Mechanoactivation of Portland cement in the technology of manufacturing the selfcompacting concrete
Journal Title: Восточно-Европейский журнал передовых технологий - Year 2018, Vol 3, Issue 6
Abstract
<p>This paper examines the intensive separation technology for producing a self-compacting concrete (SCC). We substantiate the proposed technology of SCC production through the effective control over viscosity of cement-water compositions, which to a large extent ensure the mobility of concrete mixes. A separate preparation of cement-water compositions at a high-speed mixer with its subsequent mixing with fillers in a regular concrete mixer profoundly changes the priorities in the production technology of a concrete mix. We substantiate the idea on that the use of the separation technology could optimize the modes of high-speed mixing in order to separately prepare the highly concentrated cement-containing suspensions under conditions of intensive hydrodynamic impacts on them. Particular attention is paid to studying the effect of content of the superplasticizer of polycarboxylate type Relaxol-Super PC, microsilica, and polypropylene fibers, on effective viscosity of the cement-containing suspension. Comparative analysis of influence of the original formulation factors on its value is described. It was found that the mechanoactivation of a cement-containing suspension in the presence of the admixture Relaxol-Super PC leads to the complete destruction of its original structure, which is necessary for the uniform distribution of microsilica and polypropylene fibers in the volume.</p><p>We describe the features of grain composition, rendering exclusive fluidity to the concrete mix, as well as the possibility of laying it in the mold without vibration. The intensive separation technology makes it possible to obtain SCC with the F4, F5 grades for fluidity, and compressive strength at the age of 28 days not less than 55 MPa.</p>We have scientifically substantiated and experimentally confirmed the effectiveness of mechanical activation for the separation technology of self-compacting concrete mixes and the high-strength concretes based on them.
Authors and Affiliations
Ivan Barabash, Darya Harashchenko
Assessment and prevention of the propagation of carbon monoxide over a working area at arc welding
<p>This paper reports a study of air environment at industrial premises where welding processes take place, with special attention paid to the formation of carbon monoxide (oxide) (CO) in the working environment in the p...
Theoretical and experimental assessments of accuracy of nonorthogonal mems sensor arrays
<p class="a">The paper deals with theoretical and practical assessments of nonorthogonal configurations of MEMS sensors based on both the uniaxial gyroscopes and the triaxial inertial measuring units. The main goal of th...
Researching the interaction of different printed materials types with liquids
<p>The interaction of papers and films with the testing liquid was researched. Measurements of the contact angle were taken depending on the substrate and its morphology. Linear dimensions of the paper were determined wh...
Selection of new working fluids for a heat-using compression refrigerating machine with the block «turbine- compressor»
<p>The compression heat-using refrigerating machines operating in the Chistiakov-Plotnikov cycle use recycled waste heat of power machines as primary energy for producing cold of various temperature potentials thus savin...
Determining the electromagnetic field parameters to kill flies at livestock facilities
<p>We have considered the electromagnetic method to kill the larvae of flies ‒ agricultural pests. To address the task, a problem on the distribution of electromagnetic fields in their body was solved. The solution is ba...