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Theoretical studies of dynamic soil compaction by wheeled forestry machines

Diagnostyka 2020年第4期21卷 3-13页

作者： GRIGOREV, Igor KUNICKAYA, Ol'ga BURGONUTDINOV, Albert IVANOV, Viktor SHUVALOVA, Svetlana SHVETSOVA, Viktoria STEPANISHCHEVA, Marina TIKHONOV, Evgeniy Department of Technology and Equipment of Forest Complex Yakut State Agricultural Academy Yakutsk Russia Department of Roads and Bridges Building Perm National Research Polytechnic University Perm Russia Bratsk State University Bratsk Russia Department of Descriptive Geometry and Engineering Graphics Saint Petersburg State University of Architecture and Civil Engineering Saint-Petersburg Russia Department of Reproduction and Processing of Forest Resources Bratsk State University Bratsk Russia Department of Transport and Technological Machinery and Equipment Federal State Budget Educational Institution of Higher Education "Petrozavodsk State University" Petrozavodsk Russia

The impact of forest skidding machine tires on the soil differs depending on topography, soil properties, and type of the wheel system. The development of a mathematical model describing the entire dynamic process is a challenging but relevant task to assess the level of impact. The work aims mathematical modeling of the impact caused by the skidding system on the forest soil employing Kelvin-Voigt theory with additional elastic element and Laplace transform equations. A dynamic model represents the "tractor-timber bundle-soil" system. According to the results of mathematical modeling, it was found that studying the vertical vibrations and vibrations of sprung mass in longitudinal and transverse planes is sufficient for examining dynamic soil compaction. Developed methods of statistical dynamics with the presentation of the track surface microroughness and the theory of linear elastic and viscous soil deformation showed that each pass of the skidding system is ac-companied by additional dynamic soil compaction. Its maximum value depends on the properties of the soil and skidding system, as well as on the presence of resonant zones in the frequency spectrum. The results of these studies provide an opportunity to predict the exposure level of skidders and establish new solutions to minimize negative consequences for the environment and productivity of the forest industry. © 2020 Polish Society of Technical Diagnostics. All rights reserved.

关键词： Laplace transforms

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On the Wear Intensity Ratio of a Striker under Dynamic and Static Conditions

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IOP Conference Series: Earth and Environmental Science 2020年第6期459卷

作者： V Bolobov S Chupin Le Thanh Binh Department of Mechanical Engineering Saint Petersburg Mining University Saint Petersburg Russia Department of Descriptive Geometry and Engineering Graphics Saint Petersburg Mining University Saint Petersburg Russia

The results of experiments on determination of the cylindrical part mass loss of the cone-shaped strikers made of 38XM (AISI P20), У8 (AISI W1-A), and X12MФA (AISI D2) steels, which have been subjected to heat treatment applied by the striking tools manufacturers, and additional cold treatment, with their friction and abrasive wear on granite, are presented. It was found that the strikers made of steel X12MФA with all types of heat treatment show the greatest wear resistance under the wear conditions (static conditions), while the strikers made of 38XM have the lowest wear resistance. Cryogenic treatment and, to a lesser extent, cold treatment increase the wear resistance of all materials. The comparison of set values of wear resistance Ist and hardness HV of the strikers, as well as the analysis of their microstructure allows to conclude that wear resistance of a tool depends not only on its hardness, but also on the type, volume, shape of carbides forming the structure of material used for tool manufacturing. For this reason, after the cryogenic treatment, the tool made of X12MФA steel shows the greatest wear resistance, because its material has the highest content of carbon (~1.5%) and alloying elements (~13%), which provides up to 10.8% increase in the number of fine carbide particles in its structure, that ensure wear resistance increase, after the cold treatment. The results obtained for Ist are compared with the earlier obtained data on wear resistance of the same striker at striking upon granite (in dynamic conditions). The conclusion about similarity of the wear mechanisms of the analyzed strikers in dynamic and static conditions is made.

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Efficiency improvement of forest machinery exploitation

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Diagnostyka 2020年第2期21卷 95-109页

作者： Grigorev, Igor Kunickaya, Ol'ga Prosuzhih, Alexey Kruchinin, Igor Shakirzyanov, Dmitry Shvetsova, Viktoria Markov, Oleg Egipko, Sergey Department of Technology and Equipment of Forest Complex Yakut State Agricultural Academy Yakutsk Russia Department of Logging Technology and Machines Ukhta State Technical University Ukhta Russia Department of Transport and Road Construction Ural State Forestry University Ekaterinburg Russia Department of Engineering of Technological Machines and Equipment Ukhta State Technical University Ukhta Russia Department of Descriptive Geometry and Engineering Graphics Saint-Petersburg State University Architecture and Civil Engineering Saint-Petersburg Russia Department of General Technical Subjects Federal State Budget Educational Institution of Higher Education petrozavodsk State University Petrozavodsk Russia Department Machines Environmental Engineering Don State Agrarian University Novocherkassk Russia

The purpose of this work was to develop a model of the interaction process between the wheeled forwarder and the soil of the cutting area, which allows evaluating the influence of soil conditions, the parameters of the wheeled forwarder, as well as load and number of cycles of its application, on the indicators of resistance and adhesion of the forwarder to the traction surface. Modeling results for 3-and 4-Axle forest machines with different load levels showed that for different soil categories, types of bodies, and tire sizes. The results of the approximation analysis enabled the derive of calculation formulas for estimating the propulsive coefficient and rut depth after the first passage depending on the values of load-bearing capacity, body load coefficient, wheel width, and soil deformation module. The proposed model can be used at laying down the skidding roads and its optimization not only in economic terms but also with respect to the environment as intensive harvesting operations lead to extensive soil destructions. The practical application of the results is expressed in increased performance capacities of wood skidding operations and minimization of costs for restoring the productivity of forest area. © 2020 Polish Society of Technical Diagnostics. All rights reserved.

关键词： Soils

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Engineering method for assessing the strength of reinforced concrete beams

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IOP Conference Series: Materials Science and Engineering 2019年第2期537卷

作者： O V Snezhkina Department of Descriptive geometry and graphics of Penza State University of Architecture and Construction Penza Russia

A calculation method is proposed that combines two existing methods for calculating the strength of reinforced concrete beams. The author of the article considers the possibility of presenting the work of a reinforced concrete beam in the form of an arch with a curvilinear shape with a puff, which is a statically definable system. The operation of a reinforced concrete beam with a relative span of a slice from 1 to 3 is modeled as an arched system with a horizontal stretched reinforcing belt and a compressed concrete strip of curvilinear shape. The purpose of the tightening in a beam with an average relative cut span is to cancel the bending moment inherent in a simple beam. Thus, this model (arch with tightening) most fully reflects the work of reinforced concrete beams with an average relative cut span compared to the model adopted in regulatory documents.

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Geometric modelling of building forms using BIM, VR, AR-technology

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IOP Conference Series: Materials Science and Engineering 2019年第4期687卷

作者： Z O Tretyakova M V Voronina V A Merkulova Department of Descriptive Geometry and Graphics Saint-Petersburg Mining University 2 21st Line Saint Petersburg 199106 Russia

Modern conditions set new tasks for designers and impose previously not arisen requirements. Along with the design, an important factor is the further presentation of the construction project to the potential consumer. The use of modern VR and AR technologies allows us to bring several advantages to the design that complements the living, real world with digital models. Therefore, there was a need to change the methods of teaching the design for students of construction, considering these factors. Purpose of research - to create a complete information model of the building with the help of computer-aided design, as well as the research of the impact of augmented reality technologies on the design conditions and presentation of the project. Method of research: observation, comparison, and analysis of the results of research of information and computer technologies, observation, comparison and using the experience of the university. The article presents the positive results of creating an information model of the building with the help of graphic programs. Traditional and progressive methods of design, new opportunities of VR and AR-technologies are considered.

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Socio-Cultural Problems of Sustainable Urban Environment

Socio-Cultural Problems of Sustainable Urban Environment

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International Multi-Conference on Industrial Engineering and Modern Technologies 2018

作者： Shabatura, L. Bauer, N. Iatsevich, O. Institute of Service and Industry Management Department of Humanities and Technologies Tyumen Industrial University Volodarskogo 38 Tyumen625000 Russia Construction Institute Department of Descriptive Geometry and Graphics Tyumen Industrial University Volodarskogo 38 Tyumen625000 Russia Institute of Service and Industry Management Department of Foreign Languages Tyumen Industrial University Volodarskogo 38 Tyumen625000 Russia

Urban environment is a complex concept that includes material structure (buildings, constructions, transport, industry, utility lines, etc.) and natural environment with a variety of anthropogenic factors. Consistent patterns and directions of development of the urban environment are interrelated with philosophy, religion, science, aesthetics, socio-economic relations, natural and climatic characteristics and culture of a particular country. According to the methodological principles of anthropologism and historism, the authors understand the urban environment as a continuum of coexistence, communication, interactions, relationships and needs of different nature and level, as a socio-cultural space of human life. Leading research workers from different scientifical branches present the urban space in contemporary anthropological versions of ontological theories as a unique space of human existence. Being a symbol of culture, the city, as the mechanism of its conversion to real forms of life, developing a socio-psychological community and the human's personality. Urban environment designers try to form the ambience under the influence of processes taking place in society at each historical stage. At the same time, the urban environment has an impact on the social well-being, worldview, attitudes, behavior and culture of the citizens. Therefore, the urban environment must meet the functional, aesthetic, spiritual, cultural human's needs, promoting to the creation of favorable conditions for his life. © Published under licence by IOP Publishing Ltd.

关键词： Urban transportation

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Probabilistic Assessment of the Durability of Reinforced Concrete Piles under Chloride Aggression

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IOP Conference Series: Materials Science and Engineering 2020年第2期753卷

作者： I I Ovchinnikov O V Snezhkina I G Ovchinnikov Tyumen Industrial University Tyumen Volodarsky Street 38 625000 Russia Department of descriptive geometry and graphics Penza State University of Architecture and Construction Penza Herman Titov Street 28 440028 Russia Perm National Research Polytechnic University Perm Komsomolsky prospect 29 614990 Russia

The article presents a model of the deformation of a reinforced concrete pile, which is subjected to the joint action of the load and chloride corrosion. The model takes into account the probabilistic nature of corrosion processes, the variation of the geometric and strength characteristics of the pile, the probabilistic nature of the load. A method for calculating the strength and durability of the pile, which takes into account the stages of the process of interaction of the pile with chlorides, is given, a calculation analysis is performed. The influence of various parameters on the durability of reinforced concrete piles is analyzed. A correlation dependence of pile durability on compressive load and a durability histogram are constructed. It has been established that the lifetime of a pile with a 95% security is 16 years, with a security of 70% - 52 years, with a security of 50% - 80 years.

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Directions For Improving the Efficiency of Forest Clear Cutting on the Territories of Reservoirs and Waterworks Under Construction

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IOP Conference Series: Earth and Environmental Science 2020年第1期574卷

作者： V Kalyashov A Iliin S Shuvalova O Leonova V Shvetsova Department of descriptive geometry and engineering graphics Saint Petersburg state University of architecture and civil engineering 4 2nd Krasnoarmeiskaya Street Saint Petersburg 190005 Russian Federation Department of water energy and ecological feasibility JSC Lenhydroproject Ispitateley prospect 22 Saint Petersburg 197227 Russian Federation

The article deals with the issues of increasing the forest resources use extent on the forested areas of reservoirs' flooded territories of hydroelectric power stations (HPPs) – both projected and under construction- in multi-forest areas of the Russian Federation. The necessity of forest clear cutting and forest clearing carrying out on flooded territories and the importance of these measures for ensuring favorable environmental conditions in the area of hydro construction and in the water area of reservoirs are substantiated. The estimation of the wood volume cut in the process of reservoirs creation is presented and the reasons for leaving wood to be flooded are considered. The factors and circumstances that affect the indicators of economic efficiency of forest clear cutting are described. A comparative assessment of the applied technologies of forest clear cutting is made, ways to increase its profitability are outlined, and the impact of profitability on decision making on leaving wood to be flooded in the process of reservoirs' territory preparation is estimated.

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Problems of technological processes selection in logging

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IOP Conference Series: Materials Science and Engineering 2020年第1期817卷

作者： V Kalyashov A Smirnova N Tjurin L Gromskaya T Antonova Descriptive Geometry and Engineering Graphics Department Saint Petersburg State University of Architecture and Civil Engineering 4 2-nd Krasnoarmeyskaya Street Saint Petersburg 190005 Russian Federation Department of forest policy Economics and management St. Petersburg State Forest Technical University 5 Institutskiy Lane St. Petersburg 194021 Russian Federation Department of Industrial Transport St. Petersburg State Forest Technical University 5 Institutskiy Lane St. Petersburg 194021 Russian Federation

The article deals with current issues of the logging enterprises effective functioning with assortment technology for wood harvesting in the Leningrad region of the North-West Federal District of Russia. A survey of the production activity of a number of enterprises that use logging technology based on harvesters and forwarders was carried out. The results of technical and economic assessment of this technology usage are presented, the reasons of the decrease in the efficiency of the technological process of the logging are identified, the alternative assortment technologies are considered, and recommendations on selection of technological processes and systems of logging machines are made.

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Designing mountain drawings with the help of computer-aided design (CAD)

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IOP Conference Series: Materials Science and Engineering 2018年第1期451卷

作者： V A Merkulova M V Voronina Z O Tretyakova Department of Descriptive Geometry and Graphics Saint-Petersburg Mining University 2 21st Line Saint Petersburg 199106 Russia

The relevance of the researched issue is caused by the problems due to the difficulties of the representation of geometric objects in the space. When deciding the tasks of descriptive geometry and Engineering graphics, students find it difficult to imagine a general view of the subject in the space from their images on the main projection plane. The aim of the article is to form concepts for the basics of graphics and justifying the use of spatial modeling techniques to generate geometric models and designed objects in the minds of students with the help of a computer-aided design program by the example of the Russian company ASCON KOMPAS. The leading methods of research of this problem are the information and computer technology, observation, comparison, analysis and monitoring of the above problems, using the experience of working at the university. Results of the study. In the article the positive results of application of the graphic program KOMPAS by the example of construction of an axonometric drawing of mine are presented. Practical significance. The research is aimed at solving problems on descriptive geometry and Engineering graphics, using three-dimensional modeling; the formation of concepts graphic bases of thinking and solving engineering problems of any level.

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