Thai Siam Cement Group (SCG) has delivered a 3D printed pedestrian bridge across Bangkok’s historic Ong Ang Canal, marking one of the earliest examples of digitally fabricated public infrastructure in Thailand. Completed in 2025 as part of the Bangkok Metropolitan Administration’s program to rejuvenate the canal district, the project merges advanced construction technologies with cultural references and research into lower-impact materials.

Lightweight Construction and Low-Carbon Materials

SCG’s new walkway reflects the canal’s layered history, featuring a design inspired by the movement of water. Its sweeping geometry and folded contours form a sculptural structure that stands out against the dense urban surroundings, while the flowing surfaces interact with light and shadow. A steel handrail incorporates motifs drawn from the traditional Thai Kranok pattern, subtly connecting the contemporary design to the area’s cultural heritage.

The structure’s components were fabricated with LC3, a low-carbon concrete blend that substitutes part of the cement with calcined clay to significantly reduce environmental impact. The choice of clay-based material also recalls Ong Ang’s former role as a hub for pottery and ceramics. Each printed module was strengthened with high-performance concrete, enabling the bridge to support live loads of up to 500 kilograms per square meter.

Given the narrow, hard-to-access site, SCG manufactured all parts off-site. The bridge was assembled from 19 prefabricated units, each weighing around 1.5 tons, and installed in a single day using a compact crane, minimizing disruption for local residents.

Bridges and 3D Printing: Global Innovations in Concrete Infrastructure

SCG’s Ong Ang Canal bridge is part of a growing wave of experimental and sustainable 3D printed infrastructure around the world.

In Venice, Prof. Dr. Masoud Akbarzadeh of the University of Pennsylvania, in partnership with Swiss materials company Sika Group, has unveiled Diamanti, a 3D printed concrete bridge on display at the European Cultural Centre’s Time Space Existence exhibition from May to November 2025. Comprised of nine prefabricated segments printed with a robotic arm and a two-component cementitious mix, the bridge uses hollow and patterned geometries to reduce material use and embodied carbon. Its post-tensioned assembly with ungrouted steel cables avoids adhesives and grout, making the structure fully demountable and recyclable, while showcasing the potential of robotic printing to improve efficiency, adaptability, and sustainability in construction.

Similarly, Italy’s Polytechnic University of Bari has brought Leonardo da Vinci’s architectural vision into the modern era with its six-meter “Da Vinci’s Bridge” prototype. Led by Vincenzo Gurrado of the startup B&Y, the project uses a low-impact mortar made from waste stone powders and a lime-based binder, demonstrating how industrial byproducts can be repurposed for structural applications. Partnering with 3D printing specialist WASP, the team fabricated 13 modular blocks with a 3MT LDM Concrete printer and assembled them into a self-supporting arch using stereotomy techniques and temporary centering, eliminating the need for permanent formwork.

*This article originally appeared on [3dprintingindustry.]. [PALOMA DURAN] is the original author of this piece.