15 Revision 33 October 2022
levered clear of the surrounding ground when the VRS is struck at the type
test angle.
4.4 Surface Mounted Posts
• Surface mounted posts are normally only used in locations where driven or
posts in sockets are not practicable, and therefore are often mounted on a
concrete slab of limited thickness. It must be ensured that such a slab is
adequately reinforced and is capable of resisting the overturning forces
incurred under impact at the initial type test angle. This should be
demonstrated through calculation and a design submitted to the overseeing
authority for approval.
• The foundation should be excavated to the correct depth in a continuous
length to at least the minimum length the design permits. Sides should be
shuttered where required and the reinforcing steel set in place. Reinforcing
should be designed in such a way that it is compatible with the use of
SAFEROAD anchorage systems which is the preferred method of anchoring
in a purpose-built foundation. However please note resin anchors can be
used.
• Concrete should be placed directly from the delivery truck and compacted
using vibration; posts on anchorages should be placed before the initial set
of the concrete and set to line and level, the concrete should be re-vibrated
around the anchorage after it has been placed in the concrete to ensure
there are no voids.
• Excess spoil should wherever possible be spread locally to avoi
d
u
nnecessary lorry movement and land fill otherwise it should be disposed of
at a licensed tip. Or at an agreed location on site for disposal by others in a
correct and environmentally responsible manner.
• Where the design organisation has deemed existing construction to be
suitable to provide a foundation for surface mounted posts the posts will be
installed on drilled anchors.
• The anchorage system must be installed in accordance with the
manufactures instructions and tests must be carried out as specified in
BS 5080 Part 1 to ensure the required strength has been achieved, see
table below. The frequency of the tests will be not less than 1 in 20 or as
specified in the contract.
• I
t is critical when fitting resin anchors that the holes are drilled to the correct
diameter and depth then thoroughly cleaned using clean compressed air
and or brushes.
• W
hen the resin anchor has cured, fasteners should be tightened to the
minimum torque and thread engagement. Posts should be sat on a grout
bed of between 10 and 30mm where the concrete conditions dictate.
Alternatively, a plastic bed with a compressive strength in excess of the
plastic moment of the post may be used.
• When the grout has set the anchors should be tightened to 60 to 80Nm
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