Romanenko A. Very fast hardening without steaming concrete for manufacturing concrete sleepers without heat and humidity treatment

Object - the cement-water systems CWS, cement stone, concrete, reinforced concrete sleepers for railway tracks; goal - the development of very fast hardening concrete with superplasticizer additives and hardening accelerator for the production of concrete sleepers without heat and processing, and methods - study of physical and mechanical properties of the cement, concrete and ties carried out by standard methods and techniques of the original, the phase composition and structure of the cement stone - physico-chemical methods of X-ray diffraction, infrared spectroscopy, scanning electron microscopy, and electrical characteristics of the concrete sleepers - by the original method using standard measuring devices and specially designed sensors and systems ; the novelty - theoretical representation of the structure of the primary circuit and the frame and with the addition and withoutadding superplasticizer cement-water system CWS. Established that the formation of a strong primary frame CWS and achieve early strength concrete most suitable for selective adsorption of C3A and the ability to be integrated into the primary frame without disturbing its structure is the addition of superplasticizer C-3. Found that in the cement paste and concrete stone of very fast hardening concrete has not only the plasticizing and water-reducing, and structure-function, incorporating into the overall structure of the primary frame, and calcium chloride - not only accelerating, as well as structure-function, strengthening elektrogeterogen contacts. The composition of very fast hardening concrete without steaming with optimal values of coefficients gauging grains of sand and gravel mOPT aOPT, water-cement ratio (W / C) OPT = 0.32, the cost of additives, C-3 - 0.45% and a hardening accelerator calcium chloride 1% weight of cement, which provides transfer concrete strength 32 MPa in 12-16 hours curing at temperatures up to 30 ° C.