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T op-down construction requires columns to be plunged into piles to tight structural tolerances. Balfour Beatty Ground Engineering (BBGE) are experienced in achieving these high standards. CONCEPT Plunge columns can be installed into rotary bored piles to allow for a ‘top-down’ construction sequence, 'launching' structures before the basement is excavated. By adopting this method of construction the client can gain advantage of a reduced construction programme. Plunge columns have been used in the past but it is only recently that they have been brought back to the forefront of construction and BBGE are helping to drive this resurgence. CONSTRUCTION PROCESS Generally the construction process is as follows; a rotary bored pile is excav ated to the required depth, a reinforcement cage is then installed and then the void is filled with concrete stopping the required distance below ground level. Whilst the concrete is still wet a hydraulic plunging frame is installed within the temporary casing and then the plunge column is installed to structural tolerances. The concrete is then lef t to set in the pile and once this is complete the empty bore PLUNGE COLUMNS www.bbge.com
