We have reviewed the methodology on a specific example of greenhouses of type 6D, the calculation of the bearing capacity of the upper and bottom zones roof trusses. The urgent need for in-depth analysis of the issue bearing capacity appeared in the light of a rather massive construction of greenhouses, especially in the Southern Federal District, as its constructive is purchased in the Middle East. However, the simple transfer of designs greenhouses made in the Middle East, to the territory of the Russian Federation is not completed successfully. These structures cannot withstand greenhouses in some cases, according to the service manual, snow loads, in other cases, wind loads, and in the third case, the construct may be destroyed for no apparent reason. Need to clarify the situation become clearer. Successive static, dynamic and seismic analysis carried out by force in the territory of the Russian Federation regulations and norms provider in relation to the actual sections bearing structural elements, revealed The following percentages of use of structural elements under consideration. According to the standards of the Russian Federation, for the first limit of the percentage of use - 395%; the second limit of the percentage of use - 999%; according to the norms of the Russian Federation with the load provider for the first limit of the percentage of use - 339.3%; the second limit of the percentage of use - 999%. The upper chord coating: according to the standards of the Russian Federation, for the first limit of the percentage of use - 495.2%; the second limit of the percentage of use - 361.4%; according to the norms of the Russian Federation with the load provider for the first limit of the percentage of use - 150.8%; the second limit of the percentage of use - 146.2%. The analysis presented allows us to conclude that when uploading the upper and lower zones of farms covering greenhouses, load combinations specific to the location of the greenhouse type 6D, their carrying capacity and hence the structure as a whole is not guaranteed
The article deals with the calculation of basic parameters of making bulk materials on the surface of the field. This calculation makes it possible to obtain data on the required amount of particulate matter
We have presented a comprehensive calculation of chain drive with internal teeth, comprising: geometric calculations, power and dynamic parameters of the transmission, as well as a method for fabricating the sprocket with internal teeth and wear prediction model of roller chain
In the article the presented questions of theoretical research of processes of an electric resonance of the generator of ozone were discussed and their influence on productivity and electro-ozonizer efficiency was also defined
This article discusses the basic analytical expressions for the calculation of power generators and select features basic functional units of wind turbines, allowing the design phase to conduct a preliminary assessment of the effectiveness of wind power stations, which supplies specific consumers of electric power
The technique of determining earthen channel hydraulic parameters using the solutions of differential equations describing the steady non-uniform flow of water in open channels with variable flow is shown
Considerable parts of the ablation zones of mountain
glaciers in various mountain systems of the World are
covered with rocks (dibris). Heat and physical
properties of debris layer are very different from those
of ice. Debris layer determines ablation rate and ice
run-off regime. Dependently on thickness, it can
accelerate ablation or totally isolate ice cover from
melting. To describe ablation rate in a mathematical
model correctly, one needs to include in it a block
responsible for heat exchange of debris-covered areas
with the atmosphere. In the paper, we consider an
algorithm for calculation of ablation rate under the
layer of debris, which is to be incorporated to the
surface mass balance model. We also describe results
of calculations of temperature distribution in a debris
layer and estimates of ablation rate under the latter. All
calculations were carried out for heat and physical
properties of Djankuat Glacier in the Central Caucasus
The article presents a calculation of traction resistance chisel working organ for layered subsurface soil treatment and proposed the construction of a working body for subsurface tillage with an elliptical element. We have also included a comparative analysis of traction resistance of workers to the waterline and moldboard tillage
A method is considered, on the concrete example of hothouses of type of 6D, for calculation of bearing strength of overhead and lower belts of farms of coverage. The vital necessity of deep analysis of the question of bearing strength appeared in the light of satisfied mass erection of hothouses constructions of which are bought in the countries of Near East. However, a simple transfer of constructions of hothouses made in the countries of Near East can not be successful on the territory of the Russian Federation. These constructions of hothouses can not be maintained in some conditions, according to service exploitation, like snow loadings, in other cases - wind loadings, and in third case, a construction can collapse without visible reasons. The conducted successive static, dynamic and seismic analysis, executed due to the normative documents and the norms of supplier operating on the territory of the Russian Federation, in attachment to the real sections of bearings structural elements, allowed us expose the stated below percentage of the use of the examined elements of constructions. Lower belt of farms of coverage: on the norms of the Russian Federation, on the first maximum state percent of the use – 395 %; there is a percent of the use on the second maximum state – 999 %; on the norms of the Russian Federation taking into account loadings of supplier, on the first maximum state percent of the use – 339,3 %; there is a percent of the use on the second maximum state – 999 %. Overhead belt of farms of coverage: on the norms of the Russian Federation, on the first maximum state percent of the use – 495,2%; there is a percent of the use on the second maximum state – 361,4 %; on the norms of the Russian Federation taking into account loadings of supplier, on the first maximum state percent of the use – 150,8 %; there is a percent of the use on the second maximum state – 146,2%. Analysis presented allows establishing that at the load of overhead and lower belts of farms of coverage of hothouses, by combinations of loadings characteristic for the place of location of hothouse of type of 6d, their bearing strength, and buildings in general can not be provided
The aim of this work is to carry out numerical analysis of time behavior of electroconvection in membrane systems, such as a desalting channel of electrodialysis apparatus. The current-voltage curve and the solution flaw were analyzed theoretically using mathematical models of ions transfer taking into account electroconvection in smooth desalting channel consisting of ideally selective anion- and cation-exchange membranes. The Hurst numbers for different parts of the current-voltage curve were calculated in order to determine whether the parts were persistent. The Fourier-analysis of the oscillating term of the current-voltage curve was carried out for the first time so as to determine predominant frequencies in the signal. Frequencies of passing of complexes of vortexes through the cross-section of the desalting channel were calculated. Frequencies of oscillations of concentration profiles were determined. It was found that the frequencies of oscillations of the concentration profiles coincide with the frequencies of passing of complexes of vortexes through the cross-section of the desalting channel. The oscillations of the current-voltage curve were physically interpreted. Namely, it was shown that the main frequency of oscillations of the current-voltage curve corresponds to the frequency of oscillations of the concentration profiles. The oscillations of the concentration profiles, produced by the passing of complexes of vortexes, cause oscillations of conductivity and, consequently, cause oscillations of resistance and of the current density. It was shown that the main frequency of the signal corresponds to the frequency of passing of complexes of vortexes through the cross-section of the desalting channel