Several companies including Fischer, Spit and Hilti make resin-bonded anchor kits. They all work in a similar fashion, namely drill the hole, blow the hole out with an ait lione or blower gun, inject a measured quantity of a 2-pack chemical resin into the hole (supplied in a mixer gun), then insert the stud bolts and leave to set.
You can also get pre-made chemical anchors which have a glass/plastic vial attached to the end of the stud. With those all you do is drill the hole, clean it out, insert the anchor then hit the end with a hammer to break the vial and cause the 2-part resin to mix and set.
Yet another variation is to drill oversize, pack the hole loosely with epoxy mortar then knock-in a piece of studding. I've used this technique to hold a 4 tonne CNC router in place (in a concrete floor) and it hasn't moved yet.
In all the above cases your holes need to be accurately drilled into masonry, not mortar. You may have to hold the anchor in position using wire, tape, etc while the resin sets to ensure that the anchors are dead level. The resin normally goes off in 10 to 30 minutes depending on make
A fourth alternative might be to use a Rawlbolt. In one form they are made as a sleeved anchor with a captive threaded spreader nut holding a conventional hex-head bolt. This type can have the hex bolt replaced by a piece of threded studding.
Lastly if your shelves aren't too deep have you seen the
concealed shelf supports distributed by Hafele? Try
Woodfit or
Isaac Lord for retail quantities.
On any of these a local fastenings company (see Yellow Pages) should be able to advise.
Scrit
