Rumble Strips

Placing rumble strips is a work practice that act as an intervention to reduce struck-by hazards by creating tangible physical vibrations and noise to alert drivers to impending obstacles.

Description:

Temporary rumble strips consist of several raised bars arranged along a traffic lane to create tangible physical vibrations and noise to alert drivers to impending obstacles. These are usually made of plastic/polymer (e.g., recycled rubber), a strong and durable material that won’t be damaged or diminished as traffic runs over it. 

Transverse rumble strips run along the entire driving lane. These types of rumble strips are usually temporary, especially when used in a construction work zone.  The ease of installing and removing rumble strips have made them practical for use in work zones. The American Traffic Safety Services Association has developed a guide for use of temporary rumble strips in work-zones and classified them into 5 types. The main features of each type are as follows: Preformed thermoplastic strips are easy to install as these pre-cut products can be placed regardless of the temperature of the road. Pavement Marking tapes could be placed on top of each other until reaching the desirable thickness. Adhesive strips are produced with an adhesive backing which makes the installation and removal process easier while manually adhesive products can be found in different colors to improve visual detection. The last type, portable reusable strips, are ideal for short-term work-zones. Table 1 provides more information about different types of rumble strips that can be used near work-zones and their installation and removal procedures.

 

Table 1. Types of Temporary Rumble Strips and Their Installation Procedures

Features

Type

Preformed Thermoplastic

 

Source: Ennis-Flint, 2013

Pavement Marking Tape

 

Source: Swarco Industries, Inc., 2013

Adhesive

 

 

Source: Advanced Traffic Markings, 2013

Manually Adhesive

Source: Swarco Industries, Inc., 2013

Portable Reusable

Source: Plastic Safety Systems, 2013

Adhesive

Polymer materials that are melted and fused to the pavement

Manufactured with a pre-applied adhesive

Manufactured with a removable adhesive backing

Require the application of a bonding/ fastening agent such as adhesive cement, glues, or screws

Stay in place under their own weight, require no adhesives or fasteners

Assembly

Pre-cut strips manufactured in a two-part system: base layer & rumble bar

Comes in manufactured rolls

Manufactured plastic strips come in 50 ft. rolls

Manufactured plastic rumble strips in pre-cut lengths

Modular plastic strips manufactured in 45 in. long sections of 35 lbs. each

Typical Size

3 ft. long

Base: .125 in. thick, 4, 6, or 8 in. wide

Bar: .25 in. thick, 2 in. wide

Can be layered and built up to desired thickness

Various length

0.25 in. thick

4 in. wide

 

4-6 ft. long,

6 in. wide,

0.25 in. thick

3 sections connect to form an 11 ft. rumble strip (105 lbs. total); 13 in. wide, .75 in. thick

Color

Black White Yellow Orange

White Black Yellow Others

Orange Black White

White (reflective available)

Orange (reflective available)

Black

Black

Installation

Manpower

3 workers

2 to 3 workers

2 to 5 workers

4 workers

2 workers

Time

2 - 3 days

Varies based on thickness

30 - 40 min.

45 - 75 min.

25 min.

Equipment*

Industrial heat torch

Propane

sealer (concrete)

Paint roller (concrete)

Utility knife

Tamper cart

Saw

Tamper cart

Adhesive cement

Tamper cart

None

Road/Ambient Temperature Requirements

None

≥ 32 ̊ F

≥ 40 ̊ - 50 ̊ F

≥ 40 ̊ F

≥ 50 ̊ F

0 ̊ - 180 ̊ F

Removal

Manpower

2 to 3 workers

2 to 3 workers

1 to 2 workers

1 to 2 workers

1 to 2 workers

Time

A couple of hours

Variable

A few minutes

< 10 min.

A few minutes

Equipment

Torch or blaster

None

Utility knife

Shovel

None

Reusable

No

No

Yes

No

Yes

Additional Features

Speed Ratings

Max unknown

Max unknown

Max unknown

Max unknown

70 mph or less

Shelf Life

1 - 2 years

1 year

1 year

unknown

3 - 5 years

*Additional equipment may be required for cleaning or marking the roadway prior to rumble strip installation.
(source: https://www.workzonesafety.org/training-resources/fhwa_wz_grant/atssa_temporary_rumble_strips/)

To use rumble strips, one needs to make a professional judgment regarding their applicability, location, and installation process. The duration of work-zone activities, for instance, plays a significant role in selection the right type of products: thermoplastic rumble strips are only recommended if the process would take more than 3 days, while portable strips are suitable in short-term (within hours) road works. The configuration of strips is also pertinent to the performance of this solution. For instance, El-Rayes et al. (2013) pointed out that four configuration factors (i.e., spacing of rumble strips, type of rumble strips, type of vehicle, and vehicle speed) are correlated with the produced sound levels and consequently effectiveness of rumble strips. 

 

 


Risks Addressed:

Work zones near roadways could create various changes in road conditions that might be a surprise to drivers, such as unexpected change in alignment of lanes, a reduction in speed limits, a lane closing, new merge patterns, visual obstruction ahead, and even night-time work zones. Near work zones, inattentive drivers are exposed to the risk of hitting construction workers or equipment, resulting in injuries to the driver as well as construction workers. Rumble strips could be used to increase awareness of drivers regarding upcoming conditions, enabling them to reduce vehicle speed and follow the change in traffic due to a work zone.


How Risks are Reduced:

Vibration and noise can make drivers more alert, which in turn will significantly lower the chance of struck-by accidents near or in a work zone. Rumble strips can create enough vibration and noise in a moving vehicle to warn the driver to slow down, move over, or stop. While rumble strips do not deliver a specific message, they can alert drivers that conditions ahead are changing. Sun et al. (2011) revealed that temporary rumble strips increase braking by more than 10% and that the brake speed on average slows by 3.71 mph. They also found that speed compliance increased about 2.9% when strips were in use.


Effects on Productivity:

Rumble Strips have a very small effect on productivity. They are easy to install and remove and can be reused, as well. 


Additional Considerations:

Studies have shown that for greatest effectiveness, rumble strips need to be used together with other traffic control devices. This allows the rumble strips to do their main job of alerting drivers and bringing them to a high attention level so they can see a “caution sign” (e.g., slow speed ahead).

During this process, it is also important to think of the surroundings of the work zone to minimize disturbances to residents or businesses close to the work zone.

The following recommendations are provided by FHWA regarding the installation of rumble strips (Figure 2):

1.       Rumble strips should be between 7mm and 13mm thick and should be in a set of six spaced a maximum of 2.7 meters apart. At 50 mph or less, it is recommended to have gaps of 1.8 meters to 2.4 meters between rumble strips. At speeds greater than 50 mph, rumble strips can be spread strips 2.1-2.7 meters apart. Regular spacing between the singular strips could seem to drivers like regular control joints in the pavement (Figure 3). Irregularity in spacing is necessary to eliminate that misconception and properly alert the driver. Higher speeds require wider spacing between sets to provide enough time for drivers to reduce speed and become aware of the upcoming work zone area.

2.       Installation of temporary rumble strips should closely follow the department’s or manufacturer’s regulations/instructions, including details on air and pavement temperatures. If moisture is present in the air or on the pavement, cleaning of the pavement as well as choosing the proper adhesive are important.

3.       Temporary rumble strips should be used only when necessary. If audible and tactile warnings need to be provided for the safety of the workers or drivers, then rumble strips are highly recommended. Possible situations include detours, splitting lanes, lanes turning into exit/turn only, single lane traffic, stop light ahead, abrupt reduction in speed limit, and other varying traffic patterns.

Figure 2. Example of setting up a set of temporary rumble strips. (FFWA-NJ-2013-002 Report)

Figure 3. A picture of temporary rumble strips before a work zone.

(https://www.workzonesafety.org/training-resources/fhwa_wz_grant/atssa_temporary_rumble_strips/)


Contributors:

Behzad Esmaeili, Ph.D. - University of Nebraska- Lincoln

Pouya Gholizadeh - University of Nebraska- Lincoln

Sogand Hasanzadeh - University of Nebraska- Lincoln

Erik Bruening - University of Nebraska- Lincoln

Brett Farquhar - University of Nebraska- Lincoln


Hazards Addressed:

Availability

Coral Sales Co.
To obtain information, visit http://www.coralsales.com/ or contact (503)-655-6351

PSS Innovations
To obtain information, visit http://pss-innovations.com/ or contact (888)-653-6800

TrafFix Devices, Inc.
To obtain information, visit https://www.traffixdevices.com/ or contact (949)-361-5663

Road-Tech Safety Sevices, Inc.
To obtain information, visit https://www.road-tech.com/ or contact (530)-672-0222

Transportation Supply
To obtain information, visit http://www.trans-supply.com/default.aspx or contact (866)-930-4604

Street Smart Rental
To obtain information, visit https://www.streetsmartrental.com or contact (866)-930-4604

Return on Investment

To calculate the return on investment (ROI) for your specific application, please visit our Return on Investment Calculator. While a specific ROI example has not been developed for this particular solution, the ROI Calculator provides a useful tool and guidance on how to generate your own on investment analysis.