Application of Nanotechnology for Improving Cement Composition Properties
10th International Conference on Nanosciences & Nanotechnologies (NN13) 2013
Aleksandrs Korjakins, Genādijs Šahmenko, Diāna Bajāre, Jānis Justs

: Advanced properties of ultrahigh performance concrete (UHPC), such as high compressive strength, high modulus of elasticity, low permeability and excellent durability, can be achieved taking into account some basic principles and processing methods. Following tasks should be solved by reaching these properties: minimising defect occurrence in concrete matrix and obtaining maximum density by optimizing particle size distribution; minimising water/cement ratio by the use of water reducing admixtures and using pozzolanic materials. Improvement of microstructural packing and enhancing formation of secondary calcium silicate hydrate can be achieved by fill voids between larger particles. Since pozzolanic activity depends basically on content of amorphous silica dioxide, particle specific surface area and particle size distribution, different investigation and tests have been performed. Used silica dioxide particles have wide range of particle grading ranging from 20 nm to 100 m. Conventional non-modified concrete can be defined as a porous media with high capillary porosity, especially in the aggregate–hydrated cement paste transition zone. Two different ways to reach denser matrix have considered and implemented in the investigations. The first one is the applying of pressure to a fresh concrete with aim to reduce porosity and therefore improving concrete mechanical properties and durability. By applying pressure in initial phase of concrete hardening, increase of compressive strength in 1.5 times and decrease porosity in 4.5 times with effect of reducing capillary water have been reached. The second way is use special nano-sized particles synthesised by Sol-gel method, that characterised by extremely high specific surface area and very high pozzolanic reactivity. The properties of the fresh and hardened cement compositions have been tested in the framework of the research.


Keywords
High performance concrete, pressure application, compressive strength, sole-gel method, pozzolanic admixture

Korjakins, A., Šahmenko, G., Bajāre, D., Justs, J. Application of Nanotechnology for Improving Cement Composition Properties. In: 10th International Conference on Nanosciences & Nanotechnologies (NN13), Greece, Thessaloniki, 9-12 July, 2013. Thessaloniki: 2013, pp.212-212.

Publication language
English (en)
The Scientific Library of the Riga Technical University.
E-mail: uzzinas@rtu.lv; Phone: +371 28399196