without transportation engineers on staff

• State DOTs, large local

agencies, consultants

• Comprehensive nature
• Provides references on

variety of intersection- related topics

• Valuable resource for

individuals without safety training

PRIMARY SECONDARY

Benefits of web-based UIIG

• Allows continuous revisions (e.g., MUTCD updates)
• Enables user interaction  more likely to be used
• Offers hyperlinks to other internet resources that

provide additional information on variety of related topics

• Capitalizes upon internet-based innovations such as

aerial imagery & street-level photography to illustrate real-world examples

• Conducive to sharing tools to assist user in

addressing intersection safety

UIIG Structure—Two main sections

UIIG Information

• Background technical

content that is “static” but will change as necessary

• First-time UIIG users should

become familiar with content

• Relies heavily on links to

primary resources that provide further details

Types of Unsignalized Intersections

UIIG intersection typology

• Traffic control

Uncontrolled YIELD STOP

Uncontrolled intersection

• No approach controlled by STOP or YIELD sign
• Per § 11-401 of Uniform Vehicle Code:

 Driver of the vehicle on the left shall yield the right-

• f-way to the vehicle on the right.
• Driver must also yield to any vehicle or pedestrian

already in intersection

• Frequently found in residential areas and very rural

areas

Yield-controlled intersection

• Entrance into intersection

from one or more approaches controlled by YIELD sign

• Drivers must decrease speed

and concede R/W to users in the intersection

• Adequate sight distance

required

• Roundabouts are only

intersections at which YIELD signs control all approaches

Stop-controlled intersection

• Entrance into intersection

from one or more approaches controlled by STOP sign

• Complete stop always

required

• Stop condition can apply

to all approaches or minor road only

Nontraditional designs

• Alter customary vehicular paths to reduce the
• no. and/or severity of conflict points
• Two main unsignalized groups:

 Circular intersections:

 Full roundabout  Mini-roundabout  Residential traffic circles

 U-turn-type intersections (i.e., RCUT, J-turn)

Users of Unsignalized Intersections

Unsignalized intersection users

• Compose largest

user group at most intersections

• Vehicle

characteristics must be considered

• Majority of UIIG

treatments target drivers

Motor Vehicle Operators

• Bicycle travel on the

rise in U.S.

• Must adhere to rules
• f road when riding
• n it
• Skill & experience

vary widely

• Vulnerable users

Bicyclists

• Skill & experience

vary

• Surrounding land use

affects nos. and demographics

• Kids, seniors, persons

w/ disabilities are

• ften of particular

concern

• Vulnerable users

Pedestrians

Improvement Process

Improvement process

• UIIG’s purpose:

 Assist agencies in addressing problems at unsignalized intersections

• Problems can relate to safety, operations, or

access for motorists and non-motorists

• Problem identification and treatment

implementation should follow basic improvement process, regardless of agency size

Improvement process

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

1 - Identify problem intersection(s)

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

• Nature of intersection problem can vary …

 Single intersection  Several intersections along a corridor  Jurisdiction-wide

1 - Identify problem intersection(s)

1 - Identify problem intersection(s)

• Agencies learn of problems in several ways:

a) Notification by public * b) Observations during police patrol or crash investigations * c) Systematic monitoring by agency staff d) Crash data analysis

* Need communication channels & protocols

Improvement process

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

2 - Analyze the intersection

• Once potential problem intersection has been

identified, it should be analyzed via …

a) Crash analysis b) Site review and observation

2a - Collision diagrams

 Crash type  Direction of travel  Approximate location

2a - Crash tabulations

• Develop tabulations across multiple variables

 Day vs. night  Day of week/time of day  Driver condition (belt, alcohol)  Driver age  Crash type

• Right-angle
• Left-turn
• Rear-end (major/minor)
• Head on
• Sideswipe, same direction
• Sideswipe, opposite direction
• Pedestrian
• Bicyclist

2b - Site review & observations

• Internet imagery is valuable, but site visit is necessary
• RSA principles offer guidance on field approach

2 – Analyze the intersection



Crash

Analyses

Field

Observations Potential

Problem Types

Improvement process

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

3 - Identify potential treatments

• This step aligns with the UIIG’s main purpose:

 Describe various treatment alternatives applicable to unsignalized intersections

• 75 treatments identified, ranging from low-cost

traffic control devices to more extensive road construction

 71 engineering  4 enforcement  Education efforts also discussed

• More on this later …

Improvement process

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

4 - Select & implement treatment(s)

• Step 3 likely identified multiple treatment
• ptions
• Benefit-cost analysis required

Estimated

Benefits

• Crash reduction
• Operational improvement

Estimated

Costs

• Construction & R/W
• Maintenance / lifecycle

4 - Select & implement treatment(s)

• Because many UIIG treatments are low-cost,

potential exists to apply on a wide scale

• Look for opportunities to apply systemic

approach

 Identify combinations of risk factors that may increase likelihood of severe crash even if one hasn’t

• ccurred

 Interjects proactive approach  May be applicable when crashes are widely scattered over many intersections (e.g., in very rural areas)

4 - Systemic example

• Consider STOP AHEAD

pavement marking

 Published research:

 Particularly effective at 3- legged and all-way stop- controlled  Low-cost strategy can easily achieve 2:1 B-C ratio

 By identifying road and traffic characteristics of some hot spot intersections, this low-cost strategy could be more broadly applied across jurisdiction

Improvement process

Identify problem intersection(s) Analyze location(s) to quantify & characterize problem Identify potential treatments that may address problem Select/implement cost-effective treatment(s) Monitor over time & evaluate treatment’s effectiveness

5 - Monitor effectiveness over time

• Improvement process does not end at

implementation

• Evaluation should be conducted to determine if

situation has improved

• Consider …

 Not only crash data but also perspective of law enforcement, others  Follow-up with person(s) who originally notified agency of problem

• Disseminate findings

Types of Problems

• Nature of intersection problem can vary …
• Because UIIG is to identify treatment alternatives to

solve problems, problem types are key

• 10 general problem types are described:

 Definition  Explanation  Example

UIIG problem types

UIIG problem types

• A. Inappropriate Traffic Control
• B. Inadequate Visibility of Intersection or Traffic

Control Devices

• C. Inadequate Intersection

Sight Distance

UIIG problem types continued

• D. Inadequate Guidance for Motorists
• E. Excessive Intersection Conflicts
• F. Vehicle Conflicts with nonmotorists

UIIG problem types continued

• G. Poor Operational Performance
• H. Misjudgement of Gaps in Traffic

 Request for Traffic Signal

I. Speeding  Exacerbates all other problems J. Noncompliance with Traffic Control Devices

Other factors

• Problems can be cast in different ways
• Other characteristics that can contribute to

intersection problems include:

 Geometry  Pavement surface and skid-resistance  Lighting  Drainage  Maintenance

UIIG Information

Types of Treatments

Treatments overview

• UIIG’s mission:

 Assist in determining appropriate treatments to improve safety, operations, and access at unsignalized intersections

Treatments types

• 75 treatments described in UIIG
• Engineering [71]

 Traffic control devices  Geometric  Shoulder & roadside

• Enforcement [4]
• Education

 General discussion of its role in

• ther E’s

 Pavement surface  Other

UIIG treatment fact sheet PDFs

Description Conditions addressed Considerations for installation Links to external resources Link to internet mapping of several actual applications Targeted crash types Problem types addressed Photographs Link to CMF Clearinghouse website Relevant MUTCD/ Green Book sections

Selection of Appropriate Control

Selecting intersection control

• MUTCD  control selection is engineering

judgment

• Uncontrolled

 MUTCD does not specify when STOP or YIELD signs are not needed

• Yield-controlled

 MUTCD identifies five conditions

• Stop-controlled

 MUTCD describes stop and all-way stop conditions

Selecting appropriate intersection control

• Links & references

to MUTCD and Uniform Vehicle Code

• Brief discussion of

roundabouts and

• ther circular

intersections

ADA & Pedestrian Considerations

ADA & pedestrian considerations

• Primary features:

 Curb ramps  Pedestrian refuge islands  Crosswalk markings  Sidewalk

UIIG Toolkit

UIIG Toolkit

• Developed to provide

applications and examples related to enhancement of unsignalized intersections

• Three “tools”:

 Citizen traffic service request form  Assessment and inventory form  Treatment selection tool

Citizen traffic service request form

• Available from Toolkit

as PDF or Word document

• Meant for agencies

with no formal mechanism to solicit public feedback

• Purpose is to serve as

conversation-starter for agency in establishing feedback method

Intersection assessment & inventory form

• Two primary purposes:

1) Present comprehensive list of data elements related to the safety, operations, and access of unsignalized intersections 2) Provide user-friendly interface through which data can be entered and catalogued

• Downloadable Microsoft Excel spreadsheet

 Includes detailed instructions  10 data tabs spanning multiple subjects  Final tab compiles all data inputs into single table  Most elements are optional (i.e., can be hidden)

Treatment selection tool

• Purpose:

 To provide users with treatment alternatives

• Four ways to access UIIG treatments:

1) Complete list of all 75 2) Keyword search 3) Treatment alternatives matrix

• Utilizes problem type/treatment type combo

4) Treatment alternatives filter

• Accepts user input on 1 – 6 subjects related to

intersection

www.ite .or g/ uiig

Questions?

• UIIG background and

development:

• Hugh McGee, Sr., PhD, PE

mcgeeforsafety@aol.com

• Jonathan Soika, PE

jsoika@vhb.com

• Mike Cynecki, PE, PTOE

mcynecki@lee-eng.com

• Yung Koprowski, PE, PTOE

ykoprowski@lee-eng.com

• UIIG website,

hyperlinks, maintenance, revisions:

• uiigfeedback@ite.org