Use of waste production of crystalline silicon in the production of vacuum insulation

The purpose of the study is to consider the possibility of using microsilica - waste of aluminum production, as filler in a vacuum insulation panel. The properties of silicon dioxide powder have been studied, and compositions and manufacturing technology of vacuum thermal insulation panels on its base have been developed. Differential thermal analysis of powders is carried out; the curves of differential thermal analysis and thermogravimetric analysis, x-ray phase analysis are obtained. The microstructure of the samples is investigated. The thermal conductivity of the manufactured panels is measured. The test results suggest that for the manufacture of low-vacuum insulation panels of microsilica powders, waste production of crystalline silicon can be used. The use of waste in the future can become the basis for the production of high-quality vacuum insulation with low cost

Energy-Saving Technologies in Design and Construction of Residential Buildings and Industrial Facilities in the Far North

The article discusses the main problems of energy saving and special features of design, construction and operation of residential buildings and industrial structures in extreme climatic conditions of the Northern territories. The impact of permafrost, seasonal thawing of soils and low bearing capacity of thawed soils on the choice of ways of arrangement of cities and pipelines in the Northern regions of Russia have been analyzed. There have been assessed the effect of climate change and the associated natural and man-made risks in the Far North on the development of a system of measures to ensure the reliability of energy facilities and options for emergency response. The solutions allowing to increase energy-saving capabilities of buildings and to reduce expenditures at their operation have been designated. Necessity of using non-traditional and renewable energy sources has been considered. Document type: Part of book or chapter of boo

Особенности расчета трапециевидных совмещенных ребристых плит на деревянном каркасе

The article describes the features of design and calculation of ribbed slabs on wooden frame with trapezoidal plan, where the cover is included in the general work of the structure on operational loads. The field of possible application of the investigated elements is shown. The features of trapezoidal slab design are described. The main provisions of the proposed method of the considered structures class calculation are reflected. The formula dependencies of trapezoidal slabs calculation on deformations have been determined due to the use of the calculation method of structures that consist of different module materials; the outcomes of previous numerical studies carried out by the authors of the paper as well as the algorithms of a numerical functions determination based on a particular integral method. The location of a weak slab section when calculating on a normal stress has been defined with the regard to a part of an operating cover, which varies along the span length. It is shown that the proposed method allows to assess adequately the stress-deformed state of trapezoidal slabs and to calculate them on strength and rigidity according to the suggested algorithmВ статье рассмотрены особенности конструирования и расчета ребристых плит на деревянном каркасе с трапециевидным планом, у которых обшивка включена в общую работу конструкции на восприятие эксплуатационных нагрузок. Показана область возможного применения исследуемых элементов. Описаны особенности конструкции трапециевидных плит. Отражены основные положения предлагаемой методики расчета рассматриваемого класса конструкций. С применением метода расчета конструкций, состоящих из разномодульных материалов, результатов ранее проведенных авторами статьи численных исследований, а также алгоритмов численного определения функций на основе методики определенного интеграла, установлены формульные зависимости расчета трапециевидных плит по деформациям. Местоположение опасного сечения плиты при расчете по нормальным напряжениям вычислено с учетом доли работающей обшивки, которая изменяется по длине пролета. Показано, что предложенная методика позволяет адекватно оценивать напряженно- деформированное состояние трапециевидных плит и производить их расчет на прочность и жесткость по предложенному алгоритм

THE CALCULATION OF WOODEN CONSTRUCTIONS TAKING INTO ACCOUNT THE CREEP OF WOOD ON THE EXAMPLE OF A STATICALLY INDETERMINATE LENTICULAR BLOCKED TRUSS

Objectives The aim of the study is to refine the calculation of wooden constructions, in particular, to use variable elastic modulus  for the calculation of the second group of the limiting state in order to predict the deformations more accurately.Methods The study is carried out using the method of creep  consideration based on the use of either variable elastic modulus or  the “modulus of total deformations” for the calculations. These  moduli, besides the elastic, account for residual deformations, while  the fraction of the latter increases with increasing stress levels in the wooden elements.Results The calculation of statically indeterminate spatial timber-metallic lenticular block-truss loaded with a uniformly distributed  load is carried out. At the first stage, the construction was calculated using the elastic modulus of all wooden elements E =  10000 MPa in accordance with the set of rules (SP 64.13330.2011  (updated version of SNiP II-25-80). At the second stage, the elastic  modulus was replaced by variable, i.e., matched to the level of  stresses in the elements by means of interpolation. The obtained  deflection values are analysed and compared to the construction  limiting value. The study was conducted without taking into account the flexibility of node connections and defects of the wood, which  can also have a significant effect on the deflection value.Conclusion The use of a variable elastic modulus for calculations  significantly influences the magnitude of deformations (in our case,  deflections are increased by 30%). The study confirms the need to  take into account the creep of wood and refine the calculations of  wooden structures. Such approximating dependence at different moisture levels of wood will allow the calculation of wooden  structures to be performed at a higher theoretical level

Подходы к нордификации высокоширотного строительства

The simple mechanical transfer of structural technologies to high-latitude construction engineering is not efficient. But construction engineering nordifikation seems to be effective and expedient, for example working camps. Severe, extreme conditions in the Arctic are similar to extraterrestrial, for example, Martian therefore use of space technologies is required here. From this point of view, it is expedient to build space frame constructions such as: domes, lenses, spheres, Rello’s cones united by the covered transitions of ribbed type or the common covering, having good aerodynamics. In this article is emphasized the rationality of designs made of timber itself and wood materials that defines need of creation of the glued elements industry, that is possible only in presence of government supportПростой механический перенос строительных технологий в высокоширотное строительство неэффективен. Целесообразна нордификация строительства, например вахтовых поселков. Суровые, экстремальные условия в Арктике подобны внеземным, поэтому здесь требуется применение космических технологий. Целесообразно возведение зданий в виде пространственных сооружений: куполов, линз, сфер, конусов Релло, объединенных крытыми переходами нервюрного типа или общим покрытием, обладающих хорошей аэродинамикой. Подчеркивается рациональность конструкций из дерева и древесных материалов, что определяет необходимость создания индустрии клееных элементов, а это возможно только при наличии государственной поддержк