Penn Develops Bone-Inspired Carbon-Absorbing Concrete

The world’s appetite for concrete is insatiable.

It forms the bedrock of our cities, the arteries of our transport networks, and the very foundations of modern life.

Yet, this ubiquitous material, prized for its strength, versatility, and affordability, casts a long, dark shadow over our planet.

Responsible for a staggering 8% of global greenhouse gas emissions, concrete represents a colossal environmental challenge. Learn more about the environmental impact of concrete.

For years, the industry has grappled with this paradox, searching for ways to reconcile its essential utility with its devastating ecological footprint.

Now, a groundbreaking project from the University of Pennsylvania offers a glimpse into a radically different future, one where our infrastructure doesn’t just stand strong, but actively breathes.

Enter Diamanti, a research initiative that marries cutting-edge material science with ancient biological wisdom.

Led by Associate Professor Masoud Akbarzadeh and his team at the University of Pennsylvania, the project isn’t merely tweaking existing concrete formulas; it’s reimagining its very structure and composition.

The core innovation lies in a two-pronged approach: a novel, carbon-absorbing concrete mixture and a revolutionary, material-saving design inspired by nature’s most efficient architectures – bones.

Akbarzadeh, director of the lab spearheading the project, speaks with an almost reverent appreciation for nature’s ingenuity.

“Through millions of years of evolution, nature has learned that you don’t need material everywhere,” he explains.

“If you take a cross section of a bone, you realize that bone is quite porous, but there are certain patterns within which the load is transferred.”

This profound insight forms the bedrock of Diamanti’s design.

By mimicking the intricate, lattice-like patterns found in certain porous bones – known as triply periodic minimal surface (TPMS) structures – the team has engineered a pedestrian bridge prototype that uses a remarkable 60% less material while retaining full mechanical strength.

But the brilliance doesn’t stop at structural efficiency.

This bone-inspired porosity also dramatically increases the surface area of the concrete.

Why does this matter?

Because concrete, in its natural state, does absorb some carbon dioxide over its lifetime – up to 30% of its production emissions, according to some research. Explore how the carbon-absorbing concrete works.

However, this absorption is largely limited to the surface exposed to air.

Diamanti’s increased surface area, coupled with its specially formulated concrete mixture, supercharges this natural process.

The enhanced concrete, developed by Dr. Shu Yang in the Material Science Department, incorporates diatomaceous earth (DE), a naturally porous, silica-rich material derived from fossilized algae. Learn about diatomaceous earth in concrete.

This biomineral creates microscopic “channels” within the concrete, allowing carbon dioxide to penetrate deeper, maximizing the reaction at a microscopic level.

The result? Diamanti’s concrete mixture absorbs an astonishing 142% more carbon dioxide than conventional mixes, with the increased surface area contributing an additional 30% to this absorption potential.

The manufacturing process itself is equally transformative.

Employing robotic 3D printing, the team can precisely create these complex, lattice-like geometries, a feat impossible with traditional construction methods. Read about how 3D printing is changing construction.

This not only enables the material-saving design but also offers significant operational efficiencies. Understand more about reducing carbon emissions in construction.

According to Akbarzadeh, 3D printing reduces construction time, material, and energy use by 25%.

Furthermore, the structural system drastically cuts the need for steel – another emissions-heavy material – by 80%, while simultaneously lowering construction costs by 25% to 30%.

This holistic approach means a significant reduction in greenhouse gas emissions across the entire construction lifecycle.

The larger context of concrete’s environmental impact reveals the urgency of such innovations. Explore the need for sustainable concrete solutions.

As Andrew Minson, director of concrete and sustainable construction at the Global Cement and Concrete Association, notes, concrete’s strength, durability, and safety are “fundamental to why it is used at the scale that it is globally.”

While the cement industry has made strides, reducing its carbon emissions by 25% per metric ton between 1990 and 2023, overall emissions have paradoxically risen since 2015 due to soaring demand.

The primary culprit is cement itself, accounting for about 90% of the sector’s emissions.

Its production involves an energy-intensive process of breaking down limestone at extremely high temperatures, which not only burns fossil fuels but also releases CO2 directly from the limestone as it decomposes.

Against this backdrop, Diamanti stands as a beacon of possibility, joining a growing chorus of innovative solutions.

Companies like Japan’s CO2-SUICOM and the UK’s Seratech are also exploring novel, carbon-absorbing concrete mixes, often incorporating minerals like olivine or alternative binders. Learn about alternative solutions.

However, Diamanti’s dual focus on both material and structural design offers a unique synergy.

As Du Hongjian, a senior civil engineering lecturer at the National University of Singapore, observes, even without the material innovation, the higher surface area alone allows for significantly greater CO2 absorption.

Yet, like all promising solutions, Diamanti faces practical considerations.

The diatomaceous earth (DE) that lends its unique properties to the concrete mixture had a global production of 2.6 million tons in 2023.

While potent, this supply chain must be carefully considered if DE is to meet the astronomical demands of the global concrete industry.

Both Hongjian and Minson acknowledge this potential limitation, suggesting that while DE may not be a “silver bullet,” it could provide a crucial “niche solution” where readily available.

Indeed, as Minson rightly points out, “There’s no silver bullet. We need to be doing all the different actions that we can to manage material demands and reduce carbon.” Explore various solutions to cut carbon emissions.

The journey from concept to reality for Diamanti has been robust.

After launching in 2022 with support from Swiss chemical company Sika and grants from the US Department of Energy, the team built a five-meter prototype to demonstrate feasibility, followed by a larger 10-meter version that passed load testing with “flying colors.”

This prototype is currently captivating audiences at the European Cultural Center in Venice for the Venice 2025 Architecture Biennial.

Although initial hopes of building the first full-scale bridge in Venice were thwarted by regulatory changes, the project has now secured approval to construct its inaugural real-world structure in France, with the exact location still under wraps.

Akbarzadeh is eager to see his designs tested in a live environment, where continuous monitoring will provide invaluable data.

Beyond bridges, the team envisions a broader application for Diamanti’s principles, exploring possibilities like prefabricated floor systems. Read about prefabricated sustainable construction.

While not a singular panacea for concrete’s complex environmental challenges, the Diamanti project undeniably opens “a whole new world of possibilities” for sustainable construction.

It’s a testament to human ingenuity, reminding us that sometimes, the most revolutionary ideas are found by simply looking to nature, and then having the audacity to build them.