mn/dot otst office of traffic, safety, and technology
TRANSCRIPT
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