|Location:||Stockport, Greater Manchester|
|Approved Installer:||Specialist UK Restorations|
Over a 12 month period cracks had appeared at one corner of Hathaway Close, a two storey block of 24 age exclusive flats built in 1969 for older residents.
A survey by engineers from Stockport M.B.C. confirmed that this was due to subsidence resulting from poor ground conditions and defective drainage. Stockport Homes, the arm's length company that manages Stockport M.B.C.'s housing stock, called in Helifix to undertake the necessary repairs.
An earlier soil investigation had identified suitable bearing strata at a depth of approximately 5m so Helifix proposed an economical combined solution. Helifix micro-piles would rapidly stabilise the foundations while the Helibeam System would repair damage to the superstructure.
Seven helical micro-piles were installed to a depth of 5.5m and 1m apart. Following minimal excavations at the foot of the foundations, the helical piles were "screwed" into the stable subsoil, using lightweight, hand-held equipment until the specified torque was achieved. The piles' "L" shaped brackets were then jacked up under the foundations to support the required building load.
Above ground, pairs of stainless steel HeliBars were bonded into the mortar beds around the corner at the required levels using HeliBond cementitious grout. These formed deep masonry beams, using the existing brickwork, which stitched the cracks and distributed the building loads.
Once the ground, cracks and mortar beds had all been made good there was little visible sign of the concealed non-disruptive piling and masonry repairs which restored stability to Hathaway Close.
To download the case study in PDF format click here