St Johns College Oxford
Mason UK were specifed by Arups and contracted by Kingerlee Construction to supply and install 400 square meters of jack up floating floor for St Johns College at Oxford University.
Mason UK designed and installed 3 jack up floors for the Gym, Events Room and a Music Practise Room in the basement. As the basement was below the water table the area needed to be tanked. The jack up floating floor slabs therefore had to be cast on top of a waterproofing RIW membrane. In order to avoid crushing the RIW, at the jack locations, the recesses were filled with high strength grout and covered with a spreader plate to take the point load of up to 14kN of the jacks. Between the jacks, the depressions in the RIW were filled with sand.
An added complication in the Gym meant that Electrical floor boxes were required to be cast into the floating floor to control the gym equipment. This was not a problem as the floor boxes were tied to the mesh with the connecting conduit running between the layers of reinforcing mesh.
This was a very tight site and access was limited. A small concrete trailer pump was used to pump the concrete almost 90m to the far end of the furthest slab. Mason UK organised the supply of the concrete pump and the concrete finishing using their own approved sub contractors.