The RFA-Tech Loop Box is a simple and highly effi cient product that is used to join precast elements together or precast to in-situ. It is mainly used in the connection of slabs, walls and columns.
The connecting loop is made of high strength galvanised wire rope, and is protected by the galvanised metal box, which is sealed by a tape covering.
The Loop Box can be easily installed in both precast factories and In-situ. When the units are ready to be connected, the sealing tape is removed and the wire loop is locked into position using the JBS Locking device (Patent Pending). The JBS® locking device allows easy and accurate placement of the connecting rebar by ensuring the loops are held at 90° to the box axis.
The RFA-Tech Loop Box allows tension forces and horizontal / shear forces to be transmitted at joint positions.
The RFA-Tech Loop Box should be fi xed securely to the mould using any suitable fi xing method that will give a positive hold. The loop box should be installed with the tail within the reinforcement, however it is not necessary to tie the box to the reinforcement.
RFA-Tech Loop Boxes should be placed symmetrically throughout the joint, to ensure equal loading per box.
Ensure careful compaction of concrete around the RFA-Tech Loop Boxes.
On removal of the tape, the loop is then folded out and secured using the Patent Pending locking device within the box. Once in position the vertical rebar is installed through all the loops, ensuring the alignment of the wire is correct as the elements are being installed.
After the careful inspection, the joint can be fi lled with a suitable high quality grout, installed in line with the manufacturers recommendations.
The grouting compound of the joint should have at least the same concrete strength as in the concrete of the connecting precast or in-situ units.
The Joint should be fi lled as soon as possible after installation of the concrete elements.
When using RFA-Tech Loop Boxes the steel should be ribbed, 12mm (16mm for 140mm Loop Box) and to BS500.
For minimum edge distance and spacing please refer to Table 5 in the enclosed Technical Manual.
RFA-Tech Loop Boxes should be stored in dry conditions at all times.