Pavement Markings
Overview
Functions and Limitations
Markings on highways and on private roads open to public travel have important functions in providing guidance and information for the road user. Major marking types include pavement and curb markings, delineators, colored pavements, channelizing devices, and islands. In some cases, markings are used to supplement other traffic control devices such as signs, signals, and other markings. In other instances, markings are used alone to effectively convey regulations, guidance, or warnings in ways not obtainable by the use of other devices. Markings have limitations. Visibility of the markings can be limited by snow, debris, and water on or adjacent to the markings. Marking durability is affected by material characteristics, traffic volumes, weather, and location. However, under most highway conditions, markings provide important information while allowing minimal diversion of attention from the roadway.
2011 MMUTCD, Section 3A.01
Initiatives
Optical Speed Bars Optical speed bars are white transverse markings on both sides of the lane that are placed at decreasing spacing in the direction of travel to give drivers the sense that they are traveling at a higher rate of speed to encourage slowing down. Previous installations in Michigan include EB I-94 Exit 12 (Sawyer Rd) in Sawyer and WB US-10 Business Route at M-20 in Midland.
Preformed Thermoplastic Route Shields
Preformed thermoplastic route shields are large markings in the lane that identify lane use ahead of a split or other confusing geometry. Previous installations in Michigan include the SB I-75/US-23 split in Flint and the diverging diamond interchange (DDI) at I-96 at Cascade Rd near Grand Rapids.
Curb/Island Painting
Curb/island painting is pavement marking material, including beads, that is applied to curb and raised island surfaces to provide positive guidance to traffic.
Delineator Pilot Project
A pilot project was initiated in late 2014 in cooperation with the Lansing TSC and the Charlotte Garage to evaluate alternatives to standard post mounted plastic buttons and enhanced guardrail options. The pilot project covers approximately 8 miles of NB and SB I-69 in the Charlotte area.
Sinusoidal Rumble Strips
Sinusoidal rumble strips, or “mumble strips†are a rolling sine wave pattern that is slightly recessed into the pavement surface. Sinusoidal rumble strips provide adequate sound and vibration to the driver but produce less exterior noise than traditional rumble strips. Different patterns are currently installed in Minnesota, Pennsylvania and California. MDOT is exploring the installation of a pilot section.
Statewide Rumble Strip Installation and Research
From 2008-2010, MDOT performed a statewide installation of centerline rumble strips on all appropriate non-freeway roads. The research project that followed took place in two phases. Phase 1 studied the impacts of rumble strips on driver behavior and Phase 2 studied the impact of rumble strips on crashes. A significant finding of phase 2 is that centerline rumble strips resulted in a 51% reduction in fatal lane departure crashes. Both reports can be found here:
RC-1575 - Impact of Non-Freeway Rumble Strips - Phase 1
RC-1627 - Evaluation of Non-Freeway Rumble Strips - Phase II
Ongoing Pavement Marking Research Project
An ongoing pavement marking research project is evaluating current pavement marking practices in Michigan and other states to identify best practices for increased program efficiency. The research project will conclude in Spring of 2017.
Innovative Materials
As new materials are developed, MDOT seeks to evaluate them for cost effectiveness, durability, wet night retroreflectivity, and speed of installation. It is important to evaluate both products that are competitors to existing products and brand new products that have never been tried in the state before. An example of a material that has been recently tested in Michigan is structured methyl methacrylate.
Wrong-Way Movement Treatments
PAVE-926 was created to help address wrong way movements at partial cloverleaf interchanges. The standard shows optional and required pavement marking and delineation treatments.