Our client, Mercury Contracting Projects Ltd. has proposed to build a three-storey amenity pavilion adjacent to the FIMBank building and to the listed Mercury House. It is the client’s intention to maximise potential ground floor space, so the new building will occupy all available space.

The most iconic feature of the pavilion is the roof that provides its unique appearance. The intended use of the pavilion is a café at ground floor level and a bar or night club in the basement. All pavilion levels will be linked by a spiral staircase.

There are three additional basement levels that were designed by others as a concrete frame with precast planks up to level B3. The Pavilion itself comprises level B1, the roof, mezzanine level at B2 and the spiral staircase that will link B3, B2 and B1.

The B1 slab will only be supported on the perimeter wall and on an intermediate column. This slab will be supporting the whole pavilion’s roof, except for the central column that will be extended up to foundation level.

PROJECT DESCRIPTION.
The curved roof is probably the most noticeable feature of the Pavilion; its shape and the glazing façade will clearly contrast with listed Mercury House and other existing buildings in the town of Saint Julian’s.

Regarding the choice of structural materials, discussions were carried out between the client, his construction team and the design team. It was agreed that reinforced concrete would be the main structural material, however, the main central column and the elements required to support the edge of the roof and to restrain the glazing façade, are made of steel.

As it is a client request to have a column free space at basement levels, we have designed the piazza level with downstand beams spanning 20m and supported on the perimeter wall. To ensure the adequate structural behaviour and the comfort of the piazza, a footfall analysis was carried out.

KEY ENGINEERING SOLUTIONS.

• Building over an existing basement structure before the Pavilion design concept was developed – most of the structure was justified apart from a single column to formation level below a new internal column
• Building in a constrained site adjacent to FIMBank, Mercury House, Triq Elija Zammit Street and Triq San Gorg Street
• Creating the curved roof form with limited and varied supports, including two internal columns, rear core walls and slender façade mullions, all with exposed structure and a 60min fire rating
• Creating a large column free area below the ground floor at B2 with 20m span concrete beams between the perimeter walls
• Polystyrene shuttering construction – concrete shell
• Steel spiral staircase wrapped around the main central column with cantilever treads and balustrading