BOLLARD TESTING |
Testing the flexibility and safety of bollards has become a crucial
part of the process when upgrading roadways in the US
Words | Peter Speer, Pexco, USA
are essential on
express lanes Have you ever wondered
Below: Pexco City
Posts line the I-77
in Charlotte, North
Carolina. State-ofthe
168 Intertraffic World | Annual Showcase 2020
art bollards
why the United States is
home to the most durable,
flexible bollards in the
world, leading to numerous managed
and express lane installations using
these products? This did not happen
by accident.
Testing of flexible delineator
posts in the USA is conducted by
the National Transportation Product
Evaluation Program (NTPEP)
and overseen by the American
Association of State Highway and
Transportation Officials (AASHTO),
with the findings revealed in a
structured document.
The process wasn’t always this
well organized. The protocol for
testing flexible posts in the USA has
evolved considerably over the past
30 years. For a long time, individual
state transportation agencies
conducted their own evaluation of
flexible posts. They had their own
process – sometimes their own test
facilities – and many times differing
procedures. A product might pass in
one state but fail in another.
Thirteen southern US states
comprising the Southeast Association
of State Highway and Transportation
Officials (SASHTO) were elected
in 1987 to combine their separate
programs into a single entity.
Technical committees that included
manufacturers were formed to
collaborate on acceptable, uniform
test methods. This was the first
move towards standardization
in the United States.
NTPEP was established in 1994
as a technical services program
reporting to AASHTO’s standing
committee on highways. NTPEP
combined the resources of all 52
AASHTO member states to evaluate
materials of common interest for
use on highways. The goal of the
program was to provide cost-effective
product evaluations for the states by
eliminating duplication of effort.
Testing approach
A testing protocol was developed
by NTPEP’s temporary traffic
control device (TTCD) committee
for evaluation of both ground and
surface-mounted posts, with the
lead state being Tennessee. The
protocol for surface-mount posts
consisted of acquiring ten samples
from a manufacturer, selected
by an employee of the local state
DOT. Those samples were then
sent to Tennessee for both field
and laboratory testing. Laboratory
testing was conducted on two of the
posts to measure physical properties
and resistance to weathering.
The NTPEP protocol for impact
testing was to subject eight posts to
ten impacts at 90km/h (55mph) by
a standard passenger vehicle. The test
vehicle impacted two rows of posts
so that one row of four posts received
bumper impacts and the other row
of four received direct wheel-over
impacts. Five impacts were
The beat goes on