Successfully fabricating super-strong concrete materials thanks to nanotechnology

The new concrete model has improved 75% in waterproofing and 44% in reducing the corrosive effects of salt compared to commercial versions.

Researchers at Washington State University (USA) have just succeeded in creating a "super durable" concrete that is extremely resistant to moisture and salt - two factors considered the most harmful to human health. this type of material.

Comparison of a concrete sample coated with a nano-modified joint sealant (left) and untreated concrete

According to Xianming Shi, a professor at the Institute of Civil and Environmental Engineering, who led the work, concrete - although it looks like solid rock - is still essentially a "sponge" to the eye. it's under the microscope. "It's a heterogeneous, highly porous composite material," says Prof. Shi emphasized.

So in their study, the researchers added two nanomaterials, graphene oxide and montmorillonite nanoclay, to a siliconate-based sealant. They then mixed the mixture into the cement, to create a concrete structure that would last as it hardens.

According to GS. Shi, these nanomaterials contribute to the thickening of the microstructure of concrete, making it harder for water and liquids in general to penetrate. They also form a barrier against the penetration of water vapor and other gases that tend to attack and erode the structure of the concrete.

Nanomaterials also protect concrete from the physical and chemical attack of desalination salts. The penetrating sealer is designed to be multifunctional, as it can also act as a curing aid for fresh concrete.

Field studies show that the new concrete sample has improved 75% in waterproofing and 44% in reducing the corrosive effects of salt compared to commercial versions.

Reportedly, much of the nation's critical infrastructure, such as the US highway system, was built between the 1950s and the 1970s and is now nearing the end of the life it was designed for. .

Statistically, every four years since the late 1990s, the Society of Civil Engineers in the US has provided a report on the country's infrastructure, consistently showing poor or failing grades. . Specifically, about 8% of the roughly 600,000 bridges in the US are considered structurally deficient, and one in every 5 miles (about 8km) of highways is in poor condition.

The problem is exacerbated in cold climates by multiple freeze/thaw cycles, as well as from the increasing use of deicer salt in recent decades by humans, which can cause Decomposition of concrete structures.

The new work can be seen as an effective complementary measure to address the challenge of weathering older bridges and pavements in the United States, as well as in many other countries around the world.

Currently GS. Shi and graduate student Zhipeng Li published their work in the Journal of Building Engineering Materials and applied for a provisional patent.