Mn/DOT OTSTOffice of Traffic, Safety, and

Technology

Mitch Bartelt, PEPavement Marking

Engineer

Ken E. Johnson, PEPavement Marking

and Work Zone Engineer

What are pavement markings? MnMUTCD Big picture Colors, patterns and widths Types of markings

What are pavement markings made of? Materials used and why

Exciting new implementations!!! Rumble stripEs Wet-reflective Grooving Others

MN Statute 169.06 – “The commissioner shall adopt a manual … for a uniform system of traffic-control devices … for use upon highways within this state.”

Example of importance: Up until the 1971 version of the Federal

MUTCD, white was allowed as a color for centerlines in the United States. The 1971 version standardized yellow for centerlines following decades of debate.

Communication system for drivers Provide traffic control Provide guidance Supplement other traffic control

devices

Longitudinal lines Parallel to the direction of travel

Transverse lines Perpendicular to the direction of travel

Arrows, words and symbol markings Special markings

Colors, widths and patterns are similar to the alphabet

When put together, you get a ‘word’ – particularly with longitudinal and transverse markings

Example: - Yellow - Normal width - Double lineCenterline in a no passing zone

Delineate vehicular paths of travel (tell cars where to go)

Marking: Centerlines Lanes of travel Edgelines

Basic concepts of colors, patterns and widths Yellow lines

Delineate the separation of opposing traffic flows Or mark the left edge of pavement of one-way

roadway White lines

Delineate the separation of same direction traffic flows Or mark the right edge of pavement

Solid lines are restrictive Broken lines are permissive (MN 10’ line – 40’ gap) Dotted lines have multiple meanings (context) Double lines – maximum restrictions Width indicates degree of emphasis

Always yellow and normal width

Patterns will give message: Broken and solid Single and double Passing vs. no passing Special uses of certain

lanes

TWLTL Reversible

Always yellow and normal width

Patterns will give message: Broken and solid Single and double Passing vs. no

passing Special uses of

certain lanes

Separate lanes in same direction

Always white Patterns will give message

whether crossing is: Permitted (Broken) Discouraged (Solid) Prohibited (Double solid)

Special dotted patterns Lane is exit only or will end Lane line extensions

Delineate edge of travelled way Always solid Color indicates roadway direction

White always on right side Yellow on left for one-way roadway

Ramp or divided highway White on left for two-way roadway

Width indicates degree of emphasis Used in gores and drop lanes Wisconsin uses to indicate turn lanes

Stop line

Crosswalks Yield line

Cross hatching Speed hump

Parking spaces

There were 22642 total miles striped on MnDOT trunkline highways in 2008 3502 miles of construction striping 19140 miles of maintenance striping

MnDOT spent a total of $12.1 million in 2008 on pavement markings $5.7 million of construction striping $6.4 million of maintenance striping

Our laserlux van took 7102 miles of retro-reflective readings in 2009

Retroreflective elements Retroreflective elements (beads)(beads)

Liquid pavement markingsLiquid pavement markings ““Beads” added during Beads” added during

applicationapplication LatexLatex EpoxyEpoxy

Preformed polymer tapePreformed polymer tape ““Beads” imbeddedBeads” imbedded

Preformed thermoplasticPreformed thermoplastic Symbols and messagesSymbols and messages

As an agency, MnDOT primarily As an agency, MnDOT primarily uses three types of products:uses three types of products:

Latex PaintLatex Paint EpoxyEpoxy Preformed Polymer TapePreformed Polymer Tape

MaterialMaterial Approximate Approximate Expected LifeExpected Life

Latex PaintLatex Paint 1+ year1+ year

EpoxyEpoxy 3-5 years3-5 years

Preformed Polymer TapePreformed Polymer Tape Up to 10 yearsUp to 10 years

Pros: The cheapest option Easiest to apply

Cons: Least durable Most susceptible to wear from higher traffic

volumes Will likely need to be replaced every year

Pros: More durable than latex Cheaper than tape

Cons: Lacks UV stability More complicated than latex paint to apply More expensive than latex

Pros: Durable (if applied correctly) Better retroreflectivity than other products

Cons: More expensive than other products Product failure can cause you to lose entire marking

April 24, 2009 30Operations Division

(Construction + Maintenance)

* Does Not Include Pavement Messages

0

5000

10000

15000

20000

25000

Line-Miles

2001 2002 2003 2004 2005 2006 2007 2008

Year

Latex Epoxy Tape

April 24, 2009 31Operations Division

Total Striping Expenditures*(Construction + Maintenance)

* Does not include Pavement Messages

$-

$5,000,000

$10,000,000

$15,000,000

$20,000,000

$25,000,000

Expenditures

2001 2002 2003 2004 2005 2006 2007 2008

Year

Tape

Epoxy

Latex

Materials we’re experimenting with OTST safety research with pavement

markings Rumble stripEs Wet-reflective markings Grooving

Precut Thermoplastic Pavement Messages

Polyurea MMA (Methyl

Methacrylate) Wet-reflective epoxy

elements

April 24, 2009 34 Operations Division

Enhanced Edgelines to reduce run off the road crashes Ground-in wet reflective paint

100 miles in District 4 on I-94 6” wide lines

300 miles statewide Rumble stripEs

300 miles statewide

Provides wet-reflectivity Provides tactile warning

Distracted driver Limited visibility

conditions Snow Fog Etc

NCHRP 641 – Rural Roads 9 percent reduction in

total crashes 12 percent reduction in FI

crashes 30 percent reduction in

total target crashes 44 percent reduction in FI

target crashes

NCHRP 641 – Shoulder rumble strip data

Rural 2-lane roads 15 percent reduction in

SVROR crashes 29 percent reduction in

SVROR FI crashes Rural multi-lane

divided 22 percent reduction in

SVROR crashes and 51 percent reduction in

SVROR FI crashes

Wet-reflective elements added to epoxy or latex, resulting in a wet-reflective marking

Epoxy With Wet-

Reflective

Elements

Epoxy With

Standard 1.5 Index Beads

We know that the marking lasts longer and stays protected

Is grooving in materials cost-effective? Depends…

April 24, 2009 40 Operations Division

Drivers complained about lack of daytime visibility of markings on new 35W bridge

Each tape skip was tagged with black epoxy as a late-season countermeasure

Omnibus 2008 n= 800 Statewide unless otherwise noted