Researchers from Perm have developed a method that enhances the water resistance of concrete.

Concrete is the most widely used construction material. According to BusinesStat, its production in Russia increased by 10 percent in 2023, reaching 66.6 million cubic meters. Concrete is used to create building elements that endure significant loads, exposure to moisture, salts, and other external factors. Underground structures, foundations, and basement walls are in constant contact with water. Due to its porous structure, concrete readily absorbs moisture, which weakens it and leads to cracking. Additionally, when water freezes within the concrete, it expands, causing structural damage and compromising the integrity of the entire building. Researchers at Perm Polytechnic have discovered a solution to this issue by determining the optimal dosage of special additives that enhance the waterproofing properties of concrete.

2024-12-20 10:00:20https://naked-science.ru/article/column/razrabotka-permskih-uchen

The article was published in the journal "Modern Technologies in Construction: Theory and Practice." The research was conducted as part of the strategic academic leadership program "Priority 2030."

While surface waterproofing can be applied during construction, it either fails to protect the concrete from all sides or is too labor-intensive to apply. The most effective method is volumetric waterproofing of concrete through the use of modifying additives. These are introduced into the concrete mix during production to enhance its water resistance. Additionally, they improve other properties, such as workability, to ensure better filling of the required forms. These additives are referred to as plasticizers. High standards are set for their quality and effectiveness, as they must not only enhance the water resistance of the concrete but also not degrade its other characteristics.

Scientists from Perm Polytechnic University evaluated the effectiveness of a modern modifying additive designed to improve the water resistance of concrete. This additive is intended for materials used in the construction of foundations, swimming pools, and load-bearing structures of residential buildings. However, it was found that the material does not provide the desired workability, mobility, and property retention in the concrete.

The polytechnicians suggest using this additive alongside a superplasticizer— a substance that increases the plasticity of the material while reducing the water-cement ratio by approximately 30 percent.

“We tested cylinder samples of concrete using the 'wet spot' method: we placed them in a device with niches where water was directed through gradually increasing pressure. The experiment concluded when moisture began to appear on the surface of the samples, creating a wet spot. We evaluated the pressure at which this occurred and how deeply the water penetrated into the cylinder,” comments Alexandra Kiseleva, a student at the Department of Construction Engineering and Materials Science at PNIPU.

“The results showed that the optimal concrete composition is 1.5 percent superplasticizer by weight of cement and one percent of the studied modifying additive. This ratio of substances increases the water resistance of the material by two times while maintaining its structural strength, workability, and mobility necessary for concrete work,” explains Stepan Leontiev, an associate professor at the Department of Construction Engineering and Materials Science at PNIPU, candidate of technical sciences.

Scientists from Perm Polytechnic University have developed a concrete composition with additives that enhance the durability and reliability of products in the production of reinforced concrete structures, making them waterproof under the influence of groundwater and other aggressive factors.