A scheme is to be developed for a 22-storey residential tower in the waterside redevelopment area of a regional city centre. The building has a one-storey basement and two storeys of retail area at ground and first floor. The residential tower consisting of studio, one- and two-bedroom apartments comes off a podium deck at level 2. One face of the tower is sloping up to Level 18. Level 18 is a garden level with a smaller four-storey block rising from the garden level housing the two-storey penthouse apartments.
The new tower is situated on a prominent site in a redevelopment area close to the waterside within the site of the old docks. Any external concrete should be considered to be in exposure class XS1 to take account of the seaside location. The basement car park is accessed via a ramp in the north west corner of the site and needs to provide 30 car parking spaces and 60 bicycle parking spaces. The car parking is to be solely for the use of the residents of the tower, and will not be used by the users of the retail space.
Access between the basement and the residential levels will be via an access core containing one staircase and two lifts, one of which is to be a fire-fighting lift. The top penthouse levels will have a communal lift and a staircase, with internal staircases between the floors within the penthouses. The architect has provided a typical layout for the apartments at Level 9 and for the penthouse levels. The other levels will be similar although as the north facade is sloping, the layouts towards the top of the tower will be modified to suit the smaller area. The number of apartments per level will therefore reduce on the upper levels. Structure can be placed within the walls shown on the architect’s plans and in the external walls.
Verification of structural viability should be carried out in accordance with current Eurocodes. Entrants should clearly state the documents used in support of calculations. Materials specifications should be defined to current British Standards. Fire resistance of two hours is required.
- Precast concrete cladding including glazing 2.0kN/m²
- Car parking 2.5kN/m²
- Retail 5.0kN/m²
- Residential 2.5kN/m²
- Circulation 5.0kN/m²
- Podium deck 10.0kN/m²
- Garden deck 10.0kN/m²
- Roof 2.5kN/m²
These loadings include an allowance for services. All values are characteristic values.
The site is flat, 0.5km from the sea. The value of fundamental basic wind velocity, Vb,map, should be taken as 23.5 m/sec (based on BS EN 19911-4:2005). Snow loading may be neglected.
||Depths below ground level
||Ground level to 3m
|Dense sands and gravels
||SPT ‘N’ blows = 40
φ’ = 40°
Ground water level should be taken as 1.0m below ground level.
Architects drawings can be found in the competition brief, here