A problem of efficient resource usage in road branch continues to be one of the most complicated issues and requires an intensification in investigation process pertaining to possibilities for production of road construction materials of low resource intensity with high physical and mechanical properties. Technogenic wastes of the Belarusian enterprises are rather various and they need a detailed investigation. Application of such methods as IR spectrometry, probe microscopy, study of of geometric characteristics of particles and fibers make it possible to determine more active centres and reveal micro-defects that influence on strength of adhesion bond at the boundary of “fiber – binder” and physical and mechanical properties of ready-mixed asphalt concrete. Nature of basalt fiber presupposes mainly physical character of adhesion interaction at the boundary of phase separation. An increase of technogenic waste activity to enhance adhesion contacts up to chemisorption level is possible only due to preliminary fiber processing which includes cleaning, removal of foreign inclusions, etching, drying, probable sorting-out and fluffing. Industrial approbation of such technological process is not possible without development of a corresponding module or a plant. Disperse reinforment causes changes in composition and technology of sand asphalt concrete. An increase in specific surface of an aggregate, necessity of uniform distribution of fiber in terms of volume determine the required need in a binder, procedure and regimes for component mixing. Grain composition of the aggregate can be represented by crush screening and natural sand of mixture of these materials. Requirements to properties of sand disperse-reinforced asphalt concrete are formed on the basis of operational conditions and layer arrangement of the material in the design of a surface dressing. The disperse-reinforced sand asphalt concrete can perform functions of a superfine protective layer, a levelling layer or a crack stopping layer which is resistant to fatigue crack formation.

The paper considers a solution of contact problem for hinged supporting node of beam floor slab (coating). The main goal is to determine a stress state of the area where a plate rests on the wall. In this case, a number of problems are solved: construction of reactive pressure diagrams in the area of direct plate and wall contact, clarification of the calculated plate span, influence of contact zone size on a value of maximum bending moment in the middle of the plate, determination of contact area at various indices of flexibility and comparison of the obtained results with the known solution of rigid stamp and elastic quarter-plane interaction. The calculation has been carried out by the Zhemochkin method, its implementation for the given task corresponds to a mixed method of structural mechanics. As an illustration, the calculation has been performed on a concentrated load applied in the middle of the plate span. In the course of the study, it has been established that when a reinforced concrete slab rests on concrete and brick walls, the contact zone reduces itself to two Zhemochkin sections. When a flexibility index is decreased that corresponds to slab support on a less rigid base, the contact area is increased, and that, in its turn, has an influence on an increase of the calculated slab span and the bending moment in the middle of the slab. In the case of an absolutely rigid plate support (flexibility index is equal to zero), the contact stresses reach their maximum value at the point of plate edge contact and elastic quarter-plane. The nature of the diagram is confirmed by an analytical dependence of contact stress distribution obtained by Aleksandrov V. M. when solving a problem of pressing a rigid stamp into an edge of an elastic wedge.

Reinforcement corrosion of marine and coastal hydraulic structures due to chloride aggression and concrete carbonization leads to a sharp decrease in structure safety. The reinforcement is subjected to a depassivation process as soon as a chloride concentration on its surface exceeds a certain threshold concentration, or the pH value in a concrete protective layer is decreased to a threshold value due to carbonation. Electrochemical reactions are realized with formation of corrosion products due to penetration of oxygen up to reinforcement surface. This leads to cracking of the concrete protective layer and decrease in reinforcement cross-section. The paper proposes a method for predicting a complex degradation of reinforced concrete structures with due account of various mechanisms of corrosion wear that allows to develop efficient methods for improvement of structure durability and maintainability which are operated in the marine environment. A methodology for forecasting of reinforced concrete service life prediction has been developed under a combined effect of carbonization and chloride aggression while using finite-difference and probability models. The paper takes into account initiation periods of reinforcement corrosion and propagation periods for conditions of Sakhalin shelf zone. Field surveys of Kholmsk and Korsakov port facilities are presented in the paper. Carbonization front and chloride content have been estimated according to depth of the concrete protective layer. The paper proposes a model that allows to determine an average period prior to repair while taking into account rate of concrete protective layer degradation caused by simultaneous action of two corrosion processes: carbonization and chloride aggression.

Theoretical and experimental investigations have resulted in obtaining an effective insulating and structural material (claydite foam concrete) that is not subjected to slump and shrinkage in the range of main grades used in construction in terms of average density D300–D700, characterized by 5–31 % greater strength and 8–27 % elasticity modulus, as well as a higher (£30.7 %) level of vapor permeability and moisture return (by 17.4–46.7 %) with lower values (by 10.0–83.2 %) of water absorption, sorption moisture and thermal conductivity in comparison with aerated concrete of autoclave hardening and foam concrete of equal density. A three-stage technology has been developed for preparing claydite foam concrete. At the first stage cement dough is prepared and if it is necessary an optimum amount of hardening accelerator (1 % CaCl2 from cement mass) and additives condensing cement stone structure (1 % Al2SO4 from cement mass ) are introduced into it, they prevent slump of a binder (foam concrete) during the subsequent hardening, and in combination with 0.5 % from cement mass “Hydroxypropylmethylcellulose УСК-200 TT” – and shrinkage of foam and claydite foam concrete during the subsequent drying. At the second stage, the binder is aerated while introducing protein-based foam agent (Laston) into the cement dough in an optimal amount (depending on the given density) 0.5–1.3 % from the cement mass; and at the third stage, expanded clay gravel is introduced into prepared foam concrete mixture (in rational amount of approximately 0.7–0.8 m3 per 1 m3 of claydite foam concrete) with continuous mixing for 60–90 seconds. Methodologies for calculation of foamand claydite foam concrete compositions have been developed; molding modes of expanded clay foam concrete with high degree of homogeneity (variation coefficient of density and strength uk £ 6.2 % in the process of manufacturing molding with layer height up to 1500 mm) have been justified that confirms efficiency of the proposed technology.

The paper substantiates scientific background for development of lubricant compositions used in moulds for concrete products with high-quality surface. It has been shown that consideration of interaction between air bubbles, lubricant and liquid phase of modified concrete is of great importance. A release agent must allow air to migrate to a certain extent and leave “formwork – concrete mix” interface. In this regard the lubricant must have low viscosity. In addition, the lubricant should give maximum hydrophobization to a mould and have minimal adhesion in respect of the concrete mix. Additives of hydrophobic substances in liquid lubricants significantly reduce surface porosity of products. Chemical plasticizing additives and, in particular, additives of polycarboxylate type substantially reduce surface tension of liquid sгж, thereby they significantly reduce work for fixing an air bubble on concrete surface and contribute to its ejection. In addition, adsorbed molecules of the chemical additives interfere with interaction of cement paste particles and mould surface. Polycarboxylate additive molecules diffuse from a diffuse layer of the concrete mix, fill capillaries in the lubricant film, reduce its viscosity, act as additives that regulate spreading of lubricant and facilitate removal of air bubbles in a surface layer. Experimental studies of the combined effect while using low viscosity grease based on vegetable oils and modifying additives have confirmed the above provisions. The polycarboxylate-based additive has made the greatest impact on reduction of concrete surface porosity and content of all types of pores in the concrete has been approximately at the same level.

The paper considers principal features and specific character of architectural design for health care institutions. Main designing stages, missions and complexities for every successive designing step have been revealed in the paper. The paper presents specific features, main stages and design approaches to designing of modern health care facilities, comfortable architectural environment of health institutions, which have been formed on the basis of the analysis of advanced international experience in the field of designing healthcare facilities. The proposed approaches are based on modern experience in designing medical buildings over the past decade in the developed countries. A special attention has been paid to obsolete methods for architecture-planning organization of healthcare facilities and modern approaches to arrangement of engineering and other systems which significantly influence on economical efficiency, quality, comfort and effectiveness of architectural environment in healthcare institutions. Every healthcare facility, every separate department are considered as unique in their essence, for this reason it is not so easy to reflect modern technological solutions and architectural tendencies. The paper contains an attempt to attract attention of architects to the complexity in designing of a building to be constructed, to find ways which will help to reach its step-by-step solution. It has been noted as well that there is a necessity to arrange interaction between an architect and a medical technologist. Modern medical departments and hospitals have been recently designed and built in the Ukraine, but they are in increasingly short number. These facilities have been constructed due to decision makers who, in spite of diverse difficulties, lack of information and specialists, lack of proper funding, etc., are trying to do their best in order to reach the modern level of desingning and construction of hospitals. So-called “typical” medical projects of 70-ies and 80-ies continue to be implemented up to now. This is certainly due to inadequate funding, but such economy has at the end rather high cost.

The paper presents a complex of laboratory and theoretical studies of physical and mechanical properties in centrifuged concrete while using samples of sectoral cross-section which are cut in layers from a finished product. A post made of concrete having B40 grade for compression strength and manufactured while using centrifugation with the help of РТЦ-5 machine. Assessment of heterogeneity across section thickness has been carried out by visual determination of composition changes in cross section, determination of strength, density of the obtained concrete samples, and water content over cross section of concrete mix. According to the results of a visual study on composition of a concrete structure it has been revealed that 1/8 part of the structure (from an inner surface) does not have a large aggregate. Later, as it moves to periphery, there is an increase in coarse aggregate and a decrease in size and number of cells between grains of gravel. An analysis of experimental data has shown that properties of the centrifuged concrete in samples being sawn in layers change significantly: density of concrete in samples of an inner layer is lower by 8 % than in samples of an outer layer, and compressive strength of concrete – by 34 %, water content of concrete mixture of samples of the inner layer has turned out to be by 43 % higher than in samples of the outer layer. Approximating curves showing regularities of changes in density, concrete strength, water content of concrete mixture over thickness have been constructed in the paper. Linear and exponential equations have been obtained that describe changes in physical and mechanical properties of centrifuged concrete over section depending on structure properties as a whole, which, taking into account the obtained correction factors k1 and k2, can be used with an acceptable level of confidence in practical calculations of centrifuged concrete structures. Relationship between strength of centrifuged concrete varying over cross section and action of a centrifugal force of inertia has been revealed in the paper. An equation has been obtained that relates the strength of centrifuged concrete to its density. Analysis of the research results makes it possible to assert that the main source of loading perception in centrifuged concrete structures is outer layers.

The paper presents results of research aimed at developing a new semi-functional concrete additive that provides an increase in rate and level of its strength growth while reducing energy costs to accelerate hardening process, as a basis for reducing energy intensity in manufacturing of concrete and reinforced concrete products and structures. Experimentally a rational ratio of components for a polyfunctional additive has been found of mass cement: a superplasticizer based on polycarboxylate resins (for example, “Stachement 2000” or “Relamiks PC”) – 0.5 %, ultradispersed microsilica (SiO₂) – 1.0 %, sodium sulfate (Na₂SO₄), hardening accelerator – 0.5 %, aluminum sulfate (Al₂(SO₄)₃), sealing additive structure ‒ 0.25 %. The mentioned components ensure the largest increase in strength of cement stone and structural heavy concrete. Results of derivatographic and X-ray phase analyses have shown that strength growth is based on formation of a fine-crystalline form of low-base crystalline silicates of CSH-silicate group, which complements traditionally formed C₂SH by the reaction of threeand two-calcium silicate cement with water, as well as it is based on an increase in the number of neoplasms due to the reaction of Ca(OH)₂ with amorphous SiO₂ and ettringite 3CaO × Al₂O₃ × 3CaSO₄ × 32H₂O, being formed due to reactions with cement aluminates these are accelerating-compacting additive components, that in total provides an increase in density and strength of cement stone. While having the case with concrete, the effect is complemented by hardening the zone of contact between aggregate surface and cement stone due to the reaction between Ca(OH)₂ and SiO₂. These effects have been confirmed by growth (up to 38 %) of water which is chemically bound with cement in presence of a multifunctional additive in samples of cement stone, which is characterized by the largest strength. While using standardized testing methods, effectiveness of a multifunctional additive has been experimentally confirmed and it has been expressed in growth of quality characteristics and properties of structural heavy concrete: compressive strength – up to 40–60 %, flexural strength – up to 15 %, reduction of shrinkage – up to 50 % and water absorption – by 1.5–2 times, increase in frost resistance from brand F250 to F500, water resistance – from W6–W8 to W20.

The use of information technologies and, in particular, information training systems increases capacity of both a teacher and a student to achieve their goals in an educational process, taking into account individual characteristics of each and providing opportunities for continuing education. The paper proposes and considers a new automated learning management system, called CATS (Care About the Students). The proposed system covers all components of the educational process, allows to conduct an electronic journal of visiting and defending laboratory works, distribute topics and monitor progress of course and diploma projects (creating automatically task sheets with subsequent export to MS Word editor). The CATS LMS makes it possible to test students’ knowledge in control and self-education modes, to form electronic educational and methodical complexes, to inform students about topics of lecture and practical classes with the possibility of downloading relevant materials, to provide educational content in SCORM format, developed by teachers around the world. Working in the CATS system, it is possible to exchange messages with students and teachers, to monitor progress and process of studying in respect of the proposed material by students, to check accomplished assignments of students for plagiarism. The system under consideration also takes into account specificity of training at a technical higher education institution, providing for work with an integrated project management system and ability to submit bugs. The CATS LMS has been implemented as a web application using modern technologies and it is available in the local network within the whole university at [172.16.11.72:2020].

The task of controlling multi-link robots with manipulators for implementation of high-tech processes in industry has been considered in the paper. The paper presents sequential steps of using computer technology in construction of robotic-manipulators, including mathematical, algorithmic, and hardware and software tools for creating a multi-drive mechatronic system controlled by OMRON industrial microcontroller. A kinematic scheme of a robot manipulator has been described in the paper and it performs the following two types of movements – rotation around the z axis and rectilinear movement of a working element along a turning radius with precise positioning at a given point in the working space. Electromechanical design of the manipulator allows to ensure transportation of production objects in accordance with a given technological process. For designing the technological process of transporting production objects, a software module has been developed that makes it possible to automate description of basic operations for movement of the robot manipulator working body with subsequent automatic generation of a command sequence for a control program ensuring operation of electric drives in manipulator links in real time. To speed up the process of designing trajectory of the working body, a spatial simulation model of a robot-manipulator in the MatLab-Simulink environment has been developed. The paper considers a generalized diagram of a mechatronic control system for a robot-manipulator based on the OMRON programmable logic controller operating under control of a program developed in the programming environment Sysmac Studio Automation. A program for a programmable terminal with interface elements and animation elements has been developed for industrial use of the mechatronic system during adjustment and operation period. The paper provides an appearance of a robot-manipulator prototype. The developed mechatronic system of the robot-manipulator can be technologically oriented towards solving other problems of industrial production.