As a wide variety of industries explore sustainable improvements, many look to options like process changes to improve efficiency while cutting resource uses. Those alterations can help, but it's sometimes necessary to do things differently regarding the materials used.

The construction industry is a prime example with its use of concrete. Cement is a binding material that mixes with sand, water and gravel to make concrete, the world's most widely used construction material. Portland cement—invented in the early 1800s—is part of the vast majority of concrete used today. The process of making it causes problems for the environment, however.

Issues With the Traditional Concrete-Making Process

Getting to the heart of why concrete creation needs sustainability improvements requires knowing the process for producing it. First, ground limestone and clay go into a rotating kiln and get heated to extremely hot temperatures. The heat causes the formation of a solid material called clinker that gets finely ground to produce cement.

A chemical reaction causes emissions from waste carbon dioxide. Plus, the fossil fuels for heating the kiln account for another sizeable segment. Additionally, emissions occur due to the mining and transportation associated with the raw materials in cement. Statistics indicate cement accounts for about 8% of global carbon dioxide emissions.

Low-Carbon Concrete as a Way Forward

Pioneering construction companies hope that altering production processes could have substantial impacts on the environment. One company engineered a new concrete that uses less limestone, plus reduces the heat of the kiln by 300 degrees Celsius. The enterprise also cures the cement differently by making it react with carbon dioxide that gets pumped in—rather than the usual method of water reacting with the cement.

Inventions also exist that use different ingredients to achieve sustainability goals. A recent project concerning highway repair in the United Kingdom cut carbon dioxide emissions by 77% after using an alternative concrete that does not contain Portland cement.

There's also a product from India called Navrattan Green Crete. It offers a pollution-free manufacturing process and is reportedly stronger than options made with Portland cement.

With so many choices emerging on the market, the conditions are ideal for companies that want to try a greener approach to construction. Government officials in Ottawa have even mandated that all federal construction projects in the city use a specific type of cement. It results in 10% fewer emissions than the standard kind, and construction companies must begin using it next year. Those authorities may also introduce emission limits associated with federal purchases of concrete.

Part of a Concentrated Effort

Low-carbon concrete shows promise, but decision-makers in the construction sector must realize it is not the only way to make positive changes. For example, statistics indicate that rentals account for 40% of construction equipment, and experts anticipate an increase in that percentage. If a company only needs a piece of equipment for a short time or the one they own is old and inefficient, renting makes sense both from an environmental and budgetary standpoint.

Researchers also recently examined an 8-kilometer stretch of highway to determine some of the most accessible and effective ways to cut emissions in construction. Using different ingredients in concrete was one of the recommended strategies. They also recommended recycling and reusing steel, asphalt and excavation masses. Optimization transport was on the priority list, too, as well as efforts to make materials more efficient and have enhanced designs.

Some construction companies work toward their sustainability milestones with autonomous machines. One robot patrols worksites and checks the progress against digital design files. That approach can give project managers early warnings of projects slipping behind schedule or those at risk of not meeting a client's expectations. These robots can also screen for safety violations, decreasing the chances of work assignments taking too long due to accidents.

Hope on the Horizon

The construction industry is not historically among the first to adopt new technologies. The statistics associated with the sector's contributions to carbon emissions are widely cited and well-known, however. A growing number of companies realize it's time to make positive, lasting changes. The good news is that technological advancements are helping that otherwise daunting goal come to pass. The construction sector could set an example for the world by pursuing progress.