ROAD SAFETY AUDIT
TRUCK ROLLOVER CRASHES
I-295/I-95 Interchange
City of Attleboro
August 31, 2011
Prepared For:
MassDOT Highway Division
Prepared By:
BETA Group, Inc.
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Table of Contents
Project Data .................................................................................................................................1
Background .................................................................................................................................2
Project Description .....................................................................................................................2
Audit Observations .....................................................................................................................6
Potential Safety Enhancements .................................................................................................7
Summary of Road Safety Audit...............................................................................................11
List of Appendices
Appendix A.
Appendix B.
Appendix C.
Appendix D.
RSA Meeting Agenda
RSA Audit Team Contact List
Detailed Crash Data
Traffic Volume Data
List of Figures
Figure 1.
Location Map ......................................................................................................................... 3
List of Tables
Table 1.
Table 2.
Table 3.
Participating Audit Team Members ....................................................................................... 1
Estimated Time Frame and Costs Breakdown ....................................................................... 7
Potential Safety Enhancement Summary ............................................................................. 12
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Project Data
A Road Safety Audit for Truck Rollover Crashes at the interchange of Interstate 295 (I-295) and Interstate
95 (I-95) in Attleboro was held on July 20, 2011 at the South Attleboro Fire Station in South Attleboro,
MA. As indicated in Table 1, the audit team consisted of representatives from Federal, State, Regional
and Local agencies and included a cross-section of engineering, planning, operations, safety, enforcement
and emergency response expertise.
Table 1. Participating Audit Team Members
Audit Team Member
Agency/Affiliation
Bonnie Polin
MassDOT Highway Division – Safety Section
Lisa Schletzbaum
MassDOT Highway Division – Safety Section
Robert Gregory
MassDOT Highway Division District 5
Edward Feeney
MassDOT Highway Division District 5
Neil Boudreau
MassDOT Highway Division – State Traffic Engineer
Paul Powell
Massachusetts State Police
Scott LaChance
Attleboro Fire Department – Fire Chief
Andrew Klane
Massachusetts State Police – CARS (Collision Analysis &
Reconstruction Section)
Jeff Stuart
Massachusetts State Police – Foxboro
Thomas Fitzgerald
Massachusetts State Police – CVES (Commercial Vehicle
Enforcement Section)
Matthew Poirier
FMCSA – USDOT
Christopher Cardaci
SRPEDD - Transportation
Thomas Burnett
MassDOT Highway Division – Safety Section
Jeff Young
MassDOT Highway Division – Safety Section
David Phaneuf
MassDOT Highway Division – Design Section
Alolade Campbell
MassDOT Highway Division District 5
Greg Lucas
BETA Group, Inc.
Christine Keches
BETA Group, Inc.
Page 1
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Background
The Federal Highway Administration defines a Road Safety Audit (RSA) as the formal safety
examination of an existing or future road or intersection by an independent, multidisciplinary team. The
purpose of an RSA is to identify potential safety issues and possible opportunities for safety
improvements considering all roadway users. A Road Safety Audit was scheduled for the I-295 and I-95
interchange because it has been identified as the highest truck rollover crash location in the State. The
audit focused on the ramp from I-95 Southbound to I-295 Southbound and the ramp from I-295
Northbound to I-95 Northbound, the ramps with the highest occurrence of rollover crashes at the
interchange. The purpose of the RSA is to identify both short and long term safety improvements that can
be implemented to reduce crashes at the interchange.
Project Description
The interchange of Interstates 95 and 295, shown in Figure 1, is located in the northern section of
Attleboro and is adjacent to the North Attleborough Town Line. I-295 terminates at I-95, but was
originally intended to extend east of I-95; as such, the ramp layout at the interchange is similar to that of a
full cloverleaf interchange. The study ramp from I-295 Northbound to I-95 Northbound and the ramp
from I-95 Northbound to I-295 Southbound are loop ramps, while the study ramp from I-95 Southbound
to I-295 Southbound and the ramp from I-295 Northbound to I-95 Southbound are composed of
compound and reverse curves. A closer look at Figure 1 indicates that the ramps to and from I-95
Southbound were designed to accommodate inner loop ramps to the unbuilt extension of I-295 eastward.
I-295 is approximately 27 miles in length and forms a western bypass of Providence, RI, extending from
Attleboro to Warwick, RI. Truck traffic on I-295 has increased due to a weight restriction on an I-95
bridge in Pawtucket, RI. The bridge is restricted to vehicles under 18 tons, and warning signs before I-295
in Massachusetts direct trucks to use I-295 as a bypass. It was suggested during the audit that there has
been a larger increase in southbound truck traffic on I-295 than northbound because northbound trucks
are using the local detour in Pawtucket, while the local detour southbound is less convenient. Complete
information regarding the Pawtucket River Bridge detour can be found at
http://www.dot.state.ri.us/travelri/bridge550.asp.
The increase in southbound truck traffic on I-295 results in an increase in truck traffic on the ramp from I95 Southbound to I-295. It was noted that the frequence of rollover crashes on the I-95 Southbound to I295 ramp has increased since the implementation of the detour, but that the majority of crashes are
occurring with operators who are familiar with the ramp. The I-295 to I-95 Northbound ramp has a
history of rollover crashes predating the weight restriction detour.
Truck rollover crash data for the interchange were provided by the Massachusetts State Police for the
years 2008 through 2010. The diagram included in the Appendix shows six rollover crashes on the ramp
from I-95 Southbound to I-295, and five rollover crashes on the ramp from I-295 Northbound to I-95
Northbound. There were two other known truck rollovers during the study period for which crash data
was unavailable.
Page 2
ATTLEBORO
5N
B
I-9
I- 9
5S
B
³
NORTH
ATTLEBOROUGH
STUDY AREA RAMP:
I-95 SB TO I-295 SB
5N
B
STUDY AREA RAMP:
I-295 NB TO I-95 NB
I- 9
I-9
5
SB
I-295
0
250
500
1,000
Feet
Route I-95 / Route I-295 Ramps
315 Norwood Park South
Norwood, MA 02062
781.255.1982
BETA@BETA-inc.com
ROAD SAFETY AUDIT
Figure 1
ATTLEBORO, MA
Location Map
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
The diagram also shows one crash on the ramp from I-295 Northbound to I-95 Southbound, which was
not included in the audit study area. A closer analysis of the six crashes on the ramp from I-95
Southbound to I-295 reveals that one occurred on the first superelevated curve on the ramp, while five
occurred on the curve where the ramp transitions into a merge with I-295. It was suggested that the
rollover crashes near the end of the ramp may be a result of drivers accelerating to merge onto the I-295
mainline while the trailer is still navigating the curve. This possible increase in speed and shift in load
may be causing the trailer wheels to lift and subsequently cause a rollover. The ramp from I-295 to I-95
Northbound has two tight radii curves as part of the compound curve loop geometry. These two curves
each experienced two crashes. The two crashes in the first curve may be the result of drivers entering the
curve at an unsafe speed, while the two towards the end of the ramp may be the result of a driver
accelerating to begin merging into traffic on I-95.
Signs warning of both the curve geometry and the rollover potential are
present on both ramps. The ramp from I-95 Southbound to I-295 has an
MUTCD standard W1-13 Truck Rollover warning sign in the ramp
deceleration area on I-95, an advisory exist speed sign posted at 30 mph, a
pair of W1-13 signs in advance of the curve at the end of the ramp, and W18 chevron arrows on the curve. The ramp from I-295 Northbound to I-95
Northbound has the usable lane width restricted by gore markings from both
edges of pavement and has W1-13 signs posted on both sides of the roadway
in advance of the loop curve. Both signs have a
25 MPH advisory plaque, and the left side sign
has four warning beacons flashing in a wig-wag
pattern. An overhead guide sign is provided
which graphically indicates the loop geometry of
the ramp. Two more paired sets of W1-13 signs
with 25 MPH advisory plaques are provided
before the beginning of the loop. W1-8 chevron
arrows and three lighted arrow boards are
positioned at the beginning of the curve transition
where the highway extension would have
continued. Concrete barriers are provided along
the left side of the ramp from the I-95 overpass
I-95 Southbound at Exit 4 (I-295)
through the first curve of the compound loop.
Advance signage and ramp signage for the I-295
to I-95 Northbound ramp were recently updated
to match signage that was installed at the I-95
Northbound ramp at Route 128 in Canton, which
has similar geometry. It was noted that the
frequence of rollover crashes has since been
reduced at that location.
Delineator posts are provided along the edges of
both study ramps, although many are missing.
I-295 End at I-95 Northbound on-ramp
Page 4
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Automatic Traffic Recorder (ATR) data collected in March of 2011 were made available to audit
participants. The data show that the ramp from I-95 Southbound to I-295 carries 14,400 vehicles per day
(vpd), and has a truck percentage of 10% daily and 4% in the peak hour. The ramp from I-295
Northbound to I-95 Northbound carries 14,100 vpd and has a truck percentage of 10% daily and 4% in
the peak hour. The overall average daily traffic (ADT) on I-95 north of I-295 is 105,300 vpd with a truck
percentage of 6% daily and 3% in the peak hour, while the ADT on I-95 south of I-295 is 82,400 vpd with
a truck percentage of 5% daily and 4% in the peak hour.
Page 5
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Audit Observations
Following a brief introduction to the RSA process and a summary of crash and traffic volume
information, the audit participants were asked to discuss safety issues and other factors that lead to the
occurrence of rollover crashes at the I-95/I-295 interchange. Audit participants also viewed a video
recording of the two study ramps and noted safety issues and contributing factors both during and
following the video.
Design Speed – It was noted that the 1967 Design Plans show a 240’ radius on the ramp from I-95
Southbound to I-295 and a 227’ radius on the I-295 to I-95 Northbound ramp. A review of other
Interstate to Interstate interchanges revealed similar geometry. This led into a more detailed
discussion of the design standards at the time the interchange was designed and how the size and
allowable weight of vehicles have changed. For example, it was noted that Massachusetts has an
exception to the federal standard, which sets a maximum gross vehicle weight (GVW) of 80,000
pounds, and will allow a vehicle with a GVW up to 99,000 pounds. It was suggested that this
increased maximum allowable vehicle should require a change in design methodology or a reduction
in the allowable speed.
Vehicle Speed – It was suggested that some trucks are traveling at or in excess of the 30 MPH
advisory speed established for the ramp from I-95 Southbound to I-295.
Acceleration and Load Shifting– The ramp from I-95 Southbound to I-295 has experienced more
crashes where the ramp begins to merge with the I-295 mainline. It was suggested that driver
acceleration before the trailer reaches the end of the curve may be causing rollovers as this would
cause a subsequent shifting of the load in the trailer. It was also noted that the uphill grade of the
ramp causes drivers to accelerate in order to get upgrade. An audit member noted that some of the
rollever crashes involved empty trucks.
Pavement Markings – Pavement markings are generally in good condition. Modifications to
pavement markings may be used to change driver perception when navigating the ramps.
Ramp Delineation – In-pavement reflectors are not provided along either study ramp. Reflectors
would help delineate the ramp for nighttime travel. Delineator posts are installed, but many are
damaged or missing. It was noted that several crashes occurred at night, although specific data were
not provided.
Queueing During Peak Periods – It was suggested that the ramp from I-95 Southbound to I-295
experiences queueing delays, especially during the afternoon peak period. A closer analysis of the
crash history revealed that rollover crashes are not occurring during the peak periods, likely due to the
reduced vehicle speeds brought about by traffic congestion. Queueing is therefore not a factor in truck
rollover crashes and was not further discussed during the audit.
Signage – It was suggested that existing signage does note a rollover warning but may not be
adequate based on the continued frequency of rollover crashes.
Page 6
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Pavement Condition – Worn pavement can have a lower friction coefficient which can be related to
an increased risk of rollover crashes. Subsequent to the meeting, contract records were reviewed to
determine that the ramps were resurfaced within the last three years. The pavement appears to be in
good condition.
Potential Safety Enhancements
Audit participants identified safety issues and also recommended potential improvements to address these
issues. These improvements are intended to reduce the number of rollover crashes, reduce the severity of
all crashes and increase the overall safety of the I-295/I-95 interchange. Specific recommendations are
discussed in detail in this section and summarized in Table 3. Each improvement considered has been
categorized as short-term, mid-term, or long-term based on the definitions shown in Table 2.
Additionally, a cost category has been assigned to each improvement based on the parameters set forth in
Table 2.
Table 2. Estimated Time Frame and Costs Breakdown
Time Frame
Short-term
<1 year
Costs
Low
Mid-term
1–3 years
Medium
Long-term
>3 years
High
<$10,000
$10,000–$50,000
>$50,000
Re-evaluate design speed based on maximum truck capacity allowed. MassDOT minimum design
standards are based on FHWA standards, which are based on a truck with a maximum GVW of
80,000 pounds. Massachusetts has an exception which allows trucks with a GVW up to 99,000
pounds. The posted speed should be based on the theoretical capacity of the existing ramp based on
the higher weight trucks. This is a short-term improvement that requires study.
Calculate speed advisory and potential for rollover based on actual truck data. This improvement was
discussed in tandem with and is related to the improvement discussed above. This improvement
would require collecting data from trucks, possibly at the point of origin. This data could then be used
along with the ramp geometry and pavement friction data to calculate the theoretical speed at which a
truck would begin to tip and set the speed advisory below that threshold. This is a short-term
improvement that requires study.
Modify pavement markings to influence driver behavior. This improvement involves modifying the
pavement markings on both study ramps. Acceleration at the end of the ramp from I-95 Southbound
to I-295 may be a factor in the crash history of the ramp. The geometry of the ramp combined with
the visibility of the open, typically uncongested pavement on I-295 may give the driver the perception
that they have exited the ramp and can accelerate to highway speed on I-295. Modifying the
pavement markings to extend the curve could make the driver feel as if they are still traversing the
curve, which, in turn, may reduce vehicle speed and acceleration. It was also suggested that the
pavement markings be modified on I-295 Northbound entering the loop ramp towards I-95
Northbound. Gore markings would be widened to reduce the lane width, potentially reducing speeds
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
as drivers enter the curve. This is a short-term, medium cost improvement that includes removing
conflicting existing markings.
Plant trees and/or shrubs to provide a natural barrier between the I-95 Southbound to I-295 ramp and
the I-295 mainline. As previously discussed, a driver may perceive that they are entering the I-295
mainline prematurely and accelerate while still traversing the curve. It was suggested that plantings in
the ramp gore area would better define the ramp area and reduce the driver’s view of the I-295
mainline, which could eliminate the perception that they are at an appropriate point to accelerate to
highway speed. This is a short-term, medium cost improvement. Proposed plantings should not
encroach on clear zone standards set forth by MassDOT’s Project Development and Design Guide
and AASHTO’s Roadside Design Guide.
Install in-pavement reflectors along all ramps at the interchange. MassDOT has installed in-pavement
reflectors, also known as raised pavement markers, along many miles of highway throughout the
Commonwealth. These reflectors should be installed along all four ramps at the I-295/I-95
interchange to increase visibility and awareness of the ramp geometry at night. This is a short-term,
medium cost improvement.
Replace missing delineator posts. Delineator posts are present along both study ramps, but many are
missing. All damaged or missing delineators should be replaced along all interchange to increase
visibility and awareness. This is a short-term, low cost improvement.
Consider in-pavement lights. It was suggested that in-pavement lights could be added to increase
awareness of the curve geometry. MassDOT personnel noted that last year locations were being
sought to install solar powered in-pavement lights on a trial basis. It is recommended that the ramp
from I-95 Southbound to I-295 be considered as a trial location for this product. This is a short-term,
low cost improvement.
Increase awareness of ramp advisory speed. A number of methods were suggested to increase
awareness of ramp advisory speed and driver speeds and are discussed in detail below. All
improvements discussed could be implemented with the existing ramp advisory speed, or could be
modified if a reduction in the advisory speed is justified.
o Install intelligent speed board with picture taking capability. Technological advances in
intelligent transportation systems have brought about a number of devices which record
data when prompted by a specific control input. It was suggested that a device could
measure actual speeds, keep a record of speed data, and take a picture when a vehicle is
above a predetermined speed. This could help determine the speed at which a vehicle is
prone to rollover on the study ramps. This is a short-term, medium cost improvement.
o Modify speed advisory signage to include a truck speed advisory. The existing ramp
advisory exit speed sign warning of a 30 MPH speed has a black legend on a yellow
background following MUTCD standards. It was noted that a yellow advisory speed sign
does not hold regulatory weight and that speeding tickets based on ramp or exit advisory
speed signs are commonly overturned. It was also noted that speed limit signs can only be
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
posted where a special speed regulation has been established, and that a black on white
regulatory speed limit sign would not typically be installed on a highway ramp. It was
instead suggested that the existing sign be supplemented with a truck speed limit sign
establishing a 25 MPH advisory speed. This recommendation is not consistent with the
Manual on Uniform Traffic Control Devices (MUTCD), which states “when a Truck
Rollover (W1-13) sign (see Section 2C.13) is also installed for the ramp, the advisory exit
speed should be based on the truck advisory speed for the horizontal alignment using
recommended engineering practices.” As previously discussed, a study should be
undertaken to determine the appropriate advisory speed, and related signs should be
replaced if a lower advisory speed is determined to be appropriate. Replacement of signs
is a short-term, low cost improvement. Following the audit, MassDOT has ordered new
“EXIT 30 MPH” and “RAMP 30 MPH” advisory speed signs. The “EXIT 30 MPH”
sign is to be placed on the I-95 mainline prior to the overhead Exit 4 exit direction
sign, while the “RAMP 30 MPH” sign is to replace the existing ramp advisory sign.
Both signs are 60”x48”, which is larger than the existing ramp advisory sign.
o Add a supplemental speed panel to the W13-1 truck rollover signs. The ramp from I-295
to I-95 Northbound maintains 25 MPH advisory plaques mounted with W13-1 truck
rollover warning signs. Similar speed advisory panels should be added to the three W13-1
signs for the ramp from I-95 Southbound to I-295 once the calculated speed is
determined. The existing 25 mph advisory plaques should be revised if calculations show
that a new advisory speed is necessary. This is a short-term, low cost improvement. It
should be noted that MassDOT has ordered a new 48”x48” truck rollover sign with 30
MPH advisory speed panel to be placed on the left side of the I-95 Southbound to I-295
ramp after the Exit 4 exit gore sign.
o Install a dynamic speed advisory sign. It was suggested that the feedback provided by
these signs would help reduce speeds on the ramp for all vehicles, including trucks. This
could be implemented on both study ramps but was specifically discussed for the ramp
from I-95 Southbound to I-295. This is a short-term, medium cost improvement.
o Relocate “Speed Reader” signs to the interchange. MassDOT has existing “Speed
Reader” signs that could be relocated to the two study ramps as a short-term
improvement. The only cost of this improvement would be to transport the signs to the
interchange. It should be noted that these signs have been relocated to the interchange
following the audit meeting.
Consider larger chevron signs. The ramp from I-95 to Route 128 in Canton, which
has a similar geometry to the I-295 Northbound to I-95 Northbound ramp, utilizes
larger (42”x48”) W1-8 chevron signs. All chevron signs on the study ramps
should be replaced with this type of double chevron assembly. This is a shortterm, low cost improvement. It should be noted that MassDOT has ordered new
42”x48” chevron signs to be placed on the I-95 Southbound to I-295
Southbound ramp. These signs replace three chevron signs on the right-hand
Page 9
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
curve at the end of the ramp, and add chevron signs to the right-hand curve at the beginning of the
ramp and at the left-hand curve after the first tangent section of the ramp.
Provide “Extreme Rollover Hazard” supplemental
plaques with W13-1 truck rollover warning signs.
This was suggested as a potential improvement, but
is not recommended. Signs grading a potential
hazard are not recommended due to the potential
legal implications of an assumption of liability by
the owner. A subsequent comment from MassDOT
suggests considering “rollover hazard” advisory
signs on the I-95 mainline prior to the I-295
interchange. These panels would be similar to signs
currently in place on I-93 prior to the I-95/Rt. 128
interchange in Woburn, pictured at right. Rollover
advisory signs would be a short-term, low cost
improvement.
Consider replacing the existing exit gore signs with new signs that incorporate
the exit advisory speed. A comment received following the audit suggests that
the existing “EXIT 4” E5-1a gore signs be replaced with new signs that
include a yellow advisory banner showing the exit advisory speed, as shown at
right. This is a short-term, low cost improvement.
Use technology to transmit the potential rollover warning directly to drivers. It
was noted that GPS technology can warn drivers of potential hazards such as
construction, and that this system may be able to warn drivers in advance of the study ramps. It was
also noted a product called the CB Wizard has been used in other states to transmit a message over
the driver’s CB radio warning of work zones and other potential hazards. Each of these systems is a
short-term, low cost solution that would require further investigation of the specific technology
required.
Use high friction pavement on study ramps. It was noted that the state of Kansas has reported success
with high friction pavements in high rollover crash locations. This type of pavement should be
researched to determine its feasibility at the I-295/I-95 interchange. Increased pavement friction could
help keep the truck’s tires on the pavement and in turn prevent tipping and rollovers. This is a midterm, high cost improvement that requires additional study.
Re-align and reconstruct ramps. This is a long-term, high cost improvement. The existing ramp layout
was designed to accommodate a full cloverleaf geometry that is not needed because I-295 ends at I95. Realignment of the ramps would allow the use of smoother radii curves and eliminate the existing
geometry that contributes to the frequency of rollover crashes.
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Summary of Road Safety Audit
Table 3 summarizes potential recommendations discussed by the audit team. The recommendations are
categorized based on the potential safety payoff, as well as by time frame and cost. The safety payoff is a
qualitative judgment of the effectiveness of the potential safety improvements. The cost is a preliminary
order of magnitude estimate based on prior experience with roadway and safety improvements. Cost does
not include inflation or construction administration.
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Table 3.
Table 4. Potential Safety Enhancement Summary
Safety Issue
Safety Enhancement
Design Speed
Re-evaluate design speed based on maximum truck
capacity allowed (99,000 lb GVW)
Vehicle Speed
Vehicle Speed, Acceleration and
Load Shifting, Pavement Markings
Calculate advisory speed and potential for rollover
based on actual truck data.
Modify pavement markings to influence driver
behavior. This includes extending the curve markings
on the I-95 SB to I-295 ramp and increasing the gore
area on the I-295 to I-95 NB ramp.
Safety
Payoff
Responsibility
Time Frame
Cost
High
MSP Truck
Team/MassDOT
Short-term
TBD (Study)
High
MSP Truck
Team/MassDOT
Short-term
TBD (Study)
High
MassDOT
Short-term
$20,000
Medium
MassDOT
Short-term
$20,000
High
MassDOT
Short-term
$10,000
Medium
MassDOT
Short-term
$2,000
High
MassDOT
Short-term
TBD
Vehicle Speed, Acceleration and
Load Shifting
Plant trees and/or shrubs to provide a natural barrier
between the I-95 SB to I-295 ramp and the I-295
mainline.
Ramp Delineation
Install in-pavement reflectors (raised pavement
markers) along all four ramps at the interchange.
Ramp Delineation
Replace missing delineator posts.
Ramp Delineation
Consider in-pavement lights.
(This improvement assumes that lights are installed
on a trial basis and evaluated for effectiveness
following implementation.)
Vehicle Speed
Install intelligent speed board with picture taking
capability.
Medium
MassDOT
Short-term
$25,000
Vehicle Speed
Modify advisory speed signage. Replace exit speed
advisory signage pending results of design speed
study.
Medium
MassDOT
Short-term
$200
Vehicle Speed
Add advisory speed panel to the W13-1 truck rollover
signs on the I-95 SB to I-295 ramp. Revise signs on
the I-295 to I-95 NB ramp if needed.
Medium
MassDOT
Short-term
$500
Vehicle Speed
Install a dynamic speed limit sign providing feedback
to drivers.
High
MassDOT
Short-term
$15,000
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Table 3.
Table 4. Potential Safety Enhancement Summary
Safety
Payoff
Responsibility
Relocate Speed Reader signs to the interchange.
(This improvement has already been
implemented)
High
Vehicle Speed, Acceleration and
Load Shifting, Ramp Delineation
Replace chevron signs with larger 36‖x48‖ signs.
(Signs have already been ordered)
Vehicle Speed
Safety Issue
Safety Enhancement
Time Frame
Cost
Vehicle Speed
MassDOT
Short-term
$500
Medium
MassDOT
Short-term
$2,000
Install ―rollover hazard‖ advisory signs similar to
those installed on I-93 in Woburn.
Medium
MassDOT
Short-term
$4,000
Vehicle Speed
Replace existing ―EXIT 4‖ sign with a new sign
including a 30 MPH advisory speed banner.
Medium
MassDOT
Short-term
$2,000
Vehicle Speed
Use technology to transmit warnings to drivers using
GPS and CB radios.
High
MSP Truck
Team/MassDOT
Short-term
TBD
Pavement Condition
Use high friction pavement on study ramps.
High
MassDOT
Mid-term
$250,000
ALL
Re-align and reconstruct ramps.
High
MassDOT
Long-term
TBD
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Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Appendix A. RSA Meeting Agenda
Road Safety Audit
Attleboro – I-295/I-95 Interchange
Meeting Location: South Attleboro Fire Station
1476 West Street, South Attleboro
Wednesday, July 20, 2011
1:00PM – 3:00 PM
Type of meeting:
Road Safety Audit for Truck Rollover Crashes
Attendees:
Invited Participants to Comprise a Multidisciplinary Team
Please bring:
Thoughts and Enthusiasm!!
1:00 PM
Welcome and Introductions
1:15 PM
Review of Site Specific Material
• Crash Locations
• Ramp Video
2:00 PM
Visit the Site
• Drive to/thru the I-95 South to I-295 South Ramp and the I-295 North to I-95
North Ramp
• As a group, identify areas for improvement
2:30 PM
Completion of RSA
• Finalize discussion on all areas for improvement
• Discuss potential improvements with pros and cons and record possible
countermeasures
3:00 PM
Adjourn for the Day – but the RSA has not ended
Instructions for Participants:
• Before attending the RSA on July 20th, participants are encouraged to drive
through the ramps and consider roadway safety elements in relation to truck
rollovers.
• All participants will be actively involved in the process throughout. Participants
are encouraged to come with thoughts and ideas, but are reminded that the
synergy that develops and respect for others’ opinions are key elements to the
success of the overall RSA process.
• After the RSA meeting, participants will be asked to comment and respond to the
document materials to assure it is reflective of the RSA completed by the
multidisciplinary team.
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Appendix B. RSA Audit Team Contact List
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Appendix C. Detailed Crash Data
Road Safety Audit –Truck Rollover Crashes—I-295/I-95 Interchange—Attleboro, MA
Prepared by BETA Group, Inc.
Appendix D. Traffic Volume Data
I-95 north of Exit 4 (I-295)
2011 actual ADT = 105,300
2031 forecast ADT = 112,600
Truck Percentage: Tph = 3%, Tad = 6%
I-95 south of Exit 4 (I-295)
2011 actual ADT = 82,400
2031 forecast ADT = 87,100
Truck Percentage: Tph = 4%, Tad = 5%
I-295 Northbound Ramps:
Ramp to I-95 Northbound
2011 actual ADT = 14,100
2031 forecast ADT = 15,100
Truck Percentage: Tph = 4%, Tad = 10%
Ramp to I-95 Southbound
2011 actual ADT = 3,700
2031 forecast ADT = 4,000
Truck Percentage: Tph = 4%, Tad = 10%
I-295 Southbound Ramps:
Ramp from I-95 Northbound
2011 actual ADT = 4,000
2031 forecast ADT = 4,300
Truck Percentage: Tph = 4%, Tad = 10%
Ramp from I-95 Southbound
2011 actual ADT = 14,400
2031 forecast ADT = 15,400
Truck Percentage: Tph = 4%, Tad = 10%