Self-compacting concrete is a highly flowing concrete that compact under self-weight without any vibration effort. The mortar phase of self-compacting concrete determines its rheological, strength characteristics, and durability. This paper discusses the effect of superplasticizer and silica fume on the properties of self-compacting mortars. Mini-slump flow diameter tests were conducted to determine the rheological properties of mortar mixtures, and compressive strength, density, water absorption, porosity experiments to assess the hardened properties of mortar specimens. Analysis of regression models shows that the use of superplasticizer reduces the water demand of mortar mixtures by up to 40 %, and the addition of silica fume leads to the densification of cement stone structure and reduces the porosity of concrete to 24 %. The maximum compressive strength at 2 days can be achieved with a superplasticizer content of 0.8-1.0 % and 0-5 % silica fume by binder weight, and at 28 days – with 1.0-1.2 % superplasticizer and 10-15 % silica fume content. According to X-ray phase analysis in a cement stone containing superplasticizer and silica fume, the degree of cement hydration increases and reduces the amount of portlandite, which leads to an increase in the strength and durability of the concrete.

Development of the wrinkled fabrics depends on geometry and relaxation behavior of the multilayer woven fabrics. After bleaching and relaxation, the new shapes and sizes of crinkles were recorded. The results prove that the manner of fabric deformation during relaxation depends upon the multilayer fabrics structure. The quantities of the crinkles on the fabric are related to the float length type. Multilayer woven fabrics with longer float length show higher crinkled, and its deformation behavior is non-linear. Thus, connected deformations are closely related to the stretch potential and influence multilayer woven fabrics draping and fitting of the garment. For this purpose, we have postulated new model for the relationship between fabric geometry and stretch potential. The suggested hypotheses make it possible to predict mathematically the crinkle of multilayer woven fabrics and prediction of suitable-sett of warp and weft. The area covering value was chosen as suitable model for description of multilayer woven fabrics structure. The study was divided into two parts, the first presents the relationship between fabric geometry of the relaxation behavior whereas the second investigated the influence of multilayer woven fabrics stretch potential on the relaxation ability of bleached fabric. Three variants of cumulative parameter of a crinkle woven fabrics structure were introduced. The realistic models based on a better approach of geometry and material properties will be created in order to investigate the numerical analysis performance of the mechanical properties of crinkle woven fabrics. A correlation between calculated values of structural parameters crinkle multilayer woven fabrics values was evaluated.

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Self-compacting concrete is a highly flowing concrete that compact under self-weight without any vibration effort. The high workability of concrete mixtures is achieved by the reduction in coarse aggregate content while increasing fines aggregate volume. Usually, coarse quartz sands with fineness modulus more than 2.5 are used as fine aggregate. The use of low fineness modulus sands, characterized by high intergranular porosity and high specific surface area, as a fine aggregate, leads to an increase in the concrete mixture water demand and a decrease in its flowability. In such conditions, to obtain high-workability and high-strength concrete, increased cement consumption is required. The purpose of this study was to develop high-strength self-compacting concrete with reduced cement consumption and using low fineness modulus sand. To achieve this purpose, we optimized aggregates consumption in concrete composition, which achieves minimum aggregate mixture intergranular porosity, best concrete mixture workability without segregation, and maximum concrete strength. It has been established that silica fume and superplasticizer using allows obtaining high-strength self-compacting concrete of strength class B60 with low-quality fine sand and reduced cement consumption of 360 kg/m3. With increasing mixtures retention time before concrete placing, there was an insignificant increase in the flowability of obtained self-compacting concrete mixture and an improvement in the physical and mechanical properties of concrete. Remixing of concrete mixtures and concrete placing after 90 minutes from concrete mix preparation moment allowed to increase concrete strength to 17%, increase its density to 15 kg/m3, and reduce porosity to 25%.