The Sheartech Grid system has been developed to overcome the problem of fitting many traditional shear links in deep slabs, where the angles, distances and number of layers of rebar can make fitment of these links very difficult.
The main application of this system is deep slabs of around 800mm or greater, generally in basements of high rise buildings or airport apron slabs.
Traditionally all slab reinforcement, including all layers of reinforcing steel and wire chairs, are placed before the required shear links are fixed, spanning the distance between top and bottom layers of steel. In thinner floor slabs this operation does not present a problem, as the reinforcing steel being small to medium diameter and the smaller element thicknesses allow some adjustment if required to enable shear links or a punching shear stud system such as Sheartech to be fitted.
In deeper concrete slabs the distances between top and bottom layers of reinforcement can make the placement of shear reinforcement particularly difficult, requiring steel fixers to try and place awkward shaped shear links over one
metre spans and greater. The weight of the heavier reinforcing bar used in these applications may mean that any adjustment required is not possible. Any small misalignments of the many layers of reinforcement can also prohibit the use of regular shear stud systems, as the path between all layers to place the stud is effectively blocked. The use of carpet type reinforcement systems, with heavy mats of reinforcement can also present difficulties if subject to any misalignment between top and bottom mat layers.
Sheartech Grid allows shear reinforcement in deeper slabs to be fixed in separate stages to allow easier and faster deep slab construction. Sheartech Grid also provides an alignment system for all layers of reinforcing steel to be placed against. The system features forged shear studs manufactured from grade B500C ribbed reinforcing bar, produced under the requirements of CARES Technical Approval 5028, combined with a full strength, parallel thread coupling system.