This year’s temporary Serpentine Gallery summer pavilion, in London’s Kensington Gardens, opened last week. Designed by Chilean architect Smiljan Radić, the pavilion is a blocky torus resting lightly upon a set of five sandstone boulders in the daylight. Photograph © 2014 Iwan Baan
The 2014 Serpentine Gallery summer pavilion officially opened in London’s Kensington Gardens last week.
July 1, 2014—Designed by Chilean architect Smiljan Radić, this year’s temporary Serpentine Gallery summer pavilion in London’ Kensington Gardens is a sculptural form that plays with texture and light. A blocky torus resting lightly upon a set of five sandstone boulders in the daylight, the pavilion transforms into a softly glowing, lamplike cylinder hovering above a hollow in the evening hours.
The 350 sq m pavilion is located on the lawn of the Serpentine Gallery; it is the 14th year that the gallery has commissioned a design for its now famous summer pavilion series. According to the gallery, Radic intended his design for this year’s iteration to join the history of small romantic follies that were popular in gardens from the late 16th century through the start of the 19th century.
The London office of global engineering firm AECOM provided the engineering and technical services for this year’s design as well as the cost and project management services. York, United Kingdom-based Stage One were the contractors for the pavilion, which had to be erected on-site in a narrow six-week window and will be dismantled and moved to a permanent location after the pavilion’s summer season ends in October.
To create the appearance of heavy solidity for this year’s pavilion—without the weight—the design team used multiple layers of glass-reinforced plastic (GRP). The GRP was fashioned on a mold off-site to create a 25 m diameter torus shell approximately 8 mm thick, according to Thomas Webster, MEng, CEng, MIStructE, the associate director of the London office of AECOM. The shell was then cut into sections for delivery to the site and carefully pieced together with additional layers of GRP to reconnect the pieces and bring the shell to its current 10 and 12 mm thickness. “[GRP] is good at creating form, so you can use it to create curvature and even some quite pointy, sharp objects if you need to,” Webster says. “But in our case, we’ve got this sort of beautiful torus shape and the outer layers of the GRP are put on in multidirections to give you a real texture and to give you the contrast between light and dark as the light shines through the structure.”
At night, the pavilion transforms into a softly glowing, lamplike
cylinder hovering above a hollow in the evening hours. A thin
glass-reinforced plastic shell encapsulates a steel frame that
supports the elevated structure and its internal walkway.
Photograph © 2014 Iwan Baan
The pavilion is elevated up to 2.5 m above the ground by a structural steel platform located atop five 200 mm diameter steel columns. “The whole structure—the covering [creating] this torus—is formed from glass-reinforced plastic, which is used as a shell and totally encapsulates the floor and the structural steel work, but also creates a canopy above,” Webster says. The steel columns extend first through the GRP and then through bored holes in the boulders scattered around the site and are founded upon 2.5 m square by 500 mm thick concrete pad foundations, according to Webster.
“The structural steel solution is essentially a spine beam with cantilevers off of it, and that allows us to keep the structure to a minimum while still maximizing spans and minimizing the number of supports that we have,” he says. The cantilevers are a reasonable 3 to 4 m with the spine beam spanning 9 m, according to Webster.
A timber-joisted interior floor provides safe passageway for visitors to the pavilion, and space for the internal café that the pavilion hosts each year. With the thin GRP shell creating a 9 m curved span, balancing the need to support the curvature of the shell with the minimal amount of steel work so that it could fit within the shell’s walls and yet still control the potential vibration effects of people walking within the pavilion was tricky, according to Webster.
“We have a lot of torsion in the steel frame because the floor is cantilevered out from the central spine,” Webster says. However, because of these stresses, steel was the obvious choice to support the structure, he notes.
An approximately 8 mm thick glass-reinforced plastic (GRP) shell
was created off-site by building up multiple GRP layers. The shell
was then cut into pieces for transportation and reassembled
on-site with additional layers until it reached between 10 and
12 mm in thickness. Photograph © 2014 John Offenbach
In the hollow beneath the pavilion, the design team has added a 15 sq m, 400 mm deep attenuation layer to act as a large soak-away, according to Webster. The layer uses loosely compacted type 3 material with approximately a 30 percent void ratio, he says. “That increases the availability of the ground to store water, and that then should stop the lowest point of the site becoming waterlogged,” he says. The attenuation layer is finished with a layer of turf measuring 75 to 100 mm deep.
As with previous pavilions, this year’s offering will host evening events that bring together art, poetry, music, film, literature, and theory. Last year’s design by Japanese architect Sou Fujimoto was the most visited in the history of the gallery’s summer pavilion program, with almost 200,000 visitors recorded, according to the gallery. (See "Serpentine Gallery Pavilion Features Cloudlike Design, " on Civil Engineering online.)