Study of properties of cements and concrete mixtures with carbon nanotubes

Abstract

The development of nanotechnology contributes to the production of a new generation of multifunctional building materials. Carbon nanotubes (CNTs) are one of the components that make it possible to obtain such materials. CNTs are so small that they are prone to aggregation. To exclude this phenomenon, it is necessary to subject the particles to ultrasonic dispersion and stabilization. The purpose of the study was determined, which is to stabilize CNT suspensions and study of the properties of cements and concrete mixtures containing stabilized CNT particles in their composition. During the research, we have established the optimal dispersion parameters (t = 25±2 °C, υ = 44 kHz, τ<30 min) and the stabilizer concentration (5 g/l). The tests on the compressive strength of modified cement samples showed that the complex additive, which includes polycarboxylates and CNTs, gives the maximum increase in strength in the first day by 60%, in 28 days - by 20%. The introduction of CNTs into the composition of the concrete mix increased the compressive strength by 32% on the 3rd day of hardening, and by 34-39% on the 28th day compared to the control composition without additives.