bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human resources for BIM jobs in the AEC industry in Vietnam: an investigation on job positions and requirements
Authors: Nguyen The-Quan , Dau-Thi Nguyet-Anh , Dao Thuy-Ninh 
Published: October 2020

Abstract
The paper presents research results from 90 BIM jobs vacancies for the AEC industry in Vietnam which were advertised on popular recruitment channels. The results show that BIM jobs in the South are more popular than in the North and the Central. BIM-related job positions are different from company to company, but this study groups those positions into three basic positions according to the international best practice approach: BIM Manager, BIM Coordinator, BIM Modeler. For BIM Modelers, their main job is to develop 3D models, deploy design documents, and coordinate with stakeholders to perform the work. BIM Coordinator’s on-demand job is to coordinate models across disciplines, check conflict and report, control models, support project management. The main task of a BIM Manager is to manage and develop BIM uses, to ensure the information to be communicated among the parties in the projects, and train BIM human resources in the company. There are many requirements for these positions, among them are the two basic requirements of “experience” and “software” (organisations may use different software for the BIM uses they apply). The article also emphasizes the need to have more involvement of professional associations, state management agencies, etc. to standardize job positions, then later they can award BIM licenses to the proper human resources appropriately.
Theoretical aspects of using fragments of destroyed buildings and structures of Iraq
Authors: Ahmed Ahmed Ahmed Anees 
Published: October 2020

Abstract
The relevance of the work is determined with the search for alternative sources of raw materials for the construction industry, associated with the utilization of technogenic waste. The novelty of the paper is to identify the scientific regularities of the influence of concrete scrap from fragments of destroyed buildings and structures on the formation of the micro-structure of light and heavy concrete. Concrete scrap was prepared as both fillers of cement materials and small aggregates, based on which concretes with high mechanical properties were created. The compositions were designed from the point of view of geonics (geodaetica), in particular, taking into account the law of affinity of structures. The strength characteristics of concrete mixes were studied in accordance with EN 12390-3. In addition, microstructural, morphological and thermal properties of raw materials and concretes were determined during 28-day of curing. For the first time, a dense microstructure of the composite was provided, both by products of Portland cement and hydration, and, in part, by products of hydration of previously unreacted clinker, whose minerals are present in concrete waste and are activated when they are crushed. The use of fragments of destroyed buildings and structures as a filler of cementing material when replacing Portland cement up to 20% allows getting better compressive strength, both heavy and light concretes.
Plane model of particle separation in disintegrators with internal circulation of the grinding material
Authors: Orekhova T N , Kachaev A E , Prokopenko V S 
Published: October 2020

Abstract
The paper offers a method for evaluating the separation process of fine particles in the design of a classifier of a disintegrator with internal circulation of the dispersed material. Disintegrator type mills are fairly common in the construction materials industry and related industries. However, there are a number of technological problems with this type of equipment, which hinder their wider use in the production of dispersed powders with a high specific surface area. One of these problems is the presence of under-ground (coarse) particles in the volume of the finished product of a given fraction. The quality of classification is evaluated taking into account the velocity parameters of fine particles in the classifier device built into the disintegrator body. A new design of a gravity-type classifying device is considered, which contributes to the efficient return of large substandard particles to the finishes grinding in the disintegrator grinding chamber. The publication provides a method for determining the speed parameters of particle dynamics in the chamber of the classifier device of a disintegrator mill, and also presents a model for numerical calculation of the efficiency of the classifier device. This theoretical method of assessing the quality of separation of particles in the disintegrator is to define a measure of the degree of separation, to assess the effectiveness of recycle coarse fractions of grinding material powder: degree of operational separation shows the ability of disintegrator to operate in various process modes, and sets the granulometric boundaries for obtaining a particular fraction after grinding in the disintegrator.
Energy characteristics of sands of deposits in the Ivanovo region
Authors: Morozova M V , Akulova M V , Frolova M A 
Published: October 2020

Abstract
It is proposed to use the energy potential of rock-forming minerals obtained in the process of rock synthesis as an energy criterion for ranking raw materials for the production of construction materials. The energy of atomization and its specific values calculated based on the principles of crystal energy are used as a quantitative parameter. The estimation of two deposits of sands of the Ivanovo region on energy of atomization, specific mass energy of atomization, specific volume of energy of atomization (energy density) is carried out. It was found that, despite the difference in the chemical, mineral composition and origin of rocks, macroenergy parameters have similar values. The energy density value allows classifying the considered sands as high-energy-dense. The possible level of use of this energy reserve due to mechanical crushing of raw material is established. Quantifying potential energy of the system that fallen after crushing the material in the surface was carried out based on the values of critical surface tension and specific surface area of raw materials (formed after the process of mechanical grinding). The level of possible use of the potential energy reserve due to the formation of a new material surface was characterized by the activity of the surface of fine samples. The obtained values of surface tension and surface activity showed that the sands of the Nekhtskoe deposit, in comparison with the sands of the Khromtsovskoye deposit, are preferable to be used as an active fine-dispersed component for obtaining binding compositions.
The advantages of using polymer-bituminous concentrate for the production of polymer-bituminous binders
Authors: Denisov V P , Akimov A E , Yadykina V V 
Published: October 2020

Abstract
Construction of road surfaces with an extended service life, as well as the transition to methods of volumetric and functional design of asphalt concrete mixtures, leads to the need for the use of polymer-bituminous binders, as bitumen without polymer modifiers does not provide the required physical and mechanical characteristics and durability. Traditional PBB production technologies involve the use of complex technological processes and equipment. In addition, existing technological features lead to a significant decrease in the quality of the resulting polymer-bituminous binder. In this paper, we consider the possibility of obtaining PBB with high physical and mechanical parameters by using the PBC modifier (polymer-bituminous concentrate). The modifier under study is a polymer dispersed in an oil base and stabilized with active components. When added to bitumen, a colloid mill and complex processes of preparation and maturation of the binder are not required. Experiments have shown that the resulting binder has the characteristics of PBB, in particular, an extended temperature range of plasticity, elasticity and resistance to cyclic loads. At the same time, gentle heating modes provide increased resistance to aging during the preparation of asphalt concrete mixture and its operation. The ease of use of this modifier makes it possible to obtain PBB with a wide range of characteristics that correspond to the operating conditions.
The acceleration of the peat secondary consolidation due to the sorption of bound water with disperse clay
Authors: Ivakhnova G Yu , Nevzorov A L 
Published: October 2020

Abstract
According to observations at the experimental site, the primary consolidation of the 6-6.5 m peat layer completed in 3-5 years after the sandy embankment was filled on. Secondary consolidation of peat caused by the removal of bound water from micropores and channels within vegetation remains is the cause of settlement that has not stabilized for decades. The aim of laboratory research was to evaluate the effects of two methods for peat settlement stabilization at the stage of secondary consolidation – vacuuming and sorption of bound water of disperse clay. Tests were carried out with peat, which has a degree of decomposition of 40-45 %, a density of 0.98–1.12 g/cm3, a void ratio of 11.8–13.8. Samples with a diameter of 87 mm and a height of 30, 50 and 70 mm were set into odometers and maintained under a load of 25, 50 and 100 kPa for 5-6 months, after that experiments to stabilize secondary consolidation were started. In contrast to vacuuming, the use of pre-dried clay with the following properties turned out to be very effective: maximum hygroscopic water content 43%, liquid limit 198%, plastic limit 58%, specific surface area 411 m2/g. The volume of clay was about 20% of the volume of peat samples. Deformations of samples due to water sorption by clay increased within 2-4 days and reached 0.09-0.11 of their initial height. The penetration of clay into the peat can be performed by drilling of boreholes, vibration stamping and other methods.
The research of different types of clays of the Kazakhstan for the production of wall ceramic products
Authors: Sarsenbayev B K , Karshyga G O , Budikova A M , Shakey A M 
Published: October 2020

Abstract
The manuscript presents the results of analysis and synthesis of researches of scientists of the CIS and Kazakhstan on the use of various clays for the production of wall ceramic products. There was investigated the application of refractory and brown clays, loam to optimize the composition of the furnace charge and the choice of technological parameters of the production of wall ceramic products. The drying and burning properties of the samples burned at 850 °C, 900 °C, 950 °C, 1000 °C and 1050°C, 1100÷1150 °C with determination of strength, shrinkage, water absorption of the material at all specified burning temperatures were studied. The optimal burning temperatures for the study of the burning properties of the above three clays are determined. In many regions of the Republic of Kazakhstan the problem of production of high-quality wall ceramic manufacture is particularly acute. Most seasonal plants turns out low-branded products (the M75-100, B < 25), often not conforming to requirements of normative documents, does not have the expanded range, the decorative brick necessary for construction of low houses (country, cottage buildings) as implementation of the similar program requires, first of all, detailed studying of technological and physical and chemical features of clay raw materials is not issued.
Binders from gypsum-containing waste and products based on them
Authors: Alfimova N I , Pirieva S Yu , Elistratkin M Yu , Nikulin I S , Titenko A A 
Published: October 2020

Abstract
Gypsum binders are among the most environmentally friendly from the point of view of their production. The raw material base for their production is represented not only by natural raw materials, but also by a wide variety of technogenic materials, phosphogypsum is the most multi-ton and studied of them. At the same time, citrogypsum is also a promising raw material for the production of gypsum binders and, in comparison with phosphogypsum, does not contain toxic impurities that require the development of additional measures for their removal. Synthesis of the binder from gypsum-containing waste is possible with the use of various technologies using autoclaves, chemical reagents and at elevated temperature and atmospheric pressure. Each method has its own advantages and disadvantages. The most acceptable from the point of view of industrial production is the method of calcination at atmospheric pressure, but it does not allow producing high-strength binders and products based on them. It is possible to increase the efficiency of using such binders for the production of small-piece products by applying special molding modes with increased pressing pressure. The possibility of obtaining a binder from the waste of citric acid – citrogypsum production by calcination in a semi-industrial plant is shown. Using standard methods, a complete analysis of the resulting binder was performed: granulometry, grain shape and morphology, normal density and setting time. A comparison was made with construction gypsum (G5) and high-strength gypsum (G16). The possibility of obtaining small – piece products from a synthesized binder with a dry compressive strength of 20 MPa is shown by using the semi-dry pressing method at high pressures.
The use of augmented reality technology in the reconstruction of a lost cultural heritage site
Authors: Tomilina E M , Gontar E V , Frolova M A 
Published: October 2020

Abstract
The paper is devoted to the study of the possibility of using augmented reality technology in the process of hypothetical (virtual) restoration of the authentic appearance of lost cultural heritage structures on the example of an object of regional significance - the cinema “Sever”. Based on the collected archival data and field studies, a historical and retrospective analysis of the cultural heritage object and its territory is presented, the construction history of the monument site is developed, dimensional drawings are restored and three-dimensional models of the object in various historical periods of the monument life are created. A detailed description of actions for creating an augmented reality object and exporting its animated model to an accessible digital platform (Instagram) was developed. The expediency of using the augmented reality approach in the reconstruction of lost cultural heritage objects is shown. This technology allows recreating the appearance of the lost monument in conjunction with the actual architectural component of the urban space. Successful implementation of this approach will allow for more detailed cultural, historical, archaeological, ethnographic, anthropological and other research.
Employment of vacation queueing models for maintenance of engineering systems of residential buildings
Authors: Afanasyev G A 
Published: October 2020

Abstract
We consider two main functions for servicing the housing stock-scheduled prophylactic inspection and repair of technical objects and the elimination of sudden malfunctions of technical equipment. An approach to analysis based on vacation queueing systems is proposed. We introduce two vacation queueing models in which during vacations the team relizes the prophylactic inspection and repair of technical objects. In the first model during vacation the elimination of sudden malfunctions of technical equipment stops and the second model has a working vacation scheme. For each model the characteristics which determine the quality of the work of the server (team), as well as the boundaries of the change of parameters at which the team copes with the work from the standpoint of a particular criterion are defined.
Influence of design and technological parameters of a high-speed paddle mixer on the quality of dry building mixes
Authors: Brazhnik Yu V , Nesmeyanov N P , Brazhnik A A 
Published: October 2020

Abstract
Today, one of the most promising building materials is dry building mixes. Their production is not only a large segment of the construction market, but also a kind of testing ground for promising developments of modern technological equipment. The paper discusses the design of a high-speed fixed drum paddle mixer for producing modified dry building mixes with a complex recipe. The question is raised about the complexity of the uniform distribution of components in the total volume of the mix. A number of existing factors affecting the distribution of components of the prepared mix are determined. Criteria for evaluating the quality of the finished mix are given. The method for determining the influence of design and technological parameters on the quality indicators of the finished product is described. The method of experimental research that allows evaluating the influence of the design and technological parameters of the mixer on the inhomogeneity coefficient of the resulting dry construction mix is presented. The obtained results confirm the effectiveness of the proposed design of a high speed paddle mixer to obtain high-quality modified dry building mixes at a minimum rate of heterogeneity of the mixture, as well as other indicators to measure the quality of the final product, diagrams of dependence of inhomogeneity coefficient of structural and technological parameters of the mixer are given. Rational values of the main design and technological parameters of the mixer for the production of dry building mixes are given.
Numerical simulation of perimeter drainage system considering peat water permeability change over time
Authors: Nikitin A V , Zaborskaya O M 
Published: October 2020

Abstract
A reliable forecast of water depression in waterlogged areas depends on the due consideration of specific peat properties: a considerable change in the water permeability of peat once water hydrostatic uplift is removed, clogging over time, decomposition and other factors. The article presents an example of numerical simulation in Plaxis software of a perimeter drainage system, where groundwater level has been monitored for 1 year. Piezometers were installed on site at the distance of 7, 17 and 30 m from the drain pipe of a building under construction. Deformation-strength properties and filtration properties of peat were determined on samples taken from excavated pits. Besides, the samples were tested using filtration tubes to identify changes in water permeability of peat over time and depending on the amount of water filtered through peat. The survey took 90 days at the ambient temperature of 6 to 12 °C, which allowed avoiding rapid peat decomposition. The laboratory test results have shown that water permeability of natural-state peat samples has decreased by a factor of 2.7 to 3.1 with 450 to 580 liters of water filtered. The deviation of the design groundwater level calculated in Plaxis from its actual position did not exceed 0.07 m. Numerical simulation with due consideration of decreased water permeability of peat over time allows obtaining forecast results closer to the actual groundwater level.
Calculation of energy parameters of fixed drum concrete mixer with helicoid-type blades
Authors: Nesmyanov N P , Matusov M G 
Published: October 2020

Abstract
Currently, one of the most important areas in the construction industry is the production of high-quality concrete and construction mixes used in the manufacture of reinforced concrete products and structures, road, foundation, monolithic works, as well as used in the laying of bricks, blocks, etc. Concrete mixes are able to ensure high quality of the resulting products and structures when solidified. The scope of their use is the most extensive of all building materials, and production volumes are among the largest. The practice of using concrete in world and domestic construction has shown that it is effective, i.e. it has a number of advantages over new types of building materials, provides high productivity during construction work, is universal and easy to obtain. Initial components for the production of concrete are very common, easily accessible and transportable over long distances, which allows for the production of concrete mix in remote locations using mobile plants. To date, the enterprises of building industry is the production of equipment of various designs and principles of operation used for mixing. In the construction industry, a variety of mixing machines with both advantages and disadvantages have been used in the production of concrete mixes.
Use of glauconitic sand as a filler in the concrete mixes production
Authors: Botsman L N , Lunev R S , Ageeva M S , Nerovnaya S V 
Published: October 2020

Abstract
In recent years, any production tries to minimize labor costs by automating processes. Because of the high rate of automation, machines have come to replace people. In addition to reducing the share of human labor and increasing machine labor, any manufacturer seeks to reduce the cost of raw materials, which contributes to the search for new solutions in the use of old materials. Russia’s natural resource base is quite diverse, with special attention paid to the processing of technogenic waste and the creation of resource-saving technologies. Waste generation occurs at all stages of the movement of raw materials: from the moment of its extraction, when it is still a natural resource, to the end of operation of the product made from it. Waste dumps are a rich source of raw materials for the construction materials industry, as many of them are close to natural raw materials in their composition and properties. The complex physical and chemical composition and structure of waste from a number of industrial productions allow considering them as a real raw material base for the construction materials industry. The paper describes the principles of selecting the composition of concrete on glauconitic sand. Glauconitic sand is a waste product, which is why its use reduces the cost of concrete mixes and products made from them.
Stabilization of metallurgical slug from arc steel-making furnaces
Authors: Bodyakov A N , Meshkova K V , Dukhovny G S 
Published: October 2020

Abstract
At the present time the deficit of stone construction materials for transport construction points to the need for improving the range of used materials. The experience of motorway construction in economically advanced countries shows that the deficit of materials and construction costs can be significantly reduced through extensive use of industrial wastes. One promising avenue of researches is the use of metallurgical production wastes. Main methods on the prevention of slag decomposition by its stabilization are considered. The principle of increasing the stability of stone slag materials by adding a stabilizer to the steel-making slag composition during slag removal from the arc steel-making furnace, ensuring slag stabilization and prevention of the silicate decomposition after cooling, is established. Processes of the slag structure formation during its stabilization are studied. Processes of crystallisation and change of structure of dicalcium silicate are shown. The decomposition of steel-making slag can be prevented by adding a chemical stabilizer into its composition. It is established that a stabilizing agent shall consist of metallurgical production wastes that allows to fully stabilize slag and keep high-temperature modifications of belite in it when cooled. The possibility of obtaining crushed slag with a stable structure achieved by a chemical stabilization of melted slag is shown.