ENGINEERING YOUR SAFETY
WWW.HIGHWAYCARE.COM
Rev. C
–
10/18
©2018 Highway Care Limited. All Rights Reserved.
Page
41
of
61
Expansion Joints
Expansion joints are not required on long runs
of barrier on normal carriageways.
Where expansion joints exist in the road
surface, such as at the edges of a bridge deck,
these should be mirrored in the BG800. If the
barrier is anchored either side of a bridge i.e.
not on the bridge structure but into the ground
either side of the structure, then there is no
need for expansion joints in the BG800.
Expansion within the system is catered for by
replacing the standard coupling plates found in
the connection between two 6m elements with
special plates which have elongated slots
enabling movement of the system under
temperature fluctuations. These units should be
pre-installed and correctly located and
identified on the load for speed of installation. If
this is not possible however, this process can be
performed on site.
For sites where the expansion of the ground
that the BG800 is to be anchored to is a concern
there is a special section of BG800 called a
Variable Length Section which could be utilised.
This requires T-Top sections on the adjacent
barrier and T-Top ramp transition.
The barrier expansion joint has a movement of
100mm
. Where the road surface expansion
joint movement is expected to exceed this
amount additional expansion joints can be used
on adjacent sections.
Expansion joints could allow extra deflection of
the barrier when hit. This can be prevented by
securing the barrier either side of the expansion
joint with intermediate anchors.
Adjust the gap between the barrier sections at
the expansion joint before installation to reflect
the situation - cold day large gap
–
hot, sunny
day small gap. Torque the nuts to
90-100 Nm.
