Growing concern about the environment and climate change has led to a greater focus on sustainability in all areas of our lives.
Consequently, focusing on the construction sector, some studies estimate that approximately 30–40% of pollutant emissions are generated by the extraction of materials, manufacturing, transportation, installation, and the useful life of infrastructure.
In this context, it is important to discuss concrete, the most widely used material in construction. Since its emergence around 500 B.C., it has undergone changes to become the material we know today, consisting of a binder (usually Portland cement), aggregates, water, and various additives.
Therefore, below we will examine how the concrete industry is reducing its environmental impact by developing more sustainable concretes.
Types of Sustainable Concrete
As part of the current trend, in which the concrete industry is seeking to reduce its carbon footprint by optimizing construction processes that have a lower environmental impact or by using recycled materials, special types of concrete that are more environmentally friendly have been developed. Below, we will look at three types:
This type of concrete differs from conventional concrete in that a portion of the natural aggregates is replaced by recycled aggregates derived from construction and demolition waste, with regulations recommending that recycled aggregates not exceed 20% of the total aggregates in reinforced concrete structural elements and prohibiting their use in prestressed concrete, as they impair the material’s final properties.
Therefore, reducing the use of natural aggregates achieves two goals that lessen the environmental impact of their production: on the one hand, since fewer aggregates are needed, the energy consumed in their extraction and transportation is reduced; and on the other hand, pollution is reduced by reusing materials.
Its main characteristic is the ability of plant organisms to grow naturally on its surface. It is manufactured using both conventional cement and a magnesium phosphate-based cement, which facilitates setting.
This facilitates and accelerates the growth of organisms such as microalgae, fungi, and mosses, which are capable of absorbing CO2 from the environment, thereby reducing the environmental impact.
- Photocatalytic concrete
As in the previous case, photocatalytic concrete has a decontaminating effect in the area thanks to the addition of titanium oxide nanomaterials. Because of this property, photocatalytic concrete is specifically designed for use on exterior structures in urban areas with high pollution levels.
To reduce pollution, this semiconductor material harnesses the energy of sunlight and, upon contact with water, is able to return to its original state, ensuring that this decontaminating effect does not diminish. Furthermore, this effect is not affected by freeze-thaw cycles, the presence of salts, or exposure to ultraviolet radiation.
In conclusion, the construction industry in general—and the concrete sector in particular—has been taking the necessary steps in recent years to address the growing concern about pollution that we are currently facing.
If you want to advance your career in this field, we recommend our Master's Degree in Industrialized Concrete Construction—co-organized with Andece—so you can become a true expert.
