|Construction of a pier pit in 1960|
So, before any lifting could take place it was necessary to strengthen the base of the pit, by drilling steel rods into the concrete slab, stress more steel bars around and through the base of the pier to prevent it "exploding" apart and also to demolish then rebuilt the top of the pit wall (see below) to allow lateral jacks to be installed to prevent the pier toppling. All of these operations have taken a year of preparation.
|Pier pit wall strengthening|
|Installation of the carrier plates|
Working in tight areas means that Automatic Target Recognition (ATR) is critical. The distances measured are shorter than the minimum normal focusing range of approximately 1.5m. Similarly, ATR does not need ambient light and can be used in dark conditions.
The next step is to pour grout into the gap between the carrier plates and the pier base to ensure full load bearing...