Page 21 - Haddonstone
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4.8 Reinforcement 7
For structural elements consideration must be given to the design strength and the 3
reinforcement detailing. Please refer to Section 8.4.6 of this manual for information.
Reference should also be made to BS EN 1992 and BS EN 1996. Alternatively, advice Unit should not be lifted with
should be sought from the individual manufacturer. lifting eyes or loops at angles
and always ensure that the
4.9 Lifting eye loop is screwed fully home
otherwise the thread can strip.
Cast stone has an advantage over • Where screw-in wire bond lifting loops
quarried natural stone in that units can are used, it is essential to ensure the
contain cast-in lifting attachments. These threads are screwed fully home, and
come as M16 or more delicate M12 cast- that a vertical lift is used – lifting capacity
in threaded sockets or as proprietary lifting reduces very rapidly with angled lifts.
clutch systems, and assist the Specifier
in meeting their CDM Regulations • When a threaded lifting eye has to be
responsibilities. used at a right angle (e.g. a socket insert
in the back of a panel) then articulated
For delicate placement of large stones, a loops are available.
rope block-and-tackle system, suspended
from a runway beam attached to the top • With two point lifts, use a spreader beam
of the scaffold, or even suspended from to avoid angled slings.
a crane hook, gives controllable, gentle
adjustment. Chain blocks should not be • Snatch loading by cranes cannot be
used as they may mark the stone. calculated for and must be avoided as it
will damage both stones and lifters.
Materials used for lifting inserts depend
upon the eventual position in the building, • Lifting stones directly with slings is
but in the great majority of applications unstable and can be unsafe.
where they are covered by subsequent
construction and encased in an alkaline • Webbing slings can damage unprotected
environment (i.e. mortar bed), BZP units arrisses.
are perfectly suitable and more cost-
effective than stainless steel. • Wire rope or chain slings are completely
unacceptable.
Safety of lifting operations has to be of
paramount concern and relevant sections
of HASAWA and Manual Handling
Regulations should be observed, and
Risk Assessments conducted before work
commences. The following points should
be considered:
