ROADSIDE DESIGN GUIDE GLOSSARY
|LATEST UPDATE {GRADED A+}
Adjacent Grading - ✔✔Refers to the area on which the terminal is installed
and the area immediately behind it.
Advance Grading - ✔✔Refers to the area over which a vehicle may travel
before any contact with a barrier terminal is made.
Anchorage - ✔✔A device which anchors a flexible or semi-rigid barrier to
the ground so as to develop the barrier's tensile strength during an impact.
Anchorages differ from terminals in that they are not considered
crashworthy.
Area of Concern - ✔✔An object or roadside condition that may warrant
safety treatment.
Barricade - ✔✔A device which provides a visual indicator of a hazardous
location or the desired path a motorist should take. It is not intended to
contain or redirect an errant vehicle.
, Barrier - ✔✔A device which provides a physical limitation through which a
vehicle would not normally pass. It is intended to contain or redirect an
errant vehicle.
Bi-directional - ✔✔For the purposes of classifying crash cushions, bi-
directional describes the capability of a crash cushion to safely operate in
the median of a divided highway or on an undivided roadway, where it will
be exposed to impacts from two different direc tions of traffic. A bi-
directional crash cushion is also a uni-directional crash cushion. A crash
cushion is considered to be bi-directional when it has been qualified
through a reverse-direction crash test.
Breakaway - ✔✔A design feature which allows a device such as a sign,
luminaire, or traffic signal support to yield or separate upon im pact. The
release mechanism may be a slip plane, plastic hinges, fracture elements,
or a combination of these.
Bridge Railing - ✔✔A longitudinal barrier whose primary function is to
prevent an errant vehicle from going over the side of the bridge structure.
Clearance - ✔✔Lateral distance from edge of traveled way to a roadside
object or feature.
|LATEST UPDATE {GRADED A+}
Adjacent Grading - ✔✔Refers to the area on which the terminal is installed
and the area immediately behind it.
Advance Grading - ✔✔Refers to the area over which a vehicle may travel
before any contact with a barrier terminal is made.
Anchorage - ✔✔A device which anchors a flexible or semi-rigid barrier to
the ground so as to develop the barrier's tensile strength during an impact.
Anchorages differ from terminals in that they are not considered
crashworthy.
Area of Concern - ✔✔An object or roadside condition that may warrant
safety treatment.
Barricade - ✔✔A device which provides a visual indicator of a hazardous
location or the desired path a motorist should take. It is not intended to
contain or redirect an errant vehicle.
, Barrier - ✔✔A device which provides a physical limitation through which a
vehicle would not normally pass. It is intended to contain or redirect an
errant vehicle.
Bi-directional - ✔✔For the purposes of classifying crash cushions, bi-
directional describes the capability of a crash cushion to safely operate in
the median of a divided highway or on an undivided roadway, where it will
be exposed to impacts from two different direc tions of traffic. A bi-
directional crash cushion is also a uni-directional crash cushion. A crash
cushion is considered to be bi-directional when it has been qualified
through a reverse-direction crash test.
Breakaway - ✔✔A design feature which allows a device such as a sign,
luminaire, or traffic signal support to yield or separate upon im pact. The
release mechanism may be a slip plane, plastic hinges, fracture elements,
or a combination of these.
Bridge Railing - ✔✔A longitudinal barrier whose primary function is to
prevent an errant vehicle from going over the side of the bridge structure.
Clearance - ✔✔Lateral distance from edge of traveled way to a roadside
object or feature.
