St Johns Quarter – Manchester Goods Yard

Interspan continues to play a part in the redevelopments of the city of Manchester after being contracted to provide the post-tension slab works for The Goods Yard.

Sitting on the former site of Granada Television Studios is St. John’s Quarter – a new development with multiple spaces for commercial, retail, office, residential and leisure. The development is taking place in the periphery of Manchester City Centre, with Interspan being involved with Manchester Goods Yard – the first phase of the whole project.

Design of Goods Yard

Approached by Allied London, Curtin’s Consulting was tasked with accommodating 30, 800m2 of internal office accommodation, as well as commercial units at ground and mezzanine levels. The double-storey basement takes the brutalist-inspired building to over 10 storeys tall.

In the event the scheme was partially completed up to first-floor level, foundation and basement were designed to have sufficient mass, so that buoyancy from the hydrostatic uplift generated by the high-water table could be managed. Raft slabs were constructed off the underlying intact rock, to provide efficient arrangement and utilise the benefits of the relatively shallow sandstone.

Use of Reinforced Concrete at Goods Yard

The benefits of reinforced concrete were employed in the design in various ways:

• 3 reinforced concrete core walls extended from the foundations to provide stability to the structure.
• A reinforced concrete frame solution was used to provide a more robust structural arrangement, compared to a traditional steel frame.
• Spatial efficiency was maximised in the basement level car park from the use of reinforced concrete.

P J Carey Contractors were the frame contractor for the scheme and appointed Interspan to design and execute the post-tensioned concrete flat slabs from Level 00 Mezzanine up to Level 08 transfer structure. The slabs ranged between 250mm and 400mm, with beams ranging between 450mm and 750mm.

This led to a total concrete volume of 8, 650 m³ being used, with a 30,800m² area.

The 50-year design life of the concrete slabs installed offer good acoustic resistance and fire resistance, so the client’s need for a 2-hour fire safety rating could be well-satisfied. The post-tensioned slab construction sought to simplify lateral distribution of services, due to flat soffits being generated – this simplified coordination.