Marshalls TJX Warehouse Mezzanine
Woburn, MA
This project involved the study and subsequent renovation of a 75,000 square foot concrete mezzanine used by a local clothing distributor. The mezzanine consisted of a concrete slab on form deck supported by steel bar joists, with an additional area consisting of hollow core pre-cast concrete planks spanning between steel beams and girders. The existing concrete slab was seen to be cracking and breaking up under the high concentrated loads from electric powered, and manually operated pallet jacks that were being used to transport loads throughout the warehouse. DEI decided that instead of replacing the mezzanine completely, a cost efficient structurally sound solution could be reached. The design consisted of gage metal sleepers placed onto the existing concrete, perpendicular to the steel bar joists below, and ResinDek manufactured "Xspan" composite wood panels fastened to the sleepers. As a result, all flexural loads resulting from equipment on the new panel deck would be transferred through the sleepers to the substructure below, allowing for activity in the warehouse to resume without further damaging the existing structure. It is estimated that this overlay solution saved over $2 million dollars by avoiding the demolition and replacement of the existing mezzanine structure.