Holdfast Training Services Trial Blog

Quick blog for interest as seems to be something that isn’t done particularly often.

Shell House facade is to be retained (previous blog (‘loads of temporary steel’) explains the retention structure). I was asked how the plunge columns were constructed prior to demolition. Here is how it was done:

• Entrance from Wynyard lane increased and slab demolished to allow access for rig to drive in and down the ramp to basement level.
• Demolition of two slabs to allow access for lift in of columns (existing void from L1 up (see 1^st and 2^nd photo)).
• 21m plunge columns constructed.
• RC crane base cast on top of the 4 plunge columns.
• Stability core and retention system built from crane base.
• Crane tower constructed within stability core.

Figure 1 – Plunge Column Construction Photos