Applied Mechanics and Materials Vols. 725-726

Abstract: There are supplements that could accelerate or slow down the process of setting and formation of the cement stone structure. After examining the effect of these particles, we can predict how they could influence on the growth of concrete strength. It is possible to assess the effect of supplementation activity using the thermo-kinetic method by exothermic effect, which is obtained by wetting and hydration of cement. A calorimetric research of the effect of cement-carbon material was held in this article.

Abstract: The article deals with issues of the thermal cracking resistance in massive concrete and reinforced concrete structures during the building period. The paper lists the calculation results of the NPP reactor foundation mat thermal stressed state and thermal cracking resistance. The research also considers the concrete hardening temperature influence on its thermo-physical and deformation characteristics. The deformation criterion is used to calculate the concrete thermal cracking resistance. In addition, the paper focuses on the assignment of safe concrete pouring technological parameters in the winter period. Furthermore, the article estimates the necessity of the structure peripheral electric heating during the building period.

Abstract: Wiliness to expand cooperation with European scientists has been triggered by profound study of European standards and codes. Having learnt European standards will make it possible to break technical trade barriers down and make it possible to have common-used design rules for buildings and structures. It is essential to start learning entire array of supporting documents. First of all standards for materials and standards for testing methods should be analyzed. This article deals with research of the European standard technical documentation in terms of specifications and testing methods for concrete mixes and concretes to be compared with the Russian standards.

Abstract: The influence of a shrink-resistant “Estrifan Additive RCL” additives on the cement paste shrinkage was researched. The cement paste shrinkage is reduced when we use this additive. When the content of additives is more than 2 % there is expansion in the initial stage of hardening. The extension period is longer and the value of expansion deformation is higher, the additive dosage is higher. The presence of superplasticizer Muraplast FК48 enhances the initial expansion effect and shrinkage decrease by reducing the rate of evaporation of water. On the contrary, in a separate action superplasticizer increases the cement paste shrinkage.

Abstract: Ventilated facades are widely used in modern energy efficient building, and it leads to topical issue whether it is important or not to stick to assembling terms of such kinds of facades. The first thing to do during the ventilated facades installation is to built in the mineral-cotton insulant which will be later protected by vapor proof material. Thus, the shield obtained on the exterior side of the building in the aggregate with ventilated clearance and facing material form a system with high insulation and resistant to environmental attacks. This article observed a situation in which the terms of ventilated facades installation were broken after the primary stage (not more than 90 days). The works were stopped for 1.5 year after fixing the heat-insulation material to the inclosing walls of the building. As a result, insulants were exposed to significant temperature and humidity changes, wind forces and UV rays. The main objective of this research is to determine the suitability of insulating material for further use taking into account changes in its basic parameters, which are determined by laboratory tests.

Abstract: In this article the effect of plasticizing and siliceous additives on the fluidity of the concrete mix and strength of concrete is investigated. Additives: superplasticizer S-3, fused microsilica FMS-85, hyperplasticizer PENTAFLOW AC 2, and a mixture of hyperplasticizer and microsilica CM 02-10 (10% MS and 0.2% HP)​​. In this paper presented results of tests of samples aged 3, 7 and 28 days.

Abstract: The article introduces the results of the experimental research and analytical expressions used to describe the dependence of strength, modulus of elasticity and ultimate strain of concrete on the level of long-term precompression at elevated temperatures up to 200°C.

Abstract: The features of the application of FRP reinforcement for concrete reinforcement. The results of mechanical tests. Shows the influence of the proportion of glass reinforcement on the physico-mechanical properties of rod fiberglass reinforcement.

Abstract: Are considered fireproof fiber-vermiculite-concrete composites with application of a portland cement, swollen vermiculite, volcanic ash, quicklime, plaster, a basalt fiber and saponified resin. Results of researches of composition and physicomechanical properties of fiber-vermiculite-concrete composites, experimental tests and theoretical researches of fire resistance two-layer reinforced cement elements are given

Abstract: Presented are the results of the research on the impact of such factors as temperature conditions and cement phase composition on the effectiveness of hardening accelerators for concrete and other cement systems. The evaluation of the modifying elements effect has been performed by using the isothermal calorimetry method. This research revealed the selectivity of the admixtures impact when used together with different cement brands, as well as the possibility of increase setting time for cement systems in lower temperature conditions with the addition of Lithium carbonate based accelerator.