Technical requirements for safety in metal scaffolding – Cast-in and drilled-in anchorages used as ties

5.1.3  Cast-in and drilled-in anchorages used as ties

(a)    Cast-in anchorage

In some cases, it is possible to ‘build in’ scaffold ties into the fabric of the building during construction. A variety of screwed plates, sockets and nuts are available for setting into concrete during pouring, in a similar manner to formwork anchors, for subsequent use as scaffolding  ties. The  appropriate  bolts  should  be  welded  to scaffolding tubes or scaffolding fittings for use as tie attachments. Alternatively, the bolts may be used directly to attach this type of fitting. Ring bolts may also be used.

(b)    Drilled-in anchorage

A   variety   of   expanding   anchor   sockets   are   available   for fixing into holes drilled into hardened concrete. The attachments are similar to cast-in anchors. Care should be taken that the facade  material  is  a  structural  material  and  not  a  surface cladding with little or no strength. Anchor sockets and ring bolts rely  on  an  expanding  wedge  to  secure  the  anchor  into  the pre-drilled  hole. As  such,  overtightening  should  be  avoided  to prevent damage of the base material of the pre-drilled hole. Torque wrenches or other special tools supplied by the manufacturers should be used to fix the anchors, the ring bolts or other devices inserted and tightened by hand. Drilled-in anchorages should be tested before use.

(c)    Anchorages should be tested to ensure that they are of sufficient strength. They should be tested in accordance with BS 5080 or other equivalent national/international standards or provisions.