In addition to the Acros and Strongboys, a further steel ‘needle’ was inserted to the external corner and another steel placed beneath the slab to spread the point load. After a few more checks and tightening up of the supports, the concrete lintel beneath the slab was cut out and the side wall partially demolished, exposing the edge of the slab in readiness for the steels.
The picture below, taken a little earlier in the week, shows the side wall slab in good condition:
The same can’t be said for the rear part of the slab, which has softened from water and salt damage over the years. As the picture below shows, part of the slab edge has broken away:
As we are relying on this edge (structurally: the slab sits into the web of the steel), we need to strengthen it using Sika Armocrete repair mortar. As a further precautionary measure, the bottom flange of the steel will be extended by 100mm to make sure it reaches sound concrete beyond the edge.