Cube Cost Consultants Limited
The development falls within the Aldgate Masterplan area and City Fringe regeneration zone and forms part of the wider regeneration of this area of London which is currently undergoing large-scale changes.
This 23 storey building with two basement levels provides 168 high quality serviced apartments together with ancillary cafe bar and restaurant facilities located on a previously brown field site at 15- 17 Leman Street in East London. CampbellReith was responsible for the delivery of the structural design of the superstructure, substructure and foundations and for the design of underground drainage and external hardstandings.
The ground and first floor are occupied by the restaurant and cafe bars which open out onto a street level terrace at ground floor. The ground floor also accommodates the reception area for the upper level apartments and an undercroft service yard area and substation.
The architectural appearance is enhanced by a two storey high colonnade of circular columns around the complete perimeter of the base of the building terminating in a podium slab at second floor above which then extends 21 storeys of curtain walled glass elevations housing the apartments.
The building is very slender about its north-south axis with an aspect ratio of height to width of over 6 which required careful consideration in the design and location of the stair and lift cores such that they provided the required lateral stability to resist wind loads yet minimise their impact on the area of building footprint available for the apartments.
Wind modelling and analysis were carried out to determine loadings and deflections on the frame and to check that horizontal accelerations due to high wind loadings were not of a magnitude that would be perceptible to the occupants of the upper storey apartments.
An insitu reinforced concrete frame is used throughout with ‘blade’ columns located within the party walls between apartments at upper floors. Stability is provided by the two stair and lift cores.
Typical upper floor levels utilise a 225mm thick slab however a 1.0m thick ‘podium’ transition slab is provided at second floor level to transfer the apartment column grid to a larger span grid provided within the lower level restaurant and cafe bar areas and to distribute loads to the circular column colonnade.
The single level basement is formed within a secant bored pile wall waterproofed using a cavity liner system. Main foundations are formed using a piled raft with 900mm diameter bored piles extending into the London Clay.