Product and Installation Manual: Sentry Barrier TL-4 ThrieBeam System
ACP
| September 2020 |
Page
10
New South Wales
Sydney
02 8708 4400
Victoria
Melbourne
02 8708 4400
Queensland
Brisbane
07 3442 6200
Western Australia
Perth
02 9772 4172
Horizontal and Vertical Curves
The
Sentry Barrier TL-4 ThrieBeam System
can accommodate both horizontally and vertically
curved guardrail panels if required by site conditions. For radii less than 25m the system must be
anchored with an approved intermediate anchor or terminal end. Please refer to approved details of
the local Road Controlling Authority where necessary.
Concave Corner Convex Corner
Undulating Ground Conditions
Site specific grading may be necessary to ensure that there are no
‘humps’ or ‘hollows’ that may
significantly alter the impacting vehicles stability or substantially alter the ThrieBeam heights in
relation to the ground. The
Sentry Barrier TL-4 ThrieBeam System
is required to be installed level
and centred on the barrier line as stated in the Installation Procedure.
Care must be taken to ensure all posts in the
Sentry Barrier TL-4 ThrieBeam System
are installed
to the correct height, alignment and orientation. It is strongly recommended that smoothing of
uneven ground conditions be completed along the length of the
Sentry Barrier TL-4 ThrieBeam
System
.
Clear Zone / Hazard Free Zone
Clear Zones are areas adjacent to traffic lanes that provide errant vehicles the opportunity to slow
down or recover. The clear zone must be kept clear from roadside features that could be hazardous
to errant vehicles, such as but not limited to trees, poles and culverts. Although it is desirable to
maximize the available clear zone, please refer to your local Road Controlling Authority for
confirmation of the minimum width requirements.
Terminal Ends
The
Sentry Barrier TL-4 ThrieBeam System
is designed to be compatible with a range of guardrail
terminals ends or crash cushions available, in accordance with designated transition details. It is
recommended that
MAX-TENSION
terminal ends be used with the
Sentry Barrier TL-4 ThrieBeam
System
for optimal performance. The
X-TENSION 350
terminal ends can also be utilised if required.
Refer to the
Appendices
section for detailed drawings.
The purpose of the guardrail terminals ends, or crash cushions is to provide a soft impact and to
prevent the end rail from spearing or impacting the errant vehicle. The terminal ends and crash
cushions also provide tensile and deflection strength necessary to ensure the errant vehicle is
redirected for the length-of-need required.
