Xi’an International Horticultural Expo

The Flowing Gardens and the Guangyun Footbridge

The World Horticultural Expo has become instigator and hub for the redevelopment of a large area between the airport and the centre of Xi’an. The ancient capital of the Qin Dynasty city, home of the Terracotta Army is today a major business centre for the vast interior of the Chinese mainland.

Plasma Studio, in collaboration with Groundlab, won this international competition with a radical self-sustainable vision. The project comprises of a 5000 m2 Creativity Pavilion, a 4000 m2 Greenhouse and a 3500 m2 pedestrian bridge set in a 37 ha landscape. The Expo opened in 2011 to approximately 15 M visitors.

Accomodationg and channeling the given flows of visitors whilst offering them choices and variety, Flowing Gardens unfolds into many sinuous paths, creating a network for intermingling circulation, landscape and water. These paths vary in width, ranging from main walkways and arteries to towpaths. In this manner, the park areas manifests a variety of scales in association with specific planting, surface treatment and lighting, providing a sandbox of experiences that range from the very intimate, with semi-enclosed, self contained, one-to-one spaces, to the very public, with communal plazas formed by wider pedestrian paths and a direct, uninterrupted visual link to the main hiatus on the site.

The project’s distinctive layout, reminiscent of a root system, articulates the hybridization of both natural and artificial systems. Rainwater is collected within pockets of wetland and recycled for irrigation.

The landscape legacy plan is phased to gradually transform from an international showcase for millions of visitors towards a sustainable local asset for the evolving community around. Local plant species help to reduce maintenance and ground the new Chan-Ba central park within its context.

The Creativity Pavilion

The building’s massing as three parallel volumes enable the landscape to flow in-between and beneath as well as inside. The interior is organized as multiple plateaus, systematically interconnected by ramps to form a continuous and multidirectional maze to be explored without a predetermined order.

The Creativity Pavilion – the main building of the expo – is located on the edge of the lake as the endpoint to the central axis, formed to articulate the interface with the lake and the framing of the pagoda on the other shore. It ties in with a series of piers that follow the landscape jutting out into the water. The built volumes are interwoven with the ground, blurring the distinction between landscape and architecture.

The building’s exterior articulation undermine traditional hierarchies and expectations: it’s read as a series of mounds when visitors arrive to it from the North, while in turn becoming sculptural and iconic when seen from its backside with three long cantilevered volumes hovering above the lake. The spaces beneath those large cantilevers are spatially as well as socially engaging: far away from the control and representational confines of the building’s entrance, groups of visitors gather on sloped decks to rest and reflect, in pleasant shade with sunlight reflected by the lake.

Through its materiality the Creativity Pavilion again manifests itself as an extension of the land, with the lower part being clad from the same stone panels as the ground around it. Further above solid cast bronze panels, a locally sourced material, is used to wrap the building’s sides and roof, while bands of greenery cover it like a tessellated net.

The Greenhouse

Conceived as a precious crystal, semi-submerged in splendid isolation, reached by boat across the lake, followed by a short walk from the shore, the greenhouse blends into the hillside. Visitors access the building through a prolonged cut, literally scooped up from the ground, emerging into a light-filled reception space. From here the visitor passes along a tessellated mesh of paths to three different climatic zones with corresponding plant environments.

The greenhouse has a horseshoe plan, creating a loop that changes radically in section to accommodate a series of unique planting and spatial conditions. With the interior and exterior ground planes gradually shifting in relation to each other, the visitor experiences a sequence of visual enclosures alternating with long vistas out and across. The horseshoe shape also generates an interior open-air courtyard, making it the natural center of the building and creating a three-dimensional web of interior and exterior circulation.