Concrete Joint and Saw Cut Preparation
The following guidelines are offered as a point of reference for a “typical” installation of a synthetic sports floor. It is the responsibility of the architect-engineer to review all existing soil and site conditions and thereby specify the necessary drainage, reinforcement, thickness, mix ratios, slab segments, etc. prior to the placement of the concrete slab.
In addition to the initial shrinkage and curling due to curing and drying, concrete will continue to expand and contract with changes in site temperature and moisture. These changes may produce random cracks in a hardened concrete slab unless they are properly controlled.
To address the random cracking, expansion, and contraction many concrete slabs have construction joints and/or saw cuts throughout the slab. Any construction joint shall be keyed, to restrict movement, as designed by the architect-engineer. Isolation or expansion joints typically are the most problematic. Slab movement along these joints can cause issues with the synthetic surface; i.e. the visual telescoping of the crack through the synthetic surface.
MFMA recommends consulting your Sports Floor Contractor or synthetic floor supplier for their specific experiences on construction joint and saw cut preparation; as this can vary with the type of synthetic floor being installed.
Disclaimer: The MFMA provides general information to architects, specifiers and consumers. The MFMA, its members, officers and agents disclaim any responsibility whatsoever for the accuracy or applicability of these guidelines under all circumstances and conditions.