Design and Implementation of Rumble Strips North Dakota Department of Transportation Matt Gangness P.E., Technical Supp

1. Design and Implementation of Rumble StripsNorth Dakota Department of TransportationMatt Gangness P.E., Technical Support � Design Division

2. Cost effective road safety feature that alerts drivers of potential danger through audible rumbling/vibrations Alerts distracted, drowsy, or fatigued drivers What are rumble strips?

3. Rumble Strips? Rumble Stripes? Rumble StripEs? Rain Bright Edge Lines? Audio Tactile Profiled Markings? Singing Shoulders? SRS? CLRS? Full-Lane Rumble Strips? Vocabulary�.I think�.

4. Shoulder Rumble Strips (Milled) Rumble strip located on shoulder, offset from edgeline Edgeline Rumble Strips (Milled) Rumble strip located within edgeline pavement marking Centerline Rumble Strips (Milled) Rumble strip located on centerline and within pavement marking Saw Slotted Rumble Strips at T-Intersection Full driving lane width rumble strips for stop conditions NDDOT Rumble Strips

5. Washington State State report rumble strips on state highways cut accidents by nearly 60% MNDOT � centerline rumble strips cross section analysis 73% lower rate of fatal and very severe crashes 42% lower crash rate overall 19% reduction in crash density (# of crashes per mile) NCHRP 641 Shoulder rumble strips 15% reduction in SVROR crashes 29% reduction in SVROR FI crashses Why Rumble Strips? Safety Benefits

6. Complaints Annoying Invasive Loud Disruptive Motorcycles & Bicyclists? Why are they needed? FOR YOUR SAFETY! Negative Public Perceptions?

7. Reference NCHRP Report 641

8. Shoulder Rumble Strips: �the most common dimensions of milled shoulder rumble strips used throughout the United States are: -Length 16� -Width: 7� -Depth: �� to ?� -Spacing: 12� (NCHRP 641, pg. 138) �For milled rumble strips, typical lengths of patterns are 12� and 16� (NCHRP 641, pg. 138) �Given their proven safety benefits for several roadway types� �the low cost of installation, and relatively few concerns (i.e., noise, bicyclists, pavement performance, and visibility), shoulder rumble strips are considered appropriate for installation along a range of roadway types� (NCHRP 641, pg. 143) �rumble strips can be designed with relatively narrow lengths (e.g., 6 in.) and still generate the desired sound level differences in the passenger compartment.� (NCHRP 641, pg. 144) �Specific features or areas along the shoulder roadway where it is common to discontinue or interrupt shoulder rumble strips include the following: -intersections, driveways, and turn lanes -entrance and exit ramps -structures (i.e. bridges) -where lateral clearance is limited due to adjacent guardrail, curb, or other obstacles -residential areas -catch basins and drainage grates -pavement joints -median crossings� (NCHRP 641, pg. 140) Reference NCHRP Report 641

9. Shoulder Rumble Strips: �Primarily to better accommodate the needs of bicyclists, consideration may be given to providing intermittent gaps in the rumble strip patterns, compared to a continuous pattern. Based upon research and current practice, it is common to provide periodic gaps in the rumble strips of 10� or 12�, in 40� or 60� cycles. Provision of intermittent gaps enables bicyclists to maneuver from one side of the rumble strip to the other without having to encounter the indentations/grooves.� (NCHRP 641, pg. 139) �Agencies address bicycle considerations in several ways, including: (a) not installing rumble strips on roads with significant bicycle traffic or if the roadway is a designated bicycle route, (b) adjusting the dimensions of the rumble strips, (c) adjusting the placement of the rumble strips, (d) adjusting the minimum shoulder width and/or lateral clearance requirements, and/or (e) providing gaps in periodic cycles.� (NCHRP 641, pg. 136) Reference NCHRP Report 641

10. Centerline Rumble Strips �concerns have been expressed about the potential of motorcyclists losing control of their motorcycles when they encounter centerline rumble strips. Based upon a recent study, conclusive evidence exists to show that centerline rumble strips add no measurable risk to motorcyclists. Therefore, there is no need to consider potential adverse effects for motorcyclists when developing a centerline rumble strip policy.� (NCHRP 641, pg. 141) �The following are the most common dimensions of milled centerline rumble strips used throughout North America: -Length: 12� or 16� -Width: 7� -Depth: �� -Spacing 12� (NCHRP 641, pg. 141) �concerns over the visibility and retroreflectivity of pavement marking should not prohibit the use of centerline rumble strips.� (NCHRP 641, pg. 141) �The following are specific features or areas along the roadway where it is common to discontinue or interrupt centerline rumble strips: -intersections and driveways -passing zones -structures (i.e. bridges) -residential areas� (NCHRP 641, pg. 142) �there is no conclusive evidence to recommend that centerline rumble strips should be discontinued within passing zones.� (NCHRP 641, pg. 142) NCHRP Report 641

11. NDDOT Standard Drawing D-960-1

12. NDDOT Standard Drawing D-960-2

13. NDDOT Standard Drawing D-960-3

14. NDDOT Standard Drawing D-960-4

15. NDDOT Standard Drawing D-960-5

16. Questions? Matt Gangness, P.E. NDDOT - Design Division 608 East Boulevard Avenue Bismarck, ND 58505-0700 Phone:� 701-328-2524 Fax:� 701-328-0310 Email:� mgangness@nd.gov