Assessment of influence of speech intelligibility and reverberation time on the quality of acoustics Determination by theoretical method and computer simulation method of reverberation time in the modern audience and the audience, built more than 10 years ago. Determination of sound absorption coefficients of surface materials in both classrooms. Modernize of classrooms using wood fiber panels to increase sound absorption and reduce reverberation time. As a result, the reverberation time of the upgraded audiences has become less than one at all frequencies. This ensures good speech quality and efficiency of the educational process.

Keywords: acoustics, classroom acoustics, reverberation time, speech intelligibility, sound absorption coefficient, computer simulation, wood fiber

The article presents the analysis of the properties of local fine aggregates, their influence on the characteristics of the concrete, and also presents the impact of screening crushing when it is introduced into the mixture in various proportions on the strength of concrete

Keywords: Concrete, screenings of crushing, construction sand, experiment, grain composition, concrete strength, small aggregates

The structure of measuring stands of ultra-high-frequency installation of drying and baking of bricks is considered. The creation of a practical microwave installation is determined by the creation of measuring stands at a low power level, by working on electrodynamic models and by creating appropriate laboratory installations of a high power level. The measuring stand of the described structure allows to check the matching characteristics of all waveguide elements of the feeder chain, adjustment of waveguide tees, and the development and tuning of the energy input units to the microwave chamber of the experimental setup. In the laboratory installation it is proposed to use the industrial generator KIE-5, operating at a frequency of 2.45 GHz with a maximum output power of 5 kW and a waveguide ferrite circulator. The maximum power of such an installation differs only 10 times from the power of the experimental setup. This makes it possible to reliably estimate the electrical strength and heat release of the experimental unit assemblies from the results of laboratory studies.

Keywords: "izmeritel'nyy stend, sverkhvysokochastotnaya ustanovka, kirpich, sushka, obzhig, moshchnost', struktura, elektrodinamicheskoye modelirovaniye, eksperimental'naya ustanovka measuring stand, super-high-frequency installation, brick, drying, firing, power,

In the article the scheme of the measuring stand of the device model for determining the part of the energy distributed from the generator, the scheme of the measuring stand of the model for measuring the standing water coefficient (VSWR) and the measurement of the transient resistance are presented. The best results are obtained by a partition consisting of two metal plates overlapping the path both above and below the clay layer. So, with a clay humidity of 4%, the total attenuation was 14.4 dB (-6.1 dB without a partition), and at a humidity of 16% -35 dB (-18.4 dB without a partition). There is an increase in attenuation of approximately two times compared to the case without a partition for both dry and wet clay, but the amount of attenuation is insufficient. To increase the attenuation in model 2, two consecutive resonators were created. But the attenuation in this case increased insignificantly in comparison with one resonator. It is obvious that two resonators are upset because of mutual influence on each other. Therefore, it is proposed in a real installation between these two resonators to place a section of a waveguide of nonresonant length with an absorber that will eliminate the coupling between the resonators.

Keywords: measuring stand, super-high-frequency installation, brick, drying, firing, power, structure, electrodynamic modeling, experimental setup

This article considers the use of asphalt as the main component of the cold organo-mineral mixture intended for patching of city streets and roads during the off-season. The General characteristics of mixtures and their components are given, the pros and cons, as well as the possibility of their application are given. As a powder emulsifier and activator, it is recommended to use lime-containing waste (calcium oxide hydrate) of the chemical industry.

Keywords: organo-mineral mixture, asphalt granulate, asphalt concrete, road construction, binder, lime-containing waste

When organizing work on the territory of sanitary protection zones, it is necessary to take into account that the SPZ is already a territory with elevated levels of exposure, which may require the use of additional means of individual and collective protection. Meteorological parameters are important factors affecting the extent of the impact of the work on human health. The article presents a comparative analysis of the concentration of suspended substances in the workplace, depending on meteorological parameters.

Keywords: sanitary protection zone, hazard class, industrial enterprise, construction, reconstruction, ecology, atmosphere, labor protection, non-stationary workplace

This article presents the results of studies on the effect of the erbium chelate complex on the processing of secondary raw materials from polyethylene terephthalate (PET).

Keywords: polyethylene terephthalate, recycling, extrusion, polyisobutylene, chelate complex of erbium.

A comparative analysis of the methods of heat engineering calculation and an assessment of the efficiency of heat exchange in frame-panel housing construction are presented.

Keywords: Skeleton-panel housing construction, air permeability, heat exchange efficiency, heat and moisture regime

The article is devoted to the study of the problem of determining the mechanical properties of vibrating centrifuged concrete with a combined aggregate and fibrous additive, which was basalt fiber. Experimentally obtained data on the optimal consumption of disperse fiber. The dependence of the strength properties of concrete with a combined aggregate on the amount of fiber additive added is graphically presented. Also graphically shows the increase in the speed of the passage of an ultrasonic wave in the body of concrete when determining the prismatic strength. It was found that the presence of porous particles in a concrete mixture facilitates the directed distribution of mineral fibers along the section of the concrete ring. This, in turn, leads to an increase in the fracture toughness of the material. The conclusion is made that the joint introduction of porous and fibrous additives into the concrete mix determines the production (at the same cement costs) of high-strength concretes with an increased crack resistance, as evidenced by the data on the displacement of the boundaries of microcracks formation in the direction of their increase.

Keywords: structures and products of annular section, centrifuged concrete, vibrocentrifuging, mechanical properties of vibrating centrifuged concrete, combined aggregate, fiber additive, basalt fiber, prismatic strength

The advantages of using self-compacting concrete in the technology of precast reinforced constructions that are manufactured on stands with a travelling shuttering were considered. Considering the significant heat losses on the heating of products in this technology, concretes have been studied that harden at low temperatures. It was shown that self-compacting concretes with consumption of 330-450 kg / m3 gaining strength in compression of 20-35 MPa for 16-20 hours at low temperature heating.

Keywords: self-compacting concrete, stand technology, travelling shuttering, disperse filler, superplasticizer, heat treatment, strength

The article deals with the effectiveness of high-strength concrete for the design of concrete columns on the example of 20-storey residential building in Rostov-on-Don. The results of the ground floor columns calculations for different types of concrete strength are presented. The columns are presented in two variations. The first variation is 600x600 B25 from the second underground floor to the tenth floor and 500x500 B25 from the eleventh to twenty-fifth floor. The second one is 500x500 B60 from the second underground floor to the seventh floor, 400x400 B60 from the eighth to the eleventh and 400x400 B25 from the twelfth to the twentieth floor. The analysis of the study results showed the technical and economic efficiency of the use of high-strength concrete (in particular, concrete class B60) due to increasing the strength characteristics of the compressed elements. This is also due to reducing the cross-sectional size and weight of the columns, saving reinforcement, causing a reduction in the cost of elements as a whole.

Keywords: high-strength concrete, compressed elements, construction of tall buildings, columns, Lira-SAPR, calculation of structures

It has been shown that waterproofing mastics (WM) should have increased indicators of water, wear and heat resistance, adhesion to surfaces, environmental friendliness, durability, etc. The relevance of reducing the prime cost of WM with the simultaneous improvement of their properties, due to the introduction of mineral fillers of natural and technogenic origin, as well as wastes of various industries, in polymer- bitumen compositions . The possibilities of introducing secondary products of the petrochemical and rubber technical industry into the composition of the WM, as well as the possibility of using asbestos, kaolin, montmorillonite, karelite and other fillers are generalized. It has been experimentally proved that the use of polymeric plasticizing and rubber wastes, as well as mineral components in the composition of WM, made it possible to obtain a composition having advantages in strength of adhesion and conventional strength up to 3 times, in water absorption up to 5 times, in relative elongation up to 7.5 times, in comparison with regulatory requirements.

Keywords: waterproofing mastic, roofing, polymer-bitumen binder, production waste, mineral filler, cost, strength, water absorption, heat resistance

The possibility of obtaining quick fixing glue of C0-C2 classes on the basis of gypsum-aluminous expanding cement modified with Portland cement is shown. It was found that the strength of adhesion to the base and the amplitude of deformations during hardening of the quick fixing glue based on the MGGRC essentially depends on the ratio of GC: G: PC in the binder composition, and the direct relationship between the dosage of the PPP in the adhesive composition and the strength of adhesion to the base is not traced. It was revealed that the PPP and VMD positively influence the early strength of adhesion to the base, but at the age of 28 days the influence of the VSD becomes negative. A decrease in the strength of adhesion to the base was found with an increase in the tensile strength of the adhesive for bending. There is no direct relationship between the adhesion strength and the amplitude of glue deformations during hardening.

Keywords: dry building mixes, bond strength, hypoglycous expanded cement, fast fixing glue

The possibility of obtaining fast-hardening levelers for the floor (monolithic screeds) with a compression strength of more than 20 MPa based on gypsum-alumina expanding cement modified by Portland cement (MGRC) is shown. It is established that the kinetics of the compressive strength is mainly determined by the ratio of HZ:G:PTS МGGRC in the composition, the superplasticizer (SP) and esters of methyl cellulose have a negative impact on the buildup of strength in the early period and the value of design strength, as silica fume does not affect the kinetics of strength in the early period and the project age. The ratio of the limits of tensile strength in bending and compression influence internal structural stresses caused by the mismatch between the extension and strength growth in time due to different additive effects of SP and cellulose ethers on the kinetics of formation of hydrocortamate and calcium hydrosilicates.

Keywords: dry mortar, adhesion strength, gipsovoloknistyh expanding cement, glue quick fix

The paper presents an analysis of the processes of formation and processing of vegetable waste. An assessment is given to the existing ways of processing woodworking wastes and their inefficiency is justified. A new kind of resource and energy-saving grinding set of disk mills is proposed. On the basis of the analysis of the results of experimental research, the effectiveness of the use of the proposed method for the production of wood fiber is substantiated.

Keywords: abrasive set, grinding, efficiency, wood-fiber semi-finished product, specific fiber surface, wood pulp, defibrator, refiner, refiner, knife grinding

The analysis of the experimental data is carried out and the works devoted to the account of the influence of the compressive pressure factor with the purpose of optimizing the parameters of the centrifuged products of the annular section at the compaction stage are studied. The number of rotations of the mold at the compaction stage is calculated for different values of the compressive pressure. A statistical analysis of the regression equations obtained is performed using three criteria: homogeneity of variances, significance of coefficients and adequacy, which was tested with the help of Fisher's criterion. The data were statistically processed using the Mathcad program, which allowed obtaining regression equations in the form of polynomials of the second degree with specific values of their coefficients. Graphic interpretation of mathematical dependencies is constructed. The calculated dependencies are obtained that allow to determine the required number of revolutions for any required diameter and wall thickness of annular centrifuged products for a given fixed value of the compressive pressure in concrete.

Keywords: compressive pressure, centrifuged products of annular section, response function, factor of variation, least squares method, regression equation

At present, progress in building materials science and the construction industry is gaining in importance. New technologies provide high quality products, its environmental safety, efficient use of raw materials, saving resources. The creation of high technologies is possible only with the use of the latest achievements in physics, chemistry and other basic sciences. To date, the most promising are nanotechnology.

Keywords: nano-concrete, natural raw materials, additives, macro-reinforcement, fiber, nanostructure, crack resistance

The properties and main characteristics of the large-tonnage waste of industry - hydrolytic lignin, as well as the direction of its rational use are considered. The results of an experiment on the effect of the lignin of the Kosivinsk hydrolysis plant on the main properties of the cement-sand composition are presented. It is shown that the addition of hydrolytic lignin in an amount of 15-20% by mass in exchange for the binder will yield a building material with a mark of average density D1900-D2000 and a class of compressive strength B5-B7.5.

Keywords: hydrolytic lignin, waste, low-rise construction, wall material, secondary raw materials, utilization

Possible unfavorable changes in roofing bitumen mastics (RBM), such as shrinkage, cracking, aging, insufficient adhesion, etc., which occur under the influence of external factors, are summarized. The limitations of the chemical modification of RBM and the advantages of physical methods, in particular microwave effect, are shown. The possibilities of using microwave energy in the processes of extraction of the bitumen component, during its dehydration and activation, during the synthesis, drying and intensification of the reactions of obtaining modifiers and their combination in bitumen compositions are systematized. The prospects of using microwave in the activation processes of mineral fillers, as well as the application and repair of bituminous coatings, are revealed. It is shown that conformational and intermolecular changes under the influence of microwave can lead to an increase in water resistance, strength, combined with elasticity, thermal and frost resistance, and also the durability of RBM.

Keywords: roofing mastic, bitumen composition, filler, chemical modification, physical methods, microwave, drying, activation, interface, strength, water resistance, elasticity, adhesion

The article presents the results of studies of the surface characteristics of textile materials used for personal protective equipment and in construction projects, taking into account the climatic conditions of their operation. The features of their optical and color properties in the open industrial area in the cold period, which form the elements of General industrial safety, are revealed. The influence of low temperature and humidity on the structure and surface properties of materials of the different fibrous composition is experimentally established. This leads to the correction of optical parameters of various objects on construction and industrial sites, determining the conditions of sufficient or limited visibility. The results are adapted to solving the problems of designing environmental spaces of construction projects and the development of innovations in textile materials science and means of individual safety in the industry.

Keywords: fibrous materials, design and evaluation of construction projects, environmental and industrial safety, design of environmental spaces, innovations in textile materials science

in this article we consider the thermophysical and sound-physical properties of window blocks of various designs used in buildings and structures. For practical research, some dependencies are offered that allow us to describe the various properties of window blocks in wooden, metal and plastic bindings

Keywords: thermophysical properties, sound-physical properties, translucent fences, window blocks

The Algorithm and program for calculating for the strength, deformation and fracture toughness of reinforced concrete structures. It has been improved under various regimes of slightly-repeated loads on the basis of the development of scientific ideas about the effect of the own field of stresses of concrete with the EMBALIT and SP, as well as the establishment of low-cycle fatigue strength of such concretes and limits fatigue strength from the main factors. The main regularities of development of own deformations and stresses of concrete during hardening under conditions of restriction of expansion deformations and without restriction are revealed.

Keywords: design features, self-expanding concrete, embalite, calculation of strength of reinforced concrete columns, low-cycle fatigue strength, superplasticizers, embalit additive, calculation of crack resistance of reinforced concrete structures, intrinsic defor

The influence of polycarboxylate-based superplasticizers on the water-holding capacity of cements and the properties of highly mobile and self-compacting concretes has been studied. In the course of studies it was found that the water-holding capacity of cement in the presence of a specific additive reflects its potential activity and is a very important characteristic when choosing a pair of "cement-superplasticizer". Rheological activity of superplasticizer with cement concrete were estimated according to the value of the maximum shear stress of cement slurries. To assess the composition of self-compacting concrete should be used cement utilization factor in concrete, reflecting its technical and economic efficiency. Concretes with a rationally selected grain composition and dosage of polycarboxylate-based superplasticizers can achieve high strength with a minimum specific consumption of cement.

Keywords: water-holding capacity of cement, rheological activity of superplasticizer, self-compacting concrete, concrete strength, cement utilization factor

Various mineral porous components, such as expanded clay, ash microspheres, etc., are used to regulate the processes of structure formation and physical and mechanical properties of shock-resistant concrete of rigid pressing.

Keywords: Regulation, structure formation, physical and mechanical properties, ash microspheres, phase-mineral composition, X-ray phase analysis, adhesion

The parameters of the structure of the building material, including sulfur, depend on a large number of prescription and technological factors. This paper presents the experimental dependences of the average density and porosity of the sulfur composite material on the volume degree of filling, the specific surface of the filler, the concentration of the appret and the time of isothermal exposure. It is established that the dense sulfur composites obtained with silica filler with a specific surface area of 180 m2/kg, processed 30%-and 50%-s ' solution of rubber and subjected to isothermal aging for 2...3 hours

Keywords: Sulfur, silica filler size, filler, volumetric filling degree, average density, porosity, dispersion