Taking Flight in the Gardens

Taking Flight in the Gardens

Fitzgerald Park, in the City of Cork, Ireland, was the site of the 1902 Cork International Exhibition, an event that brought the world to Cork to frolic on rides like the great water chute, and gaze upon wonders of the dawning Twentieth Century in the Industrial Hall and the Machinery Hall. It was such a success that they held it again in 1903.

In the city today, many would like to see the world come to Cork in greater numbers, again. They have turned to Fitzgerald Park, again, to help make Cork more of a tourist destination.

The recent remodeling of the park’s Mardyke Gardens was designed by Cunane Stratton Reynolds. The €2.3 mil project – 80% funded by Fáilte Ireland under its Tourism Product Development Scheme – includes a restoration of the large fountain and ornamental pond from the 1902 exhibition; a rather unusual garden featuring stainless steel spheres the size of large beach-balls; a prize-winning pink “pod” from celebrity gardener Diarmuid Gavin’s Sky Garden, which won the gold medal at the 2011 Chelsea Flower Show; and a performance pavilion facing a sunken lawn and featuring an iconic canopy that appears ready to sail into the sky.

The pavilion canopy is made entirely of glass fiber reinforced polymer (GFRP).

The parasail-like structure, designed by Dormody Architects, is intended to host musical and theatrical performances, as well as outdoor movies. It was originally conceived as a steel frame with either a plywood or composite covering. AM Structures, a specialist in large-scale composite structure fabrication, began working with Gurit on the engineering and materials for the shell. As they worked on the design of the shell, they realized that it almost had enough strength to stand alone, without the steel frame. With some enhancement, they could make it entirely out of GFRP, eliminating the steel except for the anchor points at either “foot” of the structure.

The choice simplified the structure in several ways. However, its sail-like shape catches the wind very effectively.  The design had significant wind-load challenges to meet, and its minimal weight only made that problem more difficult. A careful engineering of the loads using Finite Element Analysis was conducted.

The final design features two shells, inner and outer, each a sandwich panel of GFRP skin over a foam core. The shells are joined by an array of ribs and flat webs to keep the separation between the shells and to help direct the huge windload forces down into the “feet” of the structure. (For an in-depth discussion of the engineering and construction of the pavilion canopy, see Karen Wood’s excellent article in Composites World Dec 2014.  There is also a nice, short video about the pavilion, made about one month before the gardens re-opened, posted by The Irish Examiner.)

Since the canopy was being fabricated in the Isle of Wight, shipping it to the site in Ireland imposed some restrictions on design.  The front tip of the sail was manufactured as a separate unit, to make it more compact for shipping.  The two parts were joined at the project site.

The reborn Mardyke Gardens was opened in May, 2014.