Effect of thermooxidative degradation on the physicomechanical characteristics of polyamide cord yarn

Data on laboratory works on resistance of materials are provided, the assessment of errors of results of measurements and experiments is given, statistical processing of experimental data is in detail stated. The book contains information on nondestructive methods and control devices of characteristics and diagnostics of materials and designs. In a grant the International system of units (SI) (tab. 1 of the Appendix) is used, designations of sizes are accepted according to the international recommendations of ISO. Data on physicomechanical characteristics of steel, cast iron, non-ferrous metals, wood and polymers and the allowed tension for them are provided in tab. 2-8 of the Appendix. The grant is intended for the students studying courses of resistance of materials, mechanics of materials and designs, applied mechanics, construction mechanics and construction designs.

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Estimation of the oxygen-limiting amount consumed by polymeric melt in the thermooxidative degradation process

Journal of Applied Polymer Science ◽

10.1002/app.20182 ◽

2004 ◽

Vol 92 (5) ◽

pp. 2840-2844

Author(s):

G. V. Kozlov ◽

G. B. Shustov ◽

G. E. Zaikov

Keyword(s):

Degradation Process ◽

Thermooxidative Degradation

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The Influence of Molecular Weight on the Orientation and Properties of Polymethyl Methacrylate Sheets

International Polymer Science and Technology ◽

10.1177/0307174x1804500204 ◽

2018 ◽

Vol 45 (2) ◽

pp. 47-51

Author(s):

I.D. Simonov-Emel'yanov ◽

K.V. Shirshin ◽

P.V. Motsinov ◽

S.V. Vlasov

Keyword(s):

Molecular Weight ◽

Elastic Modulus ◽

Polymethyl Methacrylate ◽

Considerable Increase ◽

Deformation Characteristics ◽

Physicomechanical Characteristics

The influence of molecular weight on the process of orientation stretching and the combination of physicomechanical characteristics of specimens of polymethyl methacrylate (PMMA) is examined. Orientation stretching and increase in the molecular weight of PMMA from 0.52 to 4.6 × 106 g/mol lead to a considerable increase in strength and elastic modulus (σt by a factor of 2.6, E by a factor of 2.5). It is established that the deformation characteristics of oriented PMMA specimens increase by a factor of 10 when the molecular weight is increased from 0.52 to 4.6 × 106 g/mol, which opens up new possibilities in the processing of sheets and films of PMMA.

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IMPROVING THE EFFICIENCY OF FIBRE CONCRETE PRODUCTION

Construction Materials and Products ◽

10.34031/2618-7183-2019-2-2-4-9 ◽

2020 ◽

pp. 4-9

Author(s):

V. Nelyubova ◽

V. Babaev ◽

Nataliya Alfimova ◽

S. Usikov ◽

O. Masanin

Keyword(s):

Building Materials ◽

Production Efficiency ◽

Raw Materials ◽

Basalt Fiber ◽

Operational Reliability ◽

Fiber Reinforced Concrete ◽

Technological Parameters ◽

Optimal Method ◽

Physicomechanical Characteristics ◽

Concrete Production

fiber concrete is one of the types of effective building materials that ensure the operational reliability of structures due to a set of unique properties. However, the maximum physicomechanical characteristics of this type of products are achieved only if the fiber is evenly distributed in the concrete matrix and the optimum ratio of raw materials is reached. In this connection, the aim of the work was to increase the production efficiency of fiber-reinforced concrete by optimizing the formulation and technological parameters of its manufacture. The optimal method of introducing the fiber into the concrete mix and the type of superplasticizer were previously determined, which allowed ensuring the maximum physicomechanical characteristics of the products. Optimization of prescription parameters was carried out using the method of mathematical planning of the experiment, where the amount of cement, superplasticizer and basalt fiber were varied. After processing the results, the dependences of the compressive strength on variable factors were obtained, which would allow to select the optimal dosages of raw materials for given mechanical characteristics of the products.

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EFFICIENCY OF REINFORCEMENT OF TECHNOLOGICAL SOIL BY MINERAL MODIFIERS

Bulletin of Belgorod State Technological University named after V G Shukhov ◽

10.34031/article_5d14bdcc8eca43.21244159 ◽

2019 ◽

Vol 4 (7) ◽

pp. 14-23

Author(s):

Т. Дмитриева ◽

T. Dmitrieva ◽

Н. Куцына ◽

N. Kucyna ◽

А. Безродных ◽

...

Keyword(s):

Raw Materials ◽

Road Construction ◽

Soil Reinforcement ◽

Production Costs ◽

Concrete Mixture ◽

The Road ◽

Physicomechanical Characteristics ◽

Advantages And Disadvantages ◽

Complex Binder ◽

Technogenic Raw Materials

The paper discusses the main aspects of soil reinforcement in road construction by adding a binder component to them. The use of this technology allows to solve the problem of high-quality raw materials shortage while improving the physicomechanical characteristics or keeping them at the same level, as well as to increase labor productivity and reduce production costs. The technogenic raw materials for the production of soil concrete were studied, the main physicomechanical characteristics and requirements that must be taken into account when selecting the composition of the soil concrete mixture were analyzed. The paper compares the physicomechanical characteristics of the road composite, reveals the advantages and disadvantages of introducing binder components of various types: cement, cement with modifier and a complex binder. It has been established that the introduction of a complex binder or cement with modifier contributes to the improvement of the physicomechanical characteristics while reducing the consumption of cement in the composition of the soil-concrete mixture compared to traditional soil-concrete with cement.

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