The project involved the construction of a multilevel automated distribution centre on a 16.7-hectare site. The footprint of the ground floor warehouse area is 50,850m2. In addition, there are three levels of mezzanine over the entire warehouse footprint giving a combined floor area of over 200,000m2. An office structure was provided to the front elevation and multiple ancillary structures such as welfare facilities, stair cores and driver areas around the perimeter of the building.
The warehouse is fully automated and uses robots on the 3 levels of mezzanine to move product around and facilitate the picking and packing of goods. The use of automation whilst optimising lightning-fast fulfilment also required adherence to strict client performance criteria for the mezzanine floor levelness and flatness which were designed and poured to a datum.
The main frame is piled due to the high foundation loads resulting from the multiple levels of mezzanine. Steel piles were adopted due to the high sulphate contents in the underlying Kimmeridge clays and the associated Design Sulphate Classification.
A detailed cut and fill exercise were completed optimising the main building finished floor level to balance site won material and minimise materials going off site, whilst ensuring that the drainage design tied in with off-site level constraints. Ground improvement works in the form of vibro-stone columns were adopted below the footprint of the building to minimise secondary settlement of the warehouse platform which had a max fill depth of 2 metres.
The external areas included construction of multiple retention ponds as part of the surface water drainage strategy. The drainage design necessitated routing runoff from four sub catchments through the retention ponds. Whilst the majority of the impermeable areas on the site are drained via traditional piped drainage systems, some Sustainable Urban Drainage systems (SuDs) features such as swales and filter drains in addition to the retention ponds were also provided.
The external concrete yard areas include HGV loading and parking on two sides of the building, with a total of 64 docks and more than 100 trailer park spaces being provided. Associated car parking for more than 800 vehicles was provided to the front elevation of the building. Additionally, a dedicated bus park was also constructed.
Finished external surfaces included concrete yard slabs, asphalt and block paving. Two commercial vehicle accesses and two separate car park accesses onto the public road network were provided together with cycle and pedestrian paths. Earth bunds constructed to the perimeter of the site provide noise and visual screening to the surrounding lands.
EirEng provided full civil and structural engineering services from the planning stage through to construction and Practical Completion.