The article discusses the use of simplex methods of experiment planning to determine the optimal composition of composite building materials. Composite building materials are multicomponent systems, so their properties depend on a large number of factors that are diverse in nature and influence. The use of orthogonal plans is not able to adequately describe experimental data with a wide range of varying factors. Therefore, the article proposes to use simplex-lattice Scheffe's plans. A complete third-order model was developed to determine the optimal composition of the filled cement composite, and a regression equation was written. The adequacy of the equation was confirmed at the control points of the plan using the Student's criterion. The proposed planning method can be used to optimize the composition of multicomponent systems.

Keywords: multicomponent system, optimization methods, composite building material, experiment planning, simplex plans, Scheffe's polynomial, regression equation

This paper presents the results of experimental studies on the development of a chemical additive for concrete and mortar mixtures to establish a modifying effect. A chemical additive was developed - a multifunctional cleaning agent - “LOC”, in order to establish its modifying effect for concrete composites. The results of the experimental studies confirm the effectiveness of the chemical additive under study as a modifier. Composite material samples modified with the developed product show higher technical characteristics: the obtained BC samples correspond to the concrete grade for workability - P3, when the standard sample has a grade - P2, the compressive strength of the control BC samples, with a chemical additive - ""LOC"" in an amount of 1%, increases by 28%, the established optimal dose of the additive being developed - Ministry of Emergency Situations - “LOC” for Bx and mortar mixtures is 1%, which guarantees its economic efficiency.

Keywords: concrete composite, modification, surfactants, cleaning agent – “LOC”, anionic and nonionic surfactants, modifier, development, chemical additive, plasticity, strength, water absorption

The article examines the application of the method of mathematical planning of an optimal experiment in determining the strength characteristics of reinforced soils. For the analysis, a multicomponent soil system was studied, consisting of unsalted and saline soils reinforced with bitumen with cement additives and surfactants. During the planning of the experiment, factors affecting the strength characteristics and their levels, as well as the intervals of variation of factors, were determined. As a result of solving the problem, mathematical models of adhesion and angle of internal friction of reinforced soils were obtained. Based on the obtained regression equations, the main conclusions were drawn.

Keywords: stabilized soils, complex soil strengthening, experiment planning, complete factor experiment, mathematical model, regression equation

To implement effective adhesion of reinforcement to concrete, a large number of different types of periodic reinforcement profiles have recently been developed, the control of geometric parameters of which presents serious difficulties and allows for a high probability of measurement error. The urgency of the problem is due to the need to improve methods for measuring the geometric dimensions of reinforcement with a complex periodic profile in order to increase the accuracy of results along the entire length of the rod, the ability to measure the angles of inclination of axes, protrusions and dents, identify places of geometric stress concentrators to ensure the necessary quality of the finished product, reliable adhesion of reinforcement to concrete, increase the durability of reinforced concrete structures and products. The paper proposes a new method for measuring geometric parameters based on removing replicas from the surface of the reinforcement in different sections along the length of the rod. The analysis of prints presented in an expanded, flat form is carried out using counting and measuring devices, which significantly improves the accuracy and comparability of measurements, including angular dimensions. The use of modern optical devices and software for them helps to reduce the time for determining and visualizing geometric parameters, and improve measurement accuracy, which is measured in microns. The analysis of the obtained results showed an increase in the accuracy of measurements by removing replicas of geometric parameters of samples by 10-16.5% compared with traditional control methods. The developed method simplifies the measurement process, allows the use of alternative measuring instruments, a combination of calculation and instrument measurement methods.

Keywords: reinforced concrete products, profiles of reinforcing bars, methods of controlling geometric parameters, method of removing replicas, improving accuracy, reliability and comparability of measurements

The paper investigates the possibility of obtaining a luminescent material by heat treatment of phosphogypsum at a temperature of 800 degrees Celsius. It is shown that it is not enough to achieve the result of heating the system to a given temperature, the luminosity of the samples is practically absent.For phosphogypsum subjected to heat treatment at a temperature of 800 degrees Celsius for 60 minutes, it was found that images obtained in the presence of 50-150% moles of citric acid showed the most pronounced luminosity. The luminosity of samples with starch in the amount of 50-75 mol% was worse (by about 50%). The use of coal as a reducing agent under given conditions led to the formation of samples with the lowest luminosity. An extreme change in the dependence of luminosity on the amount of the introduced reducing agent with maxima of 25-75% (mol.) was revealed. It is suggested that the luminescent ability of the reduced phosphogypsum is associated with the formation of the composite material calcium sulfate/sulfide.

Keywords: heat treatment mode, luminescent material, phosphogypsum recycling, reducing

The study of the influence of the number of layers of glass composite pipe on dynamic loading, including operation in seismically active areas, is conditioned by compliance with the requirements of the latest documents in the field of construction standard control. Mechanical characteristics of glass composite pipe depend on elastic and strength properties of glass fibre, silica sand and binder, their ratio and bonding strength between layers. The key parameter of glass composite pipe compliance with the given requirements is ring stiffness. The strength of the composite material is determined using the rule of mixtures. The properties of the glass composite pipe using the rule of mixtures are determined. The influence of the number of layers of glass composite pipe on its elastic-strength properties is considered. The experiment with uniaxial compression of the pipe link is simulated in Midas GTS NX software package. The maximum load at which the sample reaches 5% deformation was determined. According to the results of the study, it was obtained that the best elastic-strength and operational properties have three-layer composite structure.

Keywords: glass composite pipe, layer scheme, earthquake resistance, continuous winding method, elastic-strength properties

The work is devoted to an urgent problem - the development of automated process control systems for the production of bricks with improved characteristics. The purpose of the article is to define and systematize the tasks of automation of brick production control systems, to develop both an algorithm for managing brick production and a generalized structure of automated control systems for brick production, and the tasks of the work are: optimization of control automation levels that determine the generalized structure of automated control systems for brick production, determination of information collection subsystems corresponding to the stages of brick production, and development of their structures, the choice of basic measurement tools for information collection subsystems. The results of the work are: systematization of requirements for modern automated process control systems, development of an algorithm for controlling technological processes and a generalized structural scheme of automated process control systems for brick production, development of information collection subsystems for the developed automated process control system, development of the structure of a local automated process control system in brick production - brick drying. The developed technical solutions can be recommended for control automation in various industries.

Keywords: brick production, technological process, drying, firing, control algorithm, automated control system, structural scheme, information collection subsystem, single-channel circuit, multi-channel circuit, measuring circuit, four-arm bridge circuit

The aim of the present work is to investigate the residual strength behavior of concrete reinforced with straight fibergalss fiber at levels of 0.8%, 1.2% and 1.6% and compare to hooked end steel fibers reinforced concrete same concentation. The laboratory tests were determined according to SP 297.1325800.2017 and reviewed literature. Test sampels was 100x100x400 with cut 17 mm in low beam in center. The residual strength behavior of Fiberglass reinforced concrete (FGRC) appeared to be comparable to SFRC, where the increase of fibers volume ratio cause the increase in prepeak and post-peak parameters of concrete. Nevertheless, the type of fibers influences much this dependency. Сoncrete mix composition was selected on the basis of compressive strength of control samples 37.5MPa. Tests were carried out to determine the crack resistance of fibre concrete on fibreglass fibre. Fibre F1 tested in this work showed a high result of extreme values of residual strength 36.3% higher than anchor fibre and 50% higher than corrugated fibre, this may be due to a more stable bond with the concrete matrix. The work resulted in concrete with crack resistance classes from Bft3= 2,5b to 6с. This study is a practical basis for the theoretical study of the effect of fibreglass fibre on the physical and mechanical characteristics of concrete.

Keywords: fiberglass fiber, FGRC, CMOD, pullout strength, analise, composite, residual strength

The work deals with the results of research on the influence of complex mineral additive: chemical water treatment sludge with burnt rock or fly ash or gaize. The rational content of chemical water treatment sludge in the complex additive was determined to be 50%. The relationship between compressive strength, flexural strength and W/C ratio, bettwen the flexural strength, E-modulus and the compressive strength were obtained. Complex mineral additive into fine grain concrete does not lead to a decrease in flexural strength and does not increase the E-modulus of fine grain concrete. The average range of the E-modulus of fine grain concrete with complex mineral additive practically coincide with those in Russian National Standart 56378 - 2015. The use of chemical water treatment sludge for fine grain concrete at amount of 20% of complex additive of a rateable composition instead of part of the cement provided to increasing of compressive strength at an equal W/C ratio relatively to the non-additive standard by 7 - 20%, and the flexural strength by 12 - 22% .

Keywords: miniral additive, tensile strength, modulus of elasticity, gaize, fly ash, burnt rock, chemical water treatment sludge

In conditions of high cost of construction materials, machinery, equipment and services it is necessary to consider the possibilities of increasing economic and energy efficiency of erected buildings. One of the options for solving this issue is the use of energy efficient products in construction. The article will consider one of the innovative thermal insulation materials - PIR boards.

Keywords: construction, thermal insulation, thermal insulation material, polyisocyanurate foam, frame-monolithic construction, wall panels, reinforced concrete, thermal calculation

Engineering preparation of the territory for the construction and development of a residential complex is a difficult task. In the development area, fluctuations in the groundwater level are possible due to natural processes - flooding of the territory or during operation due to man-made processes. The work presents the results of the survey and assesses the impact of future construction on the hydrological situation of the built-up areas. Materials from engineering-geological surveys of the composition of soils in the lake water area and the building area were studied in order to determine the possibility of using alluvial soil from the lake for engineering preparation of the territory.

Keywords: engineering and geological surveys, urban development, alluvial soil, engineering preparation of the territory

The results of a study of the influence of shrinkage deformations on the basic physical and mechanical properties of concrete are presented depending on various production and technological factors. The research methodology took into account the choice of the period of aging concrete in a dry, hot climate to study the influence of physical processes in concrete on its physical and mechanical properties. The influence of shrinkage deformations on the strength characteristics of concrete was studied. an increase in the intensity of mass transfer processes between concrete and the environment leads to an increase in destructive shrinkage deformations, mainly plastic shrinkage of concrete, which lead to changes in the structure and physical and mechanical properties of mature concrete. The consistency of the concrete mixture also influences the amount of strength reduction. with a greater value of plastic shrinkage of concrete, its compressive and tensile strength in bending decreases. the destructive effect of plastic shrinkage on concrete caused depends on a number of technological factors (consistency of the concrete mixture, w/c, temperature and humidity hardening conditions, etc.).

Keywords: curing period, mass transfer processes, plastic shrinkage, concrete structure, concrete strength, reconstruction, buildings and structures

The article examines the application of properties of polyethyleneimine (PEI) and polyacrylic acid (PAK) polycomplex composition for soil strengthening. During the studies, the ratio of PEI and PAA (by dry weight) was established, at which the reagents most fully enter the complexation reaction. The polycomplex composition of the optimal composition was used to strengthen the soils of some varieties. When studying the properties of hardened soils, dependencies were obtained: the ultimate strength of the hardened soil on the relative humidity and the thickness of the layer of hardened soil on the consumption of complexing reagents. The paper concluded that the use of polycomplexes for soil strengthening is promising.

Keywords: polycomplex composition, soil strengthening, polyethyleneimine, polyacrylic acid, impregnation method, dedusting, optimal humidity

A technological scheme for the production of biostable materials based on monoethanol-modified (N→B)-trihydroxyborate (MEATHB) stems of Sosnovsky's borer and polyurethane binder has been developed. This technological scheme differs from the traditional one in that it includes the process of plant raw material modification to ensure its biostability. The paper presents the results of determining the thermophysical properties of the obtained thermal insulation boards, as well as the results of assessing their biostability. The obtained results correspond to the current requirements for thermal insulation materials. The paper analyzes the main stages and processes necessary to create a high-quality and environmentally friendly product. The main types of plant raw materials used in the production of thermal insulation materials are considered, as well as the features of technological processes associated with its processing and formation. In addition, the advantages of using plant materials in the production of thermal insulation materials from the point of view of ecology are presented.

Keywords: technological scheme, biostable composites, Sosnovsky's borer, modification, biostability, monoethanolamino(N→B)-trihydroxyborate, heat-insulating material

In the article there was considered a possibility of off-grade materials utilization for making fine concrete with a multicomponent complex additive applied. Use of fine sands as raw material for fine concretes is actual for many regions in Russia because of deficiency of sands of necessary fineness modulus. There was considered the issue of utilization of fine sand and stale cement for reducing cost (loss), widening materials’ assortment for low-rise building, and energy- and resource-saving. To achieve the assigned purpose a multicomponent complex additive was applied. The research was carried out in full correspondence with the adopted design of the fractional factorial experiment. The acquired results were subject to a preliminary analysis and processing, and consequently dependences of strength properties upon varying factors were obtained. The obtained dependences made it possible to select optimal ingredients’ proportion of the complex modifying additive in order to increase strength properties of fine concrete based on off-grade materials. It was established that the use of optimal consumption of the complex additive components allows increase strength properties by 25-30% in comparison with the reference composition.

Keywords: fine concrete, fine sand, stale cement, complex additive, fractional factorial experiment, strength

The factors affecting the strength of the interlayer bond of 3D concrete, as well as factors affecting the ability of the printer nozzle to produce a controlled concrete thread of a particular composition, which is being investigated in the process of 3D printing technology, the main characteristics of the suitability of compositions for printing on a 3D printer, requirements for rheology, hydration and strength in an uncured form, are considered 3D concrete, the main mechanical test methods for determining the adhesion strength in concrete printed on a 3D printer. The possible shapes and nominal sizes of the samples used in the methods for determining the strength of concrete are given.

Keywords: 3D concrete, anisotropy of mechanical properties, extrusion, cold connection, interfacial coupling, deflocation, thixotropy, initial static viscosity, curing, three-point bending

Increasing the energy efficiency of the construction process involves the use of materials with the lowest material intensity, including thickness, as well as with a reduced content of Portland cement clinker while maintaining or improving the technical characteristics of the products. In this regard, the use of textile concrete products, including concrete sheets, is promising. The development of a composite binder containing components that reduce nega-tive pressure in hardening concrete, and consequently shrinkage deformations and cracking, made it possible to obtain products with the following waterproofness indicators: determined by the ""wet spot"" method: 1.2 MPa; with a filtration coefficient of 5-7×10-11 cm / s; the concrete waterproof grade W12

Keywords: textile-concrete, concrete web, water resistance, shrinkage during hardening, cracking, fine concrete

The article presents a model for the formation of a thermodiffusion layer on steels. Thermodiffusion coatings on 45 steel and HVG steel were obtained by a chemical-thermal method in a powder mixture. Studies of layered X-ray diffraction phase and microrentgenospectral analysis of the studied coatings have been carried out. on steel. The obtained results of X-ray diffraction and microrentgenospectral analysis of diffusion coatings confirm the correctness of the model of formation of the diffusion layer and the theoretical prerequisites outlined. The results of the study can be used in the preparation of mixtures for thermal diffusion saturation.

Keywords: diffusion layer, diffusion chrome plating, diffusion coating

Clinker tiles are one of the most popular types of roofing materials. Compared to other roof coverings, clinker tiles have higher strength, resistance to aggressive environments and aesthetic indicators. The relevance of the production of clinker tiles due to the fact that at present architects and builders are showing great interest in such an elite roofing material such as clinker tiles. However, the main trends in the production of ceramic tiles are to increase its strength while reducing weight by reducing the thickness. The conducted research has shown that the production of clinker tile on the basis of argillites Nekrasovskogo deposit is possible at a fractional composition of 0-0,08 mm, 0-0,05 mm and firing temperature of 1050 ˚C.

Keywords: argillite, tile, clinker, research, chemical composition, mineral composition, ceramic products, properties, technology

This paper is aimed to present the produced compositions of bitumen- mineral open (BMO) mixtures for the Novoselovsky district of the Krasnoyarsk Territory. The Federal Road M53 runs through the area and in this district in particular it is characterized by steep ascents and descents. To ensure the required adhesion properties of road asphalt concrete pavements with car wheels for thepurpose of traffic safety in the area under study, the construction of rough wearinglayers or toppings from BMO mixtures has been suggested. Compositioncalculations were carried out using local mineral materials and BMO mixtures,after which test samples were prepared in laboratory conditions. It has beenestablished that the developed BMO mixture compositions meet all regulatory requirements. Recommendations are developed for the factory technology ofpreparing bitumen-mineral open mixtures and the design of rough wearing layers.Instructions for technical control during the preparation of BMO mixtures aregiven. The Road Repair and Construction Department of the Novoselovsky districthas already introduced the obtained compositions into the practice of road construction.

Keywords: bitumen-mineral open mixtures, rough wearing layers, toppings, roads, asphalt concrete, bitumen, crushed stone, sand, compositions, technology

Expert work has been carried out to determine the causes of the low adhesion strength of hand-molded ceramic bricks with Maxpol colored masonry mortar. The tests were carried out in accordance with GOST 24992 on 6 series of samples aged 7 and 28 days of hardening. The adhesion strength in the series of tested samples at 7 days of age, which were washed with running water, is 54% higher compared to the samples that were not treated.The compressive strength of Maxpol colored masonry mortar meets the requirements of technical specifications 23.64.10-001-79211444-2017 . The adhesion strength in the masonry meets the requirements of technical specifications only in a series of hand-molded bricks that have been treated with running water at the age of 28 days.

Keywords: ceramic brick, colored masonry mortar, adhesion strength, compressive strength, separation area

Calculation and analytical studies have been carried out on the influence of the duration of operation of nuclear power plants (NPP) when extending their service life on radiation and radiation-thermal changes of volume and compressive strength in serpentinite concrete of “dry” radiation-thermal shield (hereinafter referred to as “dry” shield) of Water-Water Energetic Reactors (WWER /VVER) different power. Concrete based on typical serpentinite aggregate from the Bazhenov deposit, used for the production for concrete of “dry” shield, is considered. It has been established that with increasing operating duration, radiation changes of the serpentinite concretes in “dry” shield of NPPs with VVER will generally increase monotonically and, in terms of volume changes, can become commensurate with or even exceed permissible values. In this regard, radiation changes in the concrete of «dry» shield should be taken into account when extending the operating life of nuclear power plants. It has been shown that radiation changes in the concrete of “dry” shield for NPPs with VVER-440 are 2 - 4 times more significant than of “dry” shield concrete for NPPs with VVER-1000. Radiation changes in the concrete of "dry" shield increase with decreasing average operating temperature. Thermal changes in serpentinite concretes of "dry" shield when exposed to operational and emergency temperatures increase with temperature and make a significant contribution to radiation-thermal changes in dry-shield concretes. The results obtained can be used to establish the permissible period for extending the operation of nuclear power plants with reactors of the VVER 440 and VVER-1000 types based on radiation-thermal changes in serpentinite concrete of "dry" shield.

Keywords: radiation, thermal, radiation-thermal changes, serpentinite concrete, “dry” radiation-thermal shield, water-water energetic reactors, extension of the operating life of NPP

The urgency of creating systems to stabilize and strengthen soils is due to the need to build buildings, structures and roads in regions where clay soils, as well as loams and sandy loams are widespread. The article formulates the main technological and technical requirements for stabilized soils. The principal possibility of applying a complex modification of the soil by introducing a composite composition of quicklime and finely ground granulated blast furnace slag in combination with mechanical compaction is considered. The results of studies of soil modification by composite composition are presented, the purpose of which is to make the soil suitable not only for the installation of anti-filtration curtains in soils during the development of pits, but also for foundations and basements. The results of studies of the properties of stabilized soil are presented.

Keywords: unstabilized soil, soil modification, loam, quicklime, ground slag, analytical optimization

The main properties of slag-alkaline binders were studied to determine their optimal composition. The possibility of controlling the properties of binders developed on the basis of phosphorus and blast furnace slag by introducing corrective additives into the aluminosilicate component of slag-alkaline binders, as well as by changing the type of alkaline component, has been experimentally proven. The conducted studies confirm the effectiveness of the use of sulfate-containing alkaline components for the production of slag-alkaline binders. As a result of the conducted experiments, slag-alkaline binders with an activity of 30 to 110 MPa were obtained. The possibility of regulating the properties of the developed slag-alkaline binders has been established. The required binding strength is achieved by adjusting the composition of the aluminosilicate component by introducing additives and the type of alkaline component.

Keywords: alkali-silk binders, slags, optimal composition, basicity, chromium peak, construction materials, reconstruction, work technology

There has been studied the influence of gypsum-cement-pozzolana binding agent composition on its key strength properties. The study was aimed on the definition of such consumption of gypsum-cement-pozzolana binding agent components, which could allow maximum ultimate compression strength with minimum consumption of Portland cement provided. As the components of gypsum-cement-pozzolana binding agent, there have been used plaster, Portland cement, and the most wide-spread in the region pozzolana additive. An experiment design was developed to fulfil the work. The research was held in correspondence with the design, and the acquired results made it possible to estimate and analyze descriptive statistics, and expose the influence of components on strength properties of gypsum-cement-pozzolana binding agent. In the course of the analysis it was specified that pozzolana additive consumption factor, and interaction of consumptions of plaster and Portland cement exert a positive influence on strength properties of gypsum-cement-pozzolana binding agent. There have been acquired mathematical models of the influence of gypsum-cement-pozzolana binding agent components consumption on ultimate compression and bending strength of gypsum-cement-pozzolana binding agent. The said model allow forecasting gypsum-cement-pozzolana binding agent composition to have a desired ultimate compression strength. An optimization was carried out and there was acquired a composition of gypsum-cement-pozzolana binding agent with maximum ultimate compression strength with minimum consumption of Portland cement provided.

Keywords: gypsum-cement-pozzolana binding agent, optimization of composition, ultimate strength, experiment design, descriptive statistics, superposed diagram, correlogram, ternar chart