|Client & Main Contractor:||Jerram Falkus|
|Location:||Clerkenwell Road, east London|
Following the demolition of the existing building, to allow the construction of a new hotel, a large party wall was exposed that required stabilising before the development could proceed.
About 6.5m high, the original Victorian wall had been altered after bomb damage during the war and a new 100mm thick skin had been added to the 225mm wall behind. Built with only a mortar connection and no mechanical fixings, this new ‘hanging wall’, which was approximately 2.5m above the basement spread footing, had become debonded, cracked and unstable.
A fast and reliable solution was required as no work could be carried out on the new hotel until the wall had been fully secured.
A remedial programme was rapidly devised using a combination of Helifix masonry repair and reinforcement systems. At the bottom of the wall SockFix grout-filled anchors were used to provide vertical load bearing support, cracks were stitched with stainless steel HeliBars and DryFix retrofit wall ties were installed to reconnect the outer skin to the main party wall.
â— A total of 40 M16 SockFix grouted anchors, 8mm x 250mm, were installed in two staggered rows across the base of the wall at 300mm horizontal and vertical centres. These helped to secure the two walls while providing load bearing support. The SockFix anchors were inserted into clearance holes, core-drilled 50mm into the far wall, before being pumped full of grout to expand, fill any voids and become an integral part of the structure.
â— DryFix remedial wall ties were installed across the wall, in a diamond pattern 450mm x 450mm, to reconnect the hanging wall to the original wall.
The Helifix repair design and speed of installation meant that the wall was rapidly secured and the project suffered only minimal delays.