Vol 8, No 1 (2018)

Theoretical studies of reinforced concrete eccentrically compressed columns of circular cross-section on strength indexes are analyzed. These studies rely on the use of a nonlinear deformation model that approximates the work of concrete to real experimental conditions. A comparative analysis of the results of calculating the strength of reinforced concrete columns of circular cross-section is carried out according to the methodology proposed in the current set of rules, is the author’s program for determining the stress-strain state of a reinforced concrete column of circular cross-section implemented in the MathCad software environment. The results of a numerical experiment are compared in the form of a fi nite-element model in the Lira-CAD program complex using a nonlinear deformation model. Calculations and schemes are given taking into account the possibility of conducting an experimental study.

The advantages of monolithic concrete and reinforced concrete in comparison with traditional technologies are considered. The evaluation of the structure of construction technology is given. The analysis of the main methods of winter concreting with the development of the structure of heating and non-heating methods is given. The main methods of maintaining concrete and reinforced concrete at negative ambient temperatures are described. An algorithm for estimating the methods of winter concreting for technical and economic indicators is developed: labor costs and electricity consumption. Prospects for the development taking into account the technical and economic eff ectiveness of the option of combining non-heating and heating methods for further investigation are outlined.

The technology of the device of certain anti-dump structures for the sections of mountain roads subject to collapses is considered. A comprehensive analysis of rockfall risk factors has been identifi ed and justifi ed in order to select the most eff ective protection system. The measures on passive protection (catching structures and devices, anti-galleries galleries, simple drapery systems) and active protection (restraining structures and drapery systems with additional reinforcement) have been analyzed. The materials used in advanced anti- dump systems are distinguished, they are characterized by increased strength, enhanced corrosion protection, relatively low weight, which makes it possible to use light technology.

The results of complex studies of the parameters of the heat-conducting collectors, development of the methods for their calculation are presented. The main diffi culty in this case is the calculation of the design and parameters in the region of the contact zone between the heat pipe and the heat-generating surface. It is shown that the calculation methods used for convective collectors can not be applied to collectors with heat pipes in which the elements do not depend on each other. It is established that semiempirical models provide an opportunity to study the specifi cs of the processes taking place in the reservoir, the degree of their infl uence on its effi ciency. The simplifi ed calculation technique proposed in this article allows us to make the required estimates and calculations at the engineering level.

The article is devoted to the study of the infl uence of microwave electromagnetic radiation (UHF EMP) on the properties of sewage sludge. The possibility of using microwave radiation for their processing is shown. The results of experiments confi rming the positive eff ect of the process under study on the degree and speed of compaction of a mixture of precipitation and activated sludge, improvement of their moisture yield, an increase in the yield of heavy metal impurities in decanted water, a decrease in the specifi c resistance of fi ltration and capillary suction of the sediment, precipitation. A hypothesis is proposed for the eff ect of UHF EMP on wastewater sludge.

The causes of critical situations in sewage treatment plants for municipal water disposal are analyzed. A survey of local treatment facilities of the microdistrict in a critical failure situation was carried out and problems were identifi ed, caused by the discharge of either under-treated or completely untreated sewage into the reservoir. To restore the functioning of treatment facilities an optimal technological regime has been developed, taking into account changes in air supply, introduction of biologics, addition of hydrogen peroxide and the use of LEDs in the aerobic part of structures.

Technological processes are considered and the industries that are the source of cadmium entering the environment are identifi ed. The materials, raw materials and technologies promoting pollution of air with Cd-containing emissions are determined. The ways of gett ing cadmium into the human body are considered. The negative consequences of accumulation of heavy metal in the human body are estimated. The method of atomic absorption spectroscopy was used to study food products for the content of cadmium in them. Studies allow to regard cadmium as a super-toxicant of the environment due to its widespread prevalence and extreme danger. The measures of a technical and medico-prophylactic nature to limit the effects of cadmium on humans are proposed.

The urgency of preservation and adaptive use of historical buildings and structures is considered. As a key idea, a position is formulated on the most important role of industrial enterprises in the history of the formation of the city of Samara, the importance of these buildings as valuable heritage objects and the need for their preservation and development. Foreign analogues are considered on the basis of which the principles and methods of architectural solutions of the adaptation of historic buildings and complexes for modern use are revealed. It is concluded that in the cities of Russia, including Samara, there are many objects that need to be preserved, restored and reused. The accumulated foreign experience can help in drawing up a theoretical and practical basis for preserving the heritage.

Taking into account the historical context the characteristic features of the Novgorod architectural school of Orthodox temple architecture of the 12th-15th centuries are explored. A comparative analysis of the most signifi cant objects of this period is carried out. The process of formation of the Novgorod style is traced. The volume-spatial and architectural-artistic features of a number of buildings are listed and described. A conclusion is drawn about authentic elements and expressive methods characteristic of this direction.

The specifi cs of the evolution of perception of the value of historical architecture in the formats of time, form and context are revealed. The place and character of the history of architecture relative to the general history of mankind and the history of other types of society activity is determined. The substantiation of the value fi elds of historical architecture in time, form and context formats is provided with the identifi cation of the specifi cs of their integrated assessment in order to determine the prospects for the existence of a historical architecture. The defi nition of the physical and metaphysical contextuality of the historical architecture is given taking into account its bifunctional essence. Typical predictive assessments of the prospects for the existence of historical architecture are given.

The article tells about the semantics of carved ornaments of ancient wooden houses in the city of Samara and explores the ornamental features of the wooden and stone-wooden buildings of the city, built in the late 19th century. Relying on the studies of historians who studied the culture of Ancient Rus, the authors show that the semantics of the wooden carving of the city of Samara is closely related to the pagan beliefs of the ancient Slavs and the folk traditions of applied art and craft. The authors cite the classifi cation of the main parts and elements of buildings decorated with house carvings, emphasizing the connection between the ornament and its location on the houses in accordance with the model of the pagan universe and the magical-spellcasting rites of the ancient pagans. The article analyzes the existing types of house carvings in the city, illustrates the construction of traditional ornamental composition, the geography of thematic infl uences and traditional crafts. At the same time, a conclusion is drawn about the high variety of compositions and the uniqueness of the Samara wooden carving of each old house.

The purpose of the article is to identify the infl uence of the system of priority identifi ers on the architecture of public objects in Samara in the historical stages, from the time of the foundation of the city (1586) to the present time. On the example of some heritage objects the diff erence between the architectural and historical environment and its uniqueness is shown. The conclusion is made that the preservation of the identity of the place is the most important principle of sustainable development of the architectural and historical environment, since the historical and cultural heritage must be transferred to the future. As a result, the image of the Samara residential development along the whole path of its development was determined, the types, styles, impacts of the external and internal ethnos, as well as the productive forces that are the basis for the development of the city in each historical period.

A technique for modeling the magnetic fi elds of power transformers in the environment of the software product FEMM 4.2 is developed taking into account the design scheme and real geometric dimensions of the magnetic system and tank, quasi-permanent current components in high-voltage windings, and the experimental magnetization characteristics of electrical and structural steel. Modeling of magnetic fi elds of magnetic systems of rod and armored rod structures is carried out on the example of serial power transformers TRDN- 63000/115 / 6.3 / 6.3 and TDTs-400000/242/20. The dependences of the mean values of induction in the central cross sections of the rods and side yokes on the quasi-constant currents are determined. It is shown that the saturation of the magnetic system of the rod structure begins with the outer rods at a multiplicity of quasi-constant current equal to 2.2 relative to the nominal phase current of the high-voltage winding. The saturation of the magnetic system of the armored rod structure begins with the lateral yokes at a multiplicity of the quasi-constant current equal to 2.63 with respect to the idle current rating.

The analysis of the operation of precision pairs is given in the presence of distortions and misalignments between the plunger and the cage. The fl ow of a viscous incompressible fl uid during the pulsation of the pressure drop and the oscillation of the plunger by periodic arbitrary laws in annular gap gaps with a variable eccentricity along the channel length is considered. A plane channel fi lled with a viscous incompressible fl uid with an angle of inclination of the upper wall to the lower one is considered. The upper wall performs arbitrary periodic motions in its plane, the pressure diff erence at the ends of the channel also varies according to an arbitrary periodic law, but with some other period. The problem is solved in the polar coordinate system. Since the boundary-value problem does not have an exact analytic derivation, an approximate analytic solution is found