HeliBar is a helical stainless steel reinforcing bar, with substantial tensile properties, used for strengthening and stabilising masonry in both new build and remedial situations.
HeliBars are bonded into cut slots at pre-determined levels in the masonry using HeliBond thixotropic cementitious grout, it is the composite action between the HeliBars and HeliBond that provides the core element of the Helibeam System, making it such a versatile, reliable and successful masonry repair system.
The length of the HeliBar varies depending upon the application. Longer lengths are used, normally in pairs, to form masonry beams that secure large areas of masonry, distributing the structural loads and overcoming various problems caused by foundation movement. They are also installed in the existing masonry to unobtrusively create or reinstate failed lintels. In shorter 1m lengths, HeliBars are used individually to perform reliable and permanent crack stitching.
HeliBar starts as round stainless steel wire with a typical 0.2% proof stress of 500N/mm² but after the cold forming manufacturing process that creates the helical hi-fin design, this more than doubles to around 1100N/mm². This means that HeliBar, with its relatively small diameter, provides substantial tensile properties to the masonry, particularly when combined with HeliBond grout which locks between the fins and bonds to the masonry. Consequently, the well proven Helibeam System has a variety of remedial and new build applications.
Using 400mm long bars, installation is very similar to crack stitching. The bar is installed across the joint, as with cracks, but is only bonded at one end. The other end is allowed to move freely by inserting it into a sleeve which is bonded into the masonry.
1. Rake out or cut slots into the horizontal mortar beds, a minimum of 500mm either side of the crack
2. Clean out slots and flush with clean water and thoroughly soak the substrate within the slot
3. Using the Helifix Pointing gun, inject a bead of HeliBond along the back of the slot
4. Using the HeliBar insertion tool push one HeliBar into the grout to obtain good coverage
5. Insert a further bead of HeliBond over the exposed HeliBar, finishing 12mm from face and ‘iron’ firmly into the slot using the HeliBar insertion tool
6. Re-point the mortar bed and make good the vertical crack with CrackBond TE3