Zaha Hadid Architects and Block Research Group unveil 3D printed concrete bridge in Venice
A free-standing pedestrian bridge built from 53 3D printed concrete blocks and devoid of reinforcement is now open to quiet pedestrian traffic in Venice. Even if striatus does not carry pedestrians on one of the city’s famous canals, this one-of-a-kind structure is now open to crossing the park to the verdant Giardino della Marinaressa during the Venice Architecture Biennale 2021.
The approximately 40-by-52-foot arched walkway was designed by the Calculation and Design Group of Zaha Hadid Architects (ZHACODE) in collaboration with the Block Research Group (BRG) at ETH Zurich University and a multinational cohort of project partners including: Holcim, incremental3D (In 3D), and Ackermann GmbH, the latter of which created the CNC timber frame of the bridge. ZHACODE is credited with the design and manufacturing design of the structure; BRG has partnered with ZHACODE on these elements as well as on structural engineering, logistics, assembly and construction of the bridge, which is the first 3D printed concrete load-bearing bridge to be made without steel reinforcement or mortar. .
As detailed in the Striatus team press documents, the project focused on reducing as much as possible the environmental impact associated with reinforced concrete structures. Using a new type of concrete for additive construction developed by in3D with researchers at ETH Zurich, the compression-only masonry-style Striatus is “stable due to its [funicular] geometry only, “while its unique design” allows forces to move to the soles, which are tied together on the ground. “
The project team elaborated: “Concrete is not applied horizontally in the usual way, but rather at specific angles such that they are orthogonal to the flow of compressive forces. This keeps the printed layers in the blocks pressed tightly against each other, without the need for reinforcement or post-tensioning.
“This precise method of 3D concrete printing allows us to combine the principles of traditional vaulted construction with digital concrete fabrication to only use the material where it is structurally necessary without producing waste,” added Philippe Block. , professor at ETH Zurich who heads the university’s BRG alongside Tom Van Mele.
In addition to its low waste nature, Striatus can easily be taken apart, moved and rebuilt multiple times in different locations due to the fact that it is built without mortar or binder. When the truly circular structure reaches the end of its useful life, it can be separated and recycled in its entirety. A post-Biennale location for Striatus, which will remain visible and pedestrian-friendly at the Giardino della Marinaressa waterfront until November 21, has not been announced (if there is one).
Beyond the ephemeral gateways erected at the Biennale to demonstrate promising advanced computer design methods and emerging robotic 3D printing technologies, the project team presented what they call a “plan to build more with less” . Specifically, BRG, in partnership with Swiss building materials giant Holcim, is seeking to disrupt the construction industry with a greener alternative to reinforced concrete floor slabs. This new unreinforced flooring system would require only 30 percent of the volume of concrete and 10 percent of the amount of steel compared to its conventional counterpart.
With an estimated floor area of 300 billion square meters to be built worldwide over the next 30 years, ”the project team explained,“ and floors representing more than 40% of the weight of most buildings in high rise introducing the principles demonstrated by Striatus would truly disrupt the construction industry by transforming the way we design and construct our built environment to meet the defining challenges of our time.
Striatus, which aims to establish a “new language for concrete that is digital, environmentally advanced and circular by design”, is not the first time that ZHA and UTH Zurich have teamed up to design and build a concrete creation. . In 2018, the London architectural firm and BRG collaborated on KnitCandela, a 13-foot-tall curved concrete pavilion at Mexico City’s Museo Universitario Arte Contemporaneo that was formed with a 3D knitted frame.