Lymington Hospital
Client: Rydon Construction
PFI 105-bed hospital involving a 3-storey ward, 2-storey entrance, 2-storey DTC and an energy/waste/management centre. The work includes sustainable drainage and an innovative flood scheme using a 'honeycomb' structure beneath parking.
Lymington New Forest Hospital is a community rather than a general hospital and provides 105 beds with four wards and two operating theatres, treating patients mainly on a daycare basis.
It replaces an existing community hospital and is being built under a PFI contract by Ryhurst, with associate company Rydon Construction as main contractor.
Content
The project comprises of two buildings on a 3.72ha greenfield site. The main hospital building has wards on three storeys, a two-storey Diagnostic and Treatment Centre, and a two-storey height entrance area. A separate single-storey building provides the hospital's energy, easte and management centre.
The Diagonostic and Treatment Centre is organised around a double height atrium-style waiting area, from where it is possible to see the reception areas of the various departments. It has a full height curtain wall glazing overlooking a courtyard on one side.
Challenges and innovation
Upton McGougan designed the building with a steel frame because it is a clean, reliable, quality assured product which can meet strict NHS standards for acoustic insulation and vibration levels. In addition, steel provides greater flexibility to form additional holes if it proves necessary to modify or extend later services.
Structurally the hospital building was straight forward, consisting of UBs and UCs on a 7m grid, extending to 7mx9m in the operating theatres, and with composite floors formed with Kingspan decking.
Vibration analysis of the structure was more complex, and therefore we enlisted the help of the Steel Construction Institute (SCI). The SCI's Dr Stephen Hicks had recently developed new guidelines for predicting the vibration response of floors.
The new guidelines were the culmination of a six-year research project. Through tests and back analysis of existing structures designed to the long-standing SCI 076, 'Design guide on the vibration of floors in hospitals', the SCI has developed a sophisticated analysis model to predict reponses to floors. On the basis of this model SCI published its new version of the guidelines.
The Lymington project had a non-uniform grid, numerous slab penetration for services, and movement joints. This put it beyond the scope of the simplified analysis.
From our plans Dr. Hicks developed a finite element model of the steel frame which was used to predict the dynamic properties of the floor. This data was then exported to software developed by SCI, which is used to stimulate the effect of people walking along corridors and to determine the response factors of the wards and operating theatres. From this we were able to rate response factors in sensitive areas and advise on whether the initial design was workable, or whether it needed refinement in certain areas.
The results were that in the ward areas, the structure met the requirements of Health Technical Memorandum 2045. For the operatine theatres, the SCI worked closely with us and the requirements for these areas were met by thickening the slab locally and increasing the sizes of the UB sections in this area.
Supply chain
The Steelwork Contractor finished two weeks ahead of schedule, and the whole project was completed ahead of schedule.