Researchers at ETH Zurich have completed Tor Alva, the world's tallest 3D-printed concrete tower, in Mulegns, Switzerland.
The 30-meter, four-story modular structure demonstrates sustainable building practices.
It's the first multi-story structure with load-bearing columns fully created through 3D printing, including built-in reinforcement.
The 3D concrete printing method employs two coordinated robots.
One extrudes concrete layer by layer, while the other places reinforcement.
A specially designed fine-grain concrete hardens quickly due to a custom additive.
ETH researchers developed a hybrid reinforcement system for enhanced structural integrity.
Horizontal steel rings were embedded during printing.
Vertical rods were added post-printing and filled with self-compacting mortar.
The tower's upper sections incorporate prestressed rods to improve crack resistance.
The modular design allows for disassembly and relocation, aligning with circular construction principles.
Dry connections and prestressed joints facilitate component reuse.
Corrosion-resistant stainless steel replaced traditional rebar to improve durability.
The tower is designed to accelerate carbonation, reabsorbing atmospheric CO₂.