Welded wire fabric ( WWF )

What is Welded Wire Fabric ( WWF ) ?

Definition of Welded wire fabric ( WWF ) in Construction

Welded wire fabric. This is a material constructed of varying gauges of wire, dependent upon the design and the specifications. Either, sheets or rolls, of this material is used to embed in concrete assemblies such as sidewalks, or slabs, to reinforce the system and provide tensile strength to the system. The inclusion of WWF in concrete flatwork is intended to eliminate cracks from expansion and contraction as well as add to the overall strength of the concrete slab. The proper positioning of the WWF within the slab is important to ensure that the intended strengthening is maintained. There is a tendency for contractors to lay the WWF on the sub-base and simply try to pull it up into the wet concrete as they place the slab. This operation is done with wire hooks that are used to pull the WWF up into the concrete as the placement continues. This is not an acceptable procedure. The use of chairs or other types of accessories located on the top of the sub base and supporting the WWF in position is the proper method of locating the WWF correctly in the slab. The use of concrete bricks is also an acceptable method for positioning the WWF. Lack of proper positioning of this material within the concrete slab properly will eliminate the structural significance of the WWF. Most contractors prefer to use WWF in sheets as opposed to rolls due to the fact that the rolls are extremely difficult to position correctly. The flat sheets are easier to position and do not have the tendency to curl and cause issues as the concrete is being placed.