Can we pave the way toward sustainable concrete?

Construction is one of – if not the – oldest industries in the world. It’s changed significantly over time, and one of the ways it’s done so has been to introduce the usage of new sustainable processes and products. Concrete, the often-pollutive product made from cement and other raw materials, has historically been pollutive and, because of this, has been the subject of new eco-friendly efforts.

Creating sustainable concrete – or concrete alternatives, or any sustainable building material, really – that matches the qualities of existing options is tricky. It needs to be durable, strong, resistant to fire, economical – the list goes on. However, companies in the construction industry are making efforts to increase the environmental friendliness of everything surrounding concrete, including the raw components that make it up and the processes by which it’s produced and shipped. In the future, “sustainable concrete” might not sound so much like an oxymoron.

What is concrete, after all?

We often hear terms like concrete, cement, pavement and asphalt thrown around interchangeably, though they’re different things.

Concrete is made of cement, which is produced by heating a material – typically limestone and clay – to a very high temperature, creating a coarse material called clinker. The clinker is then ground to create Portland cement, which is seen as the industry standard. It also produces significant amounts of carbon emissions in the process, releasing nearly a pound of CO2 for every pound of cement made. The cement serves as a binder with water and other materials to create concrete, which is mixed and shipped around the world, heralded as one of the best building materials that exists. It’s durable, strong and long-lasting. As a “dirty” material in such high demand, it’s a ripe target for being made more sustainable.

Are there ways to make concrete sustainable?

The process for doing so starts – unsurprisingly – with cement.

While cement is the building block for concrete, it isn’t itself a naturally occurring material. It’s created by combining raw components which must be mined. Mining, like construction, is a necessary industry that’s currently undergoing a green revolution. Previous methods have proven problematic and are now being made more sustainable. At the helm of this shift is Grupo Argos, a Colombia cement and concrete producer that’s among South America’s largest conglomerates in the field.

Argos uses GEOVIA to design its mining operations, leveraging the tool’s virtual twin technology for optimized extraction scheduling and mine design. Doing so allows them to streamline these processes, cutting down on production time while implementing more efficient work that embraces the natural environment and reduces waste. By deploying the GEOVIA Geology solution, they’ve improved their business practices more efficiently than before, netting them 10% in savings on operational costs for specific processes, like crushing limestone.

“We are going to work not only in strategic planning but hand-in-hand with Dassault Systèmes in robust planning of our mines, adjusting and simulating all those changing scenarios of our environment to be able to inform the company to foresee risks and secure those raw materials to fulfill our final product,” said Javier Buitrago, mining projects manager for Grupo Argos.

Once the raw materials have been collected, they need to be combined and turned into cement, a process that requires heat, and a lot of it. The heating process emits significant amounts of CO2, so companies in this space are developing new technologies to identify methods to produce the necessary product without also producing harmful waste in the process. One method involves innovating the consumption and emission aspects of the kilns required to heat cement. Furno, a startup in this space, is producing kilns that are more efficient than traditional ones, reducing their emissions by upward of 70%. At the end of the day, it’s not a perfect solution, but one that aims to make a necessary process a little bit better for the environment.

Bit by bit, innovating each step of the process, from mining to firing up a kiln, the industries involved in cement production are embracing technological solutions for more sustainable results.

Why aren’t there concrete alternatives?

In other industries, when a significant component is identified as a high emitter of carbon or heat, it’s generally possible to create a more sustainable option. Take electric vehicles, for example. They achieve the same functionality as their gasoline-powered, combustion engine-outfitted counterparts. While their range might be less than some traditional vehicles, it’s safe to say they get the job done.

But concrete doesn’t really have a comparable solution.

“As of today, we can’t replace concrete as we know it,” explained Clement Pozzo, Infrastructure, Energy & Materials Industry Business Value Consultant here at Dassault Systèmes.

“We need it to achieve our infrastructure needs, but we need to do everything we can to ensure it’s being made as sustainably as possible,” he added.

Concrete is unique in its strength, durability, malleability, thermal conductivity – you name it. It achieves what other materials can’t, and at a competitive cost. The process of attempting to identify truly viable alternatives hasn’t produced any.

Some materials have shown promise in certain respects, but have fallen short in others. Hempcrete takes two to three times as long to produce as concrete does. Ashcrete is slow to develop maximum strength once set. Fiber cement uses some of the same carbon-emitting components that traditional cement does. Concrete derived from bamboo isn’t strong enough in the long term.

“What we need is a paradigm shift,” Pozzo added.

While concrete is necessary for some building projects, it doesn’t need to be the go-to for all of them.

“Where we don’t fundamentally need it – like low-rise buildings, roads, sidewalks and patios, we could tend towards using new and innovative materials. Chang Changing the way we design, build and live is definitely a challenge, but it’s the way forward,” Pozzo said.

The eco-friendly element of technology

Producing sustainable cement and concrete are two parts of the equation, but raw materials aren’t the end product in the construction industry – buildings are. It’s equally important to make both the necessary components like cement and concrete and the finished product of entire buildings more sustainable.

The solution then, comes from a variety of places. Greenifying the existing pieces of the puzzle to the extent that it’s possible to do, introducing new ways to make finished products more sustainable and identifying eco-friendly alternatives where applicable also represent approaches that can be taken.

Using virtual twins, companies have the power to leverage technology to ensure every aspect of the procurement, transportation and building processes are as green as the materials they’re using. Technological solutions that empower and enhance sustainable practices can be the building block of the construction lifecycle. Cement can be created more sustainably, concrete can be procured from responsible, eco-friendly producers and buildings can be designed and constructed with energy efficiency in mind.

Concrete will likely remain a go-to material in the construction industry for years to come, and efforts to make it more sustainable should be lauded. However, there’s another approach that’s being taken, too: instead of shunning its usage in buildings, they’re developing solutions that offset some of its effects. Smart Panel, for example, designs a “skin” for buildings that mimics the human body’s epidermis, enabling edifices to “breathe” and regulate temperature without relying on air conditioning, which emits significant carbon and heat.

The road to sustainable concrete is paved with trial and error, with innovation and advancement, and with a growing commitment to introducing eco-friendly practices at every step of the lifecycle. Companies can enact change slowly and effectively by embracing technological solutions to pressing problems like the carbon emissions from the cement production process. Considering how much of a large and profitable industry construction is, it’s possible that even small shifts in methods and means can have a massive impact.