Post on 09-Nov-2021
M O N T H L Y D E L M A R V A M I S S U T I L I T YM E M B E R M E E T I N G
M A R C H 2 0 , 2 0 1 4
Temporary Traffic Control for Highway Work Zones
P R E S E N T E D B Y :A d a m W e i s e r , P . E . P T O ES a f e t y P r o g r a m s M a n a g e rD e l a w a r e D e p a r t m e n t o f T r a n s p o r t a t i o n
Agenda
Background Information Introduction to Temporary Traffic Control (TTC) Planning Considerations TTC Elements TTC Operations Contact Information Questions
Background Information
Number of highway work zones continue to increase Capital projects Maintenance projects Utility and developer projects
Increasing congestion in and around work zones Increased amount of night work as a result
Delaware Strategic Highway Safety Plan Designing Safer Work Zones – Secondary
Emphasis Area #4
Fatal Work Zone Crashes
Source: NHTSA (2013 national data not yet available)
0
100
200
300
400
500
600
700
800
900
2006 2007 2008 2009 2010 2011 2012 2013
National
Delaware
Delaware Work Zone Crashes
Source: Delaware State Police
2006 - 2013
0
50
100
150
200
250
300
350
400
2006 2007 2008 2009 2010 2011 2012 2013
Property Damage Only
Personal Injury
Fatal
Delaware Work Zone Crashes
Source: Delaware State Police
2006 - 2013
0
100
200
300
400
500
600
700
800
900
1000
Rear‐End Head‐On Sideswipe Rear to Side Rear to Rear Other Unknown SingleVehicle
Angle
Manner of Impact
Introduction to TTC
Temporary Traffic Control (TTC) Normal function of roadway, or a private road open to public travel,
is suspended or disrupted, TTC planning provides for Continuity of movements for all users Access to property and utilities
TTC shall be provided for all road users Motorists Bicyclists Pedestrians, including those with disabilities
Types of Work Zones Highway construction Utility work (installation, repair, relocation) Maintenance operations Traffic incidents (crashes)
Design and Construction Guidance
Delaware Manual on Uniform Traffic Control Devices (MUTCD) Part 6 – Temporary Traffic Control
DelDOT’s Work Zone Safety & Mobility Guidelines
ATTSA Quality Guidelines Brochure
AASHTO Roadside Design Guide AASHTO Manual for Assessing
Safety Hardware (MASH)
Permits
Permit required for any work that impacts DelDOT right-of-way
Permits obtained through the DelDOT Public Works Section New Castle County – (302) 326-4679 Kent County – (302) 760-2433 Sussex County – (302) 853-1340
Types of Permits Entrance permits (subdivision entrances) Utility permits (self explanatory) Safety permits (all other types of work)
Planning Considerations
Work Duration Long-term stationary – occupies location more than 3 days Intermediate-term stationary – occupies location more than
one daylight period up to 3 days, or nighttime work lasting more than 1 hour
Short-term stationary – occupies location more than 1 hour within single daylight period
Short duration – occupies location up to1 hour
Mobile – work that moves intermittently or continuously
Planning Considerations
Mobility Impacts Capacity reduction due to work zone alone
Can occur without impacting travel lanes Rubber necking
Capacity reduction due to loss of travel lane(s) Increased and even excessive queuing Increased travel time due to low speed
and queuing Increased delay, especially when
impacting signalized intersections Impacts due to detours
Increased travel time Increased fuel consumption
Mobility Impacts lead to increased Road User Costs
These are quantifiable impacts
Planning Considerations
Mobility Impacts All road users are impacted
Vehicular traffic Bicyclists Pedestrians, including
those with disabilities Impacts to emergency
response times Transit impacts
Work zone strategies should minimize these impacts
Planning Considerations
Safety Impacts Worker Safety
Exposure protection Use of barrier or other positive separation
between work space and traffic space High-visibility safety apparel Training Shadow vehicles with crash attenuators Alternative traffic control schemes Full or partial road closures
Law enforcement use Lighting Special devices Rumble strips Changeable message signs Intrusion warning devices
Planning Considerations
Traffic Safety Impacts Separation from workers Work vehicle ingress/egress
Give work vehicles space toaccelerate and decelerate away fromtraffic
Storage of equipment Equipment and material are
considered fixed objects
Pavement edge drop-offs Speed limits
Components of Highway Works Zones
Four main component areas Advance warning area Transition area Activity Area
Buffer Space Work Space
Termination Area
Components of Highway Work Zones
Advance Warning Area Informs road users of what
to expect Can consist of a
single sign or vehicle with flashing beacons, or a series of TTC signs in advance of a TTC activity area
Distance of advance warning area varies depending upon type of road and duration of work
Components of Highway Work Zones
Transition Area Section of highway where road users are directed
out of their normal path Tapers are generally used
• Merging taper• Lane shift taper
• Shoulder taper
Components of Highway Work Zones
Tapers
60
2WSL WSL
S ≤ 40 MPH S > 40 MPHL = taper length in feetW = width of offset in feet*S = posted speed limit or off-peak 85th percentile speed
prior to work starting
Type of Taper Taper Length
Merging Taper at least L
Shifting Taper 0.5 L to L*
Shoulder Taper at least 0.33 L
One-Lane, Two-Way Traffic Taper 50 feet minimum, 100 feet maximum
Downstream Taper 50 feet minimum, 100 feet maximum
Components of Highway Work Zones
Types of Tapers and Buffer Spaces
Source: 2011 Delaware MUTCD, Figure 6C-2
Components of Highway Work Zones
Activity Area Section of highway where the work takes place Comprised of three main components
Traffic Space Work Space Buffer Space
LongitudinalBuffer Space
Lateral Buffer Space
Components of Highway Work Zones
Types of Tapers and Buffer Spaces
Source: 2011 Delaware MUTCD, Figure 6C-2
TTC Devices
Signs Channelization Devices Cones Drums Barricades
Arrow Boards Truck Mounted Attenuators Flaggers Quality of TTC Devices
Signs
Sections 6F.02 – 6F.58 Warning signs most commonly used
Shall be diamond-shaped with a blacklegend and border or a fluorescent orangebackground
Sign placement Spacing based on speed of roadway Table 6C-1
Sign mounting Up to three days – mounted on
temporary sign stand 5-foot mounting height
(pavement to bottom of sign) Greater than three days –
permanently mounted on breakaway signposts 7-foot mounting height
Signs and stands not in use shall be removedfrom the roadway each day
Channelization Devices
Cones (Section 6F.64) Shall be orange in color Shall be a minimum of 28-inches
tall Shall not be used at night, except
for emergencies and plannedspecial events
Shall have two retroreflectivewhite bands (cones 28” – 36” inheight)
Drums (Section 6F.67) Shall be a minimum of 36” in
height and a minimum 18” in width Markings shall be alternating orange and white starting with orange
at the top. Fluorescent orange and white prismatic retroreflective sheeting Ballast shall not be placed on top of drum
Channelization Devices
Barricades (Section 6F.68) Type I not permitted on
state-maintained roadways Type II shall only be used for
pedestrian channelization alongtemporary pedestrian paths. They shall not be used to closea roadway, sidewalk or crosswalk
Type III barricades permitted for useto close roadways, sidewalks and/orcrosswalks For full road closures, barricades shall
extend the entire width fromcurb-to-curb or edge of pavementto edge of pavement
Lights are not required and should notbe used at the tops of Type III barricades
Arrow Boards
Section 6F.61 Flashing arrow or flashing caution
operating modes should be used on state-maintained roadways Prefer not to use sequential modes
Shoulder work – use the flashing caution mode
Lane closure – use the flashing arrow mode
Do not use for lane shifts A One-Direction Large Arrow (W1-
6) sign shall be centered below and attached to the bottom of all trailer mounted arrow boards
Remove from roadway when not in use
Truck Mounted Attenuators
Section 6F.86 Energy-absorbing device attached to the rear of shadow
vehicles (truck or trailer) Designed to absorb the impact of an
errant vehicle Protects the workers on the roadway
Shall be used on roadways with aposted speed limit greater than 40miles per hour Long-term stationary Intermediate-term stationary Short-term Mobile operations
Must be crash tested in accordance with NCHRP 350/MASH Roll-ahead distance
Other Devices
Flaggers (Section 6E) Shall be certified by a DelDOT-recognized flagger certification program
Currently ATSSA certification Training available through T2 center
or Delaware Safety Council Shall not use unapproved electronic
devices No cell phones, no texting, no MP3
players, etc. Shall wear a Class III safety vest
Light plants Used at night for all flagger stations
Vehicle lighting All vehicles in work zone required to have a large rotating amber beacon
or strobe lights Must be seen 360-degrees around the vehicle Visible for 3,000 feet under normal atmospheric conditions
High Visibility Safety Apparel
Covered in Section 6D.03 of Delaware MUTCD
Minimum requirement ANSI/ISEA 107-2004,
Performance Class 2 high-visibility safety apparel for all workers, except flaggers, within the right-of-way
Flaggers are required to wear ANSI/ISEA, Performance Class 3 high-visibility safety apparel
Regardless of activity, high-visibility safety apparel is required. Don’t step out of your vehicle without it!
Quality of TTC Devices
The use of clean, highly reflective and legible devices promotes work zone safety
DelDOT adopted the ATSSA Quality Guidelines brochure as it’s guidelines for the quality of TTC devices
Any device not meeting the marginal criteria shall be removed from the roadway
Typical Applications
Most commonly used Typical Applications TA-3 – Shoulder work on a Two-Lane Road TA-3A – Shoulder work on a Multilane
Divided Highway TA-10 – Lane closure on a Two-Lane Road TA-33 – Lane closure on a Multilane
Divided Highway TA-37 – Double lane closure on a
Multilane Divided Highway Approved permit will identify the
proper TA to be used If a TA does not meet the needs of the
work area, TTC plans must be developed and approved
Pedestrian Accommodations
If the TTC zone affects the movement of pedestrians, adequate pedestrian access and walkways shall be provided.
It an accessible path is affected, a temporary path with similar accessible features but be provided
Do not park vehicles on sidewalks
If sidewalks need to be closed, utilize TA-28 or TA-29 to accommodate pedestrians
Aerial Work
Interim Guidance issued on November 13, 2012 Work being performed over a roadway open to traffic Travel lane and/or shoulder directly below work area shall be closed Use appropriate TTC for
location, duration and typeof work being performed
Emergency work thatcreates an unsafesituation for the travelingpublic Lanes can remain open until
imminent safety hazard is dealt with Rules above apply thereafter to complete repairs
Setting and Removing TTC
Installation of TTC Install advance warning signs, starting with the first sign and ending
with the END ROAD WORK sign Install shoulder taper Install arrow board on shoulder Install lane closure taper in direction of travel Install channelization devices for buffer and activity areas Install termination taper
Removal of TTC Remove devices in the reverse direction starting with the termination
area Remove arrow board and shoulder closure taper Remove signs in the direction of travel starting with the first sign and
ending with the END ROAD WORK sign Always review the TTC after initial setup and then periodically
during duration of work Use TMAs as appropriate
Safety Section Contact Information
Wayne Hamilton, North District Safety OfficerO: (302) 326-4495E: Wayne.Hamilton@state.de.us
Jim King, Canal District Safety Officer, ActingO: (302) 659-4071E: James.King@state.de.us
Jim King, Central District Safety OfficerO: (302) 659-4071E: John.Subda@state.de.us
Dan Thompson, South District Safety OfficerO: (302) 853-1339E: Dan.Thompson@state.de.us
Gerald Nagyiski, Jr.Chief Safety OfficerO: (302) 659-4072E: Gerald.Nagyiski@state.de.us
Adam Weiser, P.E., PTOESafety Programs ManagerO: (302) 659-4073E: Adam.Weiser@state.de.us