Building sand sculptures by the water’s edge is a rite of childhood — one that I loved to partake of. On many beaches around the world, you’ll find professional (and highly-skilled amateur) sculptors designing elaborate and stunning edifices. But, no matter the age or skill level involved, each sand creation is eventually reclaimed by the incessant waves of the ocean.
Now a group from the Institute for Advanced Architecture of Catalonia has found a way for those sand constructions to become permanent by using a 3D printer they’ve dubbed the Stone Spray Robot. The Stone Spray method employs soil (in this case, sand) as a base material and a liquid binder to adhere the granules together. When the mixture comes in contact with air, it solidifies to make sculptural forms.
The research project by Anna Kulik, Inder Shergill, and Petr Novikov focused on finding eco-friendly and innovative methods to use 3D print architecture in the future. For example, the team envisions using this technology to build shelters in areas which have suffered a disaster, since there would be no need to transport the actual building materials — just robots and binder.

Anna Kulik led the research project from the beaches of Barcelona, Spain.
The team spent some time perfecting the concept. As reported by Discovery News:
With help from Institute supervisors Jordi Portell and Miquel Lloveras, the group tackled technical challenges from nozzle design to the ideal additive. Using a prototype that only cost less than $200, they landed on a mixture of dry sand and a small amount of binding agent. One liter of the agent can solidify 35 cubic feet of dirt.
Although the exact recipe is proprietary, Novikov said it’s essentially a combination of acrylic and ethylene acrylic rubber, often used on country roads.
When hooked up to a set of solar panels and controlled with CAD software, the multi-directional robot successfully deposited the mixture into Gaudí-like sculptures. Dry sand helped the structures cure quickly.
Once completed, the sculptures were so strong that they didn’t break when hit with a baseball bat, Novikov said. Next the team plans to make the nozzle more precise and incorporate solar power directly into the bot. They want to spray larger architectural structures, including bridges.
What I find fascinating about the project is the organic quality that finished pieces retain. As opposed to the clean, perfected forms of 3D structures printed with Contour Crafting, Stone Spray objects have more natural variation in surface texture. They remind me of Frank Lloyd Wright’s experiments with concrete experiments in many of his later projects in the Southwestern United States.
Stone Spray is a excellent first step into ecologically-minded 3D printing. It will be fascinating when they work out the logistics to create larger structures.



















