Experimental Studies of the Physical and Mechanical Properties of Glued Building Materials Based on Modified Veneer

2021 ◽  
Vol 410 ◽  
pp. 817-822
Author(s):  
Ruslan R. Khasanshin ◽  
Ruslan R. Safin ◽  
Shamil R. Mukhametzyanov
Keyword(s):  
Building Materials ◽  
Structural Characteristics ◽  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
Adhesive Interaction ◽  
Entire Volume ◽  
Timber Products ◽  
Ultraviolet Treatment ◽  
Birch Veneer

Today, glued timber products occupy a significant place in the volume of finished products of modern construction and woodworking enterprises. Plywood is one such product. The durability and structural characteristics of plywood depend on the quality of binder, the type of wood and the quality of veneer. The paper explores the technology of ultraviolet treatment of thermally modified birch veneer with subsequent production of waterproof plywood. The results of a study on the influence of the operating parameters of veneer modification on the complex of sorption and strength characteristics of plywood materials are presented. It is established that the combination of thermal modification of wood throughout the entire volume with surface treatment with ultraviolet radiation allows creating glued wood material with increased water resistance and high-quality adhesive interaction.

scholarly journals ENGINEERING MANAGEMENT OF MACHINE FOR FORMATION OF ARTIFICIAL SHELL ON SEED VEGETABLE CULTURES

2020 ◽  
Vol 61 (2) ◽  
pp. 165-174 ◽  
Author(s):  
I.L. Rogovskii ◽  
L.L. Titova ◽  
V.I. Trokhaniak ◽  
L.I. Marinina ◽  
O.T. Lavrinenko ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
Experimental Tests ◽  
Dynamic Mode ◽  
Seed Coating ◽  
Experimental Sample ◽  
Sowing Time ◽  
Seed Material ◽  
Internal Friction Coefficient

The article analyses the universalization of the seed material by its physical and mechanical properties by means of pre-sowing treatment, resulting in the formation of an artificial shell. As a result of the generalization, a technological scheme of obtaining an encapsulated seed and a design of a seed coating machine was proposed. A simulation model of the sowing accuracy process from the internal friction coefficient of seeds at different root mean square deviations of seed sizes is proposed. The regression equation for the influence of the dynamic mode of operation of the developed experimental sample of seed coating machine is established. According to the experimental studies’ results, the static and dynamic friction coefficients of the encapsulated vegetable seeds on the steel and plastic working surfaces of seed coating machine were established. Under the production conditions, experimental tests were conducted to compare the seedlings of untreated, coated, branded and encapsulated seeds of vegetables by the quality of prepared seed material and sowing time.

scholarly journals RESEARCH OF THE POSSIBILITY OF INCREASING THE QUALITY OF PREPARATION OF DRY MIXTURES IN A HORIZONTAL VANE MIXER

2021 ◽  
Vol 6 (10) ◽  
pp. 99-108
Author(s):  
S. Khanin ◽  
N. Kikin ◽  
O. Mordovskaya
Keyword(s):  
Compressive Strength ◽  
Building Materials ◽  
Experimental Studies ◽  
Ultimate Compressive Strength ◽  
Regression Equations ◽  
Technological Parameters ◽  
Sand Mixture ◽  
Paddle Mixer ◽  
Mixed Material

Paddle mixers with horizontal shafts are common at building materials enterprises for the preparation of concretes, mortars, dry mortars. A new design of a horizontal paddle mixer with rod elements located in front of the working surfaces of the blades, changing the trajectories of material particles, increasing their mobility, which leads to an increase in the degree of homogeneity of the mixed material, is considered. The aim of the study was to assess the influence of rod elements on the quality of preparation of a cement-sand mixture, to establish patterns of influence on it by the design and technological parameters of a two-shaft paddle mixer and to determine the areas of their rational values. The following tasks have been solved. A bench installation of a two-shaft horizontal paddle mixer with rod elements has been developed, on which experimental studies have been carried out on the preparation of dry cement-sand mixtures. For the criterion characterizing the quality of the mixture, the ultimate compressive strength of the prism specimens made from it is adopted. Regression equations are obtained that adequately describe the compressive strength of prism samples from the design and technological parameters of the mixer: the angle of the blades, the distance from the working surfaces of the blades to the rod elements, the rotational speed of the blade shafts, and their analysis is performed. The analysis of the change in the ultimate compressive strength of the prism specimens from the parameters under study is carried out, the rational ranges of their values are determined. It was found that a mixer with rod elements allows to obtain a dry cement-sand mixture, products from which have a higher compressive strength. During the work, the method of mathematical planning of experiments was used. As a result of the study, an assessment of the influence of rod elements on the quality of preparation of a cement-sand mixture was carried out, the regularities of the influence on it of the design and technological parameters of a two-shaft paddle mixer and the area of their rational values were established.

scholarly journals SUBSTANTIATION OF THE PARAMETERS OF TILLAGE RINK

2017 ◽  
Vol 2 (3) ◽  
pp. 24-28
Author(s):  
Иван Шаронов ◽  
Ivan Sharonov ◽  
Владимир Курдюмов ◽  
Vladimir Kurdyumov ◽  
Виктор Курушин ◽  
...  
Keyword(s):  
Moisture Content ◽  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
Soil Tillage ◽  
Content Structure ◽  
Technical Requirements ◽  
Winter Crops ◽  
Crops Yield ◽  
Specific Metal

The purpose of research is improving the quality of surface tillage during sowing of winter crops and, as a result, crops yield increasing. Quality compacting soil tillage rinks affect its physical and mechanical properties, such as moisture content, structure, and density, optimum value of which is regulated agronomic requirements for cultivation of specific agricultural crops. These properties affect the quality of seeding and water-air regime of the soil. Therefore, when conducting experimental studies, moisture content, structure, and soil density was controlled to optimize parameters and modes of operation of the rink to bring the above soil properties in compliance with agro-technical requirements. The quality of soil the proposed rink was assessed in comparison with existing rinks. The criterion of quality was the factor of conformity to the standard kcs, which characterizes the compliance of the density and structure of the soil reference values established by the agrotechnical requirements. The result of the research revealed that the maximum value of kcs = 0.84 is achieved at a speed ofv = 11 km/h and the ballast mass m = 78 kg. After tillage rinks seeder the factor of conformity to the standard kcs = 0.68; after soil tillage the existing rink kcs = 0.71; and after the processing of the proposed soil-cultivating rink the factor of conformity to the standard amounted to kcs = 0.84, which is significantly higher than after soil tillage of existing rink. While the specific metal content of the proposed ice rink will not exceed 116 kg per 1 m of width, which is 2.4 times less than that of the rink 3CCH-6 (283.6 kg/m).

scholarly journals SOME CHARACTERISTICS OF BUILDING MATERIALS OF ANCIENT KYYIVAN MONUMENTS OF THE X-TH - THE XIІ-TH CENTURIES

2020 ◽  
pp. 260-271
Author(s):  
Natalia Logvyn
Keyword(s):  
Water Absorption ◽  
Building Materials ◽  
Physical And Mechanical Properties ◽  
Raw Material ◽  
High Porosity ◽  
Light Yellow ◽  
Lime Kilns ◽  
Ancient Monuments ◽  
High Level

The development of brickwork technique in ancient Kyyiv dates back to the X- th century. Old Rus` monuments’ masonry was made of large thin bricks called “plynfa” and lime-and-ceramic mortar. The size of the X-th – the XII-th brick sides varies from 27 to 36 cm, its thickness – from 2.5 to 4.5 cm. Different kinds of clay and loess extracted from the territory of Kyyiv and its vicinities were used as a raw material for brick and ceramic addition to mortar. That is why bricks in Kyyivan monuments differ in colour from light yellow to orange and dark red. Some gruss or cut straw were used as addition to fat clay. Limestone was brought to Kyyiv from Chernihiv area and lime mortar was produced in lime kilns situated near building sites. Ceramic addition to mortar called “tsemianka” was of refined clay, and crushed brick waste was used as well. Bricks were burnt under the temperature of 1000 – 1200 degrees C. That’s why bricks were very firm regardless of chink-like pores appeared as a result of hand-moulding of brick. The author took some investigation for the purpose to determine physical and mechanical properties of ancient bricks of Kyyivan monuments. Bricks were picked out of excavations or waste after building repairs. Small cubes were cut out of bricks with the height equal to brick thickness. Those samples were examined concerning their strength by compressing them perpendicularly to the sides the bricks were bedded in mortar. The strength of samples varied from 100 to 200-300 kg per sq.cm, water absorption was 10 % to 20 %. Some bricks taken from the Cathedral of the Assumption of Kyyiv-Pechersk  monastery were the most firm. The strength of those samples was about 400-500 kg per sq. cm, their water absorption was the smallest, about 5.6 %. Because of high porosity and water absorption of building materials the surface of ancient masonry was exposed to destruction under the influence of temperature overfalls and precipitation, as it can be seen on the open parts  of walls of the Old Rus` monuments. To prevent destruction of masonry, the walls of ancient monuments were covered with fine lime-and-ceramic mortar. Fragments of original plaster can be found on the walls of the XI-th century monuments St.Sophia Cathedral and St.Michael Church of Vydubychy monastery in Kyyiv. High level of well-developed building technique and high quality of building materials caused durability of ancient masonry and constructions in Kyyivan monuments, which preserved until nowadays.

scholarly journals High quality of mortar with marble waste aggregate

2018 ◽  
Vol 18 (2) ◽  
pp. 387-399 ◽  
Author(s):  
Maria Teresa Gomes Barbosa ◽  
White José dos Santos ◽  
Claudia Valéria Gávio Coura
Keyword(s):  
Mechanical Properties ◽  
Construction Industry ◽  
Industrial Waste ◽  
Building Materials ◽  
Physical And Mechanical Properties ◽  
Urban Centers ◽  
Natural Sand ◽  
Alternative Materials ◽  
Marble Waste

Abstract The use of industrial waste has raised great interest regarding its potential of contributing both to the reduction of costs and to sustainable development. In this context, there has been an increasingly high number of studies addressing the use of alternative materials in the construction industry, especially when considering the difficulty in obtaining building materials near urban centers, which results in an increase in the final price due to transportation costs. This research has characterized and evaluated the use of crushed marble waste to replace natural sand in the production of mortar. Many admixtures of mortar were subject to research regarding their physical and mechanical properties. It has been concluded that mortars produced with sand made of crushed marble waste have improved mechanical properties when compared to traditional mortar.

scholarly journals STUDY OF ENERGY-SAVING LIQUID THERMAL INSULATING COATINGS BASED ON LOCAL FINELY DISPERSED SYSTEMS

2021 ◽  
Vol 17 (37) ◽  
pp. 189-203
Author(s):  
Zhanar O. ZHUMADILOVA ◽  
Vladimir P. SELYAEV ◽  
Ruslan E. NURLYBAEV ◽  
Yelzhan S. ORYNBEKOV ◽  
Indira B. SANGULOVA
Keyword(s):  
Thermal Conductivity ◽  
Heat Flux ◽  
Building Materials ◽  
Structural Characteristics ◽  
Experimental Studies ◽  
Hollow Microspheres ◽  
Stationary Heat ◽  
Thermal Insulating ◽  
Polymer Binders ◽  
Topological Features

Introduction: In recent years, in building materials science, there has been a tendency for the active introduction of hollow microspheres of various types for modifying the properties of building materials. Hollow microspheres are most widely used in the production of liquid thermal insulating coatings, which reduce heat loss, protect structures from corrosion and overheating, prevent condensation formation, reduce operating costs and increase the time between repairs. Aim: Assessment of the influence of the structural characteristics of granular systems on the properties of thermal insulating materials. Methods: It is proposed to determine and evaluate the structural characteristics of filler powders by the method of small-angle X-ray scattering. The most important feature of this method is analyzing the internal structure of disordered systems - particles, pore space, interfaces between heterogeneities of heterogeneous substances. When assessing thermal conductivity and thermal resistance, the stationary heat flux method was used following GOST 30290–94. The essence of the method is to create a stationary heat flux passing through a flat sample of a certain thickness and directed perpendicular to the front (largest) faces of the sample, measuring the density of this heat flux, the temperature of the opposite front faces and the thickness of the sample. Results and Discussion: The paper discusses the results of experimental studies that make it possible to create liquid thermal insulation coatings (LTIC) based on polymer binders, fine mineral powders, and a complex of modifying additives. Experimental studies of the structure and properties of heat-insulating coatings based on filled polymer binders confirm their superiority over foreign analogs. Conclusions: It has been established that during the production of LTIC, their heat-shielding properties can be regulated by changing: pressure, the viscosity of the molecular weight of the gas; porosity of macrostructure and clusters; the thermal conductivity of the solid and gas phase of the system; the coefficient of accommodation; coordination number; primary particle size; fractal dimension characterizing the topological features of the structure of particles, aggregates, globules, clusters and their tendency to dissipate the energy of gas molecules.

The Performance of the Ceramsite Concrete Block and its Application Research

2015 ◽  
Vol 744-746 ◽  
pp. 1543-1546
Author(s):  
Le Le Yu ◽  
Jia Dai Chen ◽  
Yi Wen Wu
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Building Materials ◽  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Concrete Block ◽  
Application Research ◽  
Working Process ◽  
Concrete Building

Ceramsite concrete and ceramsite concrete block are characterized by lightweight, high strength and good thermal insulation properties, which are widely applied to construction. If amoderate amount of polystyrene particles is added during the working process of ceramsite concrete block in order to improve its physical properties, a kind of new ceramsite concrete building materials is produced. Based on the experimental studies, the article expounds the physical and mechanical properties in terms of density, water absorption and compressive strength, with the purpose of providing reliable evidence for the application and popularization of new ceramsite concrete block.

The system of indicators of the quality of the carbon-carbon composite materials and technologies of their production

2018 ◽  
pp. 127-132
Author(s):  
T. N. Antipova ◽  
D. S. Shiroyan
Keyword(s):  
Composite Material ◽  
Low Cost ◽  
Experimental Studies ◽  
Carbon Matrix ◽  
Carbon Composite ◽  
Optimal Number ◽  
Laboratory Equipment ◽  
Carbon Composite Material ◽  
Carbon Composite Materials

The system of indicators of quality of carbon-carbon composite material and technological operations of its production is proved in the work. As a result of the experimental studies, with respect to the existing laboratory equipment, the optimal number of cycles of saturation of the reinforcing frame with a carbon matrix is determined. It was found that to obtain a carbon-carbon composite material with a low cost and the required quality indicators, it is necessary to introduce additional parameters of the pitch melt at the impregnation stage.

scholarly journals Mortars with Recycled Aggregates from Building-Related Processes: A ‘Four-Step’ Methodological Proposal for a Review

2021 ◽  
Vol 13 (5) ◽  
pp. 2756
Author(s):  
Federica Vitale ◽  
Maurizio Nicolella
Keyword(s):  
Building Materials ◽  
Thermal Analyses ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Research Trends ◽  
Mix Design ◽  
Recycled Aggregates ◽  
Design Parameters ◽  
Natural Aggregates ◽  
By Products

Because the production of aggregates for mortar and concrete is no longer sustainable, many attempts have been made to replace natural aggregates (NA) with recycled aggregates (RA) sourced from factories, recycling centers, and human activities such as construction and demolition works (C&D). This article reviews papers concerning mortars with fine RA from C&D debris, and from the by-products of the manufacturing and recycling processes of building materials. A four-step methodology based on searching, screening, clustering, and summarizing was proposed. The clustering variables were the type of aggregate, mix design parameters, tested properties, patents, and availability on the market. The number and the type of the clustering variables of each paper were analysed and compared. The results showed that the mortars were mainly characterized through their physical and mechanical properties, whereas few durability and thermal analyses were carried out. Moreover, few fine RA were sourced from the production waste of construction materials. Finally, there were no patents or products available on the market. The outcomes presented in this paper underlined the research trends that are useful to improve the knowledge on the suitability of fine RA from building-related processes in mortars.

scholarly journals Being a Gambler during the COVID-19 Pandemic: A Study with Italian Patients and the Effects of Reduced Exposition

2021 ◽  
Vol 18 (2) ◽  
pp. 424
Author(s):  
Maria Anna Donati ◽  
Silvia Cabrini ◽  
Daniela Capitanucci ◽  
Caterina Primi ◽  
Roberta Smaniotto ◽  
...  
Keyword(s):  
Structural Characteristics ◽  
Gambling Behavior ◽  
Online Gambling ◽  
Problem Gamblers ◽  
Electronic Gambling Machines ◽  
Electronic Gambling ◽  
Gambling Market ◽  
The Impact ◽  
Gambling Activities

The COVID-19 pandemic, with the consequent lockdown of about 3 months, can be viewed as an experimental model to observe the impact of the depletion of environmental factors that stimulate gambling, particularly electronic gambling machines (EGMs) that were set to zero. The effects of some structural characteristics of gambling activities that increase gambling behavior were studied among disordered gamblers in treatment in this unique scenario. In fact, studies investigating the effects of the lockdown on problem gamblers (PGs) under treatment are missing. The aims of this study were to analyze patients’ gambling behavior and craving during the lockdown and to conduct a comparison between gambling disorder (GD) symptoms at the beginning of the treatment and during lockdown. The study was conducted in Italy, the European country with the largest gambling market and the first to be affected by the virus. Data were collected through a semi-structured telephone interview conducted by healthcare professionals. Participants were 135 PGs under treatment (109 males, mean age = 50.07). Results showed that most PGs achieved a significant improvement in their quality of life, with less gambling behavior, GD symptoms, and lower craving. No shift toward online gambling and very limited shift towards other potential addictive and excessive behaviors occurred. The longer the treatment, the more monitoring is present and the better the results in terms of symptoms reduction. Individual and environmental characteristics during the lockdown favored the reduction in symptoms. Consideration for prevention and treatment are discussed.

Sign in / Sign up

Export Citation Format

Share Document