Beijing-based architecture studio OPEN has revealed its curvilinear tower on the coast of Yantai, a booming city on the coast of the Yellow Sea, China. 

Named Sun Tower, the 50-metre high structure is set to become a new landmark with curvilinear form, half-sliced silhouette and porous structure opening up itself towards the coast. 

Currently under construction at site, the Sun Tower comprises a semi-outdoor theatre on the ground, a winding exhibition space, and a library in the sky. The project is expected to be opened to the public in 2024.

The project was awarded the Jeu d’Esprit Special Prize of AR Future Project Awards 2021.

The building features a unique semi-outdoor space at the top, which is referred to as the "phenomena space", designed for people to observe the magnificent natural phenomena throughout the year.

"The name of the city of Yantai means "Beacon Tower" and was derived from the series of watchtowers built during the Ming dynasty as a warning against impending attacks on the coastline," explained OPEN.

The city wanted to create a landmark on the coast, its fast-developing new district, one of the earliest special economic zones in the country and an industrial powerhouse today. 

Semi-outdoor theatre

Based on the characteristic features of the site, OPEN envisioned a more purposeful structure that can "evoke the ancient rituals of nature-worship while providing much-needed cultural facilities in the newly urbanised district." 

"Yantai is also often noted for its beautiful views of sunrise across the Yellow Sea, something the architects would embrace in their design," as the studio noted.

OPEN is closely working with world-renowned engineering firm Arup to build this tower. The form of the building is shaped with a large curvilinear structure. The shape of the building is designed as a result of careful studies of the sunlight and appears sliced open by beams of light, revealing the interior spaces to the majestic sea.

Library and lookouts

Inside, the building features a gently sloping plaza. Conceived as a composite shell structure, two layers of slanted white concrete shells are connected and braced by horizontal slabs and ramps.

"Today it's so important to find ways to connect and embrace nature, we wanted to keep this central to the concept of the Sun Tower and pay respect to the power of the surrounding landscape. Immediately when we conceived of the design we wanted to reference ancient human rituals, honouring the sun, moon, and stars, and offering a space for reflection and contemplation," said LI Hu + HUANG Wenjing, founding partners of OPEN. 

Exhibition Space

"On the other hand, we also wanted to ensure the building had an authentic purpose and function, something that would be of benefit to the citizens of Yantai rather than just a folly on the beach." 

"Creating spaces that juxtapose the incredible ocean views with the forward-thinking digital exhibitions that explore nature," they added.

The concave inner shell of the Sun Tower is facing the ocean, which also acts as a sound collector and absorbs and amplify the sounds from the sea. 

Space between the upper and lower shells

The smaller upside-down upper shell houses a light-filled library and the "phenomena space" offering a breathtaking view of the ocean and the sky above. 

An big oculus in the centre of the phenomena space’s ceiling allows rainwater to enter and fill a small pool underneath in the summer. In the winter, the pool will be dry and used as a fireplace.

In the early design phase, working with French firm dUCKS scéno, OPEN conceived the exhibition spaces inside the building to provide a focus on digital exhibitions and big data technologies, while also simultaneously being an energising force for the long-term growth of this new city.

Library interior

Aric Chen, the current General and Artistic Director of Het Nieuwe Instituut in Rotterdam who, in his previous role as Director of the D&I Curatorial Lab at Tongji University in Shanghai, consulted on the project from the curatorial perspective, working with OPEN to develop this idea of a digital museum that would link the digital with the phenomenology.

"OPEN has a remarkable ability to take on an architectural assignment and infuse it with meaning and purpose; in their hands, form follows content. From educational institutions to cultural projects across China, they've shown time and time again how architectural innovation and social innovation go hand in hand," said Aric Chen. 

Phenomena space

At the base of the tower, there is a big plaza also designed by OPEN, a shallow pool completes the circular shape and features misting devices and spouting fountains. 

"A specially designed water channel cuts across the plaza—a ruler of time—this is the straight line that the shadow of the Sun Tower will follow on the day of the equinox," added OPEN. 

A series of elliptical rings are designed in the pavement pattern; the intersections between the rings and the water channel mark the building shadow’s footprint at specific hours on the equinox day. 

At one of the outer rings, a series of fountains were designed to celebrate the 24 Solar Terms of the Traditional Chinese Calendar; on normal days they are synced with high and low tides. 

Birds-eye view

"These carefully planned water features add to the sense of liveliness, while also reflecting upon the city’s long history of oceanic culture which is rare in China," according to OPEN.

Sun Tower will also be featured in OPEN’s forthcoming book Reinventing Cultural Architecture: A Radical Vision by OPEN published by Rizzoli in April 2022.

OPEN was founded by Li Hu and Huang Wenjing in 2008 in Beijing. Known for its monumental and innovative projects, OPEN designs projects in urban design, landscape design, architectural design, and interior design across China and beyond.

The UCCA Dune Art Museum on a quiet beach along the coast of northern China’s Bohai Bay and The Chapel of Sound, a monolithic open-air concert hall outside Beijing, are among key projects of OPEN.

Construction photo

Geometry sculpted by sunlight

Diagram of movement of shadow during the equinox

Physical Model

All images courtesy of OPEN.

> via OPEN