POZZOLANIC ADDITIVES FOR PORTLAND CEMENT FOR TRANSPORTATION CONSTRUCTION

Production of Portland cement is one of the most energy intensive among building materials, it is accompanied by significant CO2 emissions: 0,7 to 1 ton per 1 ton of cement, depending on manufacturing technology. Therefore, replacement of Portland cement clinker with active mineral additives of natural or synthetic origin is environmentally and economically viable, while not causing significant adverse changes in the properties of cement binders. A comprehensive analysis of the properties and research of the microstructure of Portland cement composition containing 20% of granulated blast furnace slag and 10% of pozzolanic mineral additives (zeolite or perlite) was carried out and their characteristics were compared with traditional Portland cement – CEM I, CEM II/A-S, CEM II/B-S. It was determined that the complex structure modification by additives of hydraulic and pozzolanic activity will improve technical properties of building mixes on the basis of such cements without significantly reducing their strength characteristics. It was established, that the introduction of pozzolanic additives in combination with granulated blast furnance slag leads to a change in the hydration mechanism of binding systemso that the resulting activity of composition increases the and not subject to the law of additivity.

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