Bulletin of Prydniprovs'ka State Academy of Civil Engeneering and Architecture

10-19

Authors: V. I. Bolshakov, O. B. Zahorodniy, S. I. Veselova

Goal. To investigate the phase composition of the obtained sealing coatings based on aluminophosphate compound (APC) and the impact of temperature rise on it. Methods. Qualitative X-ray phase analysis (XRPA) and differential thermal analysis (DTA) are used as the methods of research. Roentgenograms for structural analysis were obtained on a DRON-4-07 using filtered copper radiation in the secondary beam. Registration and initial processing of diffraction patterns was performed using the software package PDOS with the output of the diffraction patterns on the screen. Using the "loupe" option allowed to identify weak interference lines, which increased the accuracy of the method of qualitative XRPA. The thermograms for DTA received on the device type Termoskan-2. The results. It is revealed that base of coating is X-ray amorphous phase. There are following crystalline phases: Al, AlPO4, Al (PO3) 3, BN found in the coating. It is revealed that annealing doesn’t make a significant influence on the phase composition of the crystalline phases and the coating doesn’t lose properties after annealing during repeated thermal stress. Scientific novelty. The phase composition of the proposed sealing coatings based on APC and produced by plasma spraying, and the effect of annealing on the phase composition of the coating are investigated. The reaction of synthesis of primary material forming on the basis of APC for coating is offered. Practical significance. The results can be used in aviation technology in the development of gas turbine engines (GTE) and the design of the compressors. The sealing coating may be used to improve the reliability of the compressor and to increase the efficiency ratio of turbine engine. During the operation the compressor’s blades touch the sealing coating of compressor’s stator and grooves it without causing locking and destruction of the rotor. Therefore, the development of new sealing coating compositions that provide reliable operation of the GTE compressor, and determination of their properties and structure, are very important.

35-48

Authors: V. I. Bolshakov, A. N. Motornyi

Reasons analysis of the «topolina» catastrophe occurrence and activities, excluding similar phenomena in designing and construction of buildings and structures on collapsible soils (to the 20th anniversary of disaster management). General prerequisites for the causes forming of “topolina” catastrophe (part 2) It is presented historical information about the formation of the Dnepropetrovsk city council a new neighborhood – «Topol». The analysis of survey materials for the construction of new residential community «Topol-1», «Topol-2», «Topol-3» was made. Geotechnical and hydrogeological conditions of the area for construction of housing estate «Topol-1» were analyzed. The justification of the offered variants of the residential houses foundations under construction, social and cultural objects, submitted by project organization SPI «Ukrspetsstroyproekt» are given. We analyzed the design decisions UMZ residential complex foundations along the Zaporozhskoe shosse street. It was disclosed forced replacement of the proposed variant of pile foundation under the projected SPI «Giprograd», housing estate on another version of foundations on the artificial basis after the transfer of the construction site from the second type to the first type of ground conditions by subsidence. It is given a brief justification of the flooding onset of the already exploited residential construction during the preliminary soaking of the territory for the residential complex UMZ. It is also revealed the reason for the occurrence of supranational deformations of the basements, foundations and structures of the lightest buildings of pre-school children's institutions, which are in operation before the preliminary soaking of the UMZ residential complex territory. The suffosion processes occurrence on the territory of the Topol-1 residential area, connected with the unloading occurrence of groundwater and increasing of the pressure gradient, decompaction and weakening of the soils of the second slope of the «Vstrechnaya» beam is substantiated. The cause of the hydraulic breakthrough of the destroyed second slope of the «Vstrechnaya» beam and the consequences that follow from this was disclosed. It is shown errors in purpose of SE «DneproNIISP» taking into production version of pre-soaking the upper area preparing for the construction of residential complex UMZ. The material and moral damage of the occurred catastrophe of a housing estate «Topol-1» and the existing material and moral losses on the Dnieper railway are presented. It is presented the general conclusions of the expert committee and a separate opinion of the expert committee member, the author of this article N. A. Motornyi.

55-61

Authors: I. F. Tkachenko, M. A. Uniyat

Problev. Performance, eliminating the anisotropy of the mechanical and physico-chemical properties by optimizing the chemical composition of the steel E36 in the normalized condition. Methodology. Study of the multi-objective optimization influence of steel E36 chemical composition on the mechanical characteristics were carried out with the use of computer methods Roshal deep data analysis abbreviated GRAD. Findings. There was solved the actual scientific and technical problem of improved performance, elimination of anisotropy of the mechanical and physico-chemical properties by the chemical composition optimizing in the work. Originality. Using the methods of deep exploratory data analysis, it was investigated the effect of production parameters on the mechanical properties. It was observed the influence of heat treatment on the distribution of chemical elements, the microstructure, hardness and mechanical properties of low alloy steels. Practical value. Using the methods of mathematical analysis, it was made optimization of the chemical composition of the steel E36.

78-84

Authors: Yu. M. Yarovoj, O. Ye. Lukashenko, E. O. Perepelica

Formulation of the problem. Nowadays there are more than 3000 masonry chimneys in Ukraine. The life of most chimneys is more then 20 years, about 20 % of the chimneys are operated for more than 50 years. Inspection of the technical condition of the chimneys, evaluation of their load-carrying capacity and design of recommendations for further work of chimneys is an actual research task. There are no actual normative documents about calculation and design of masonry and reinforced concrete chimneys in Ukraine. In reference literature and normative documents, the design scheme of the chimney trunk is adopted in the form of a cantilever beam. In the calculation it is recommended to take into account the longitudinal-transverse bending from the action of the wind load and its own weight, as well as the roll of the foundation. Strength test of the trunk is performed separately for horizontal sections and for vertical sections. For horizontal sections it is performed for longitudinal force and bending moment from its own weight and wind load, for vertical sections – for temperature forces after the temperature drop along the thickness of the barrel wall. This approach doesn't fully reflect the real work of the masonry, which is in a complicated state of stress. Purpose. To perform a comparative calculation of the various trunks of masonry chimney, analyze the factors affecting the stress-strain state of the masonry trunks. Conclusions. It is proposed carry and calculation of the masonry trunks for the temperature impact in elastic stage with regard to join work masonry and clamping rings, taking into account not only the tangential, but also the longitudinal temperature stresses and analyze the work of the masonry in the plane stress state. Proposed calculation makes it possible to determine the moment of formation of force and temperature cracks in the masonry. It is necessary to clarify the stress-strain state and criteria of the trunks strength of masonry chimney under a two-dimensional stress state with the help of numerical and experimental models.

93-100

Authors: N. V. Kondrateva, L. V. Moroz, V. Yu. Moroz, A. I. Begun

Statement of the problem. A disadvantage of the gypsum binder is the limited water resistance of products that historically led to the use of gypsum products mostly for internal construction and finishing works. To regulate the process of hydration and structure formation of the use of chemical additives that are introduced with the mixing water or in the production of the binder. As a rule, substances that increase the solubility of the gypsum binder referred to as the hardening accelerator, and substances which retard the solubility of the inhibitors of hardening of the mixture. Most accelerators and retarders hardening affect adversely on the final strength of the mixture. More effective impact on gypsum binder additives have plasticizers. The purpose of the article. Getting gypsum binder modified with the aim of improving its water resistance and improvement of some technological factors (the time of hardening, water gypsum ratio, etc.) would reduce its shortcomings and expand the scope of application of the binder. Conclusion. The result of the research reviewed changes in the basic properties of the gypsum binder with the introduction of additives, plasticizers, and selected the most effective supplements to significantly reduce water gypsum ratio, to improve strength properties and to obtain gypsum binder more dense structure.

108-113

Authors: O. O. Lesyk-Bondaruk

This article is dedicated to Lutsk monasteries building system and its role in city housing system formation. Lutsk is one of the oldest cities of Ukraine, it has ancient and famous history, which is tightly connected with various religious confessions history. Monasteries always played an important and often even dominant role in city housing system. Lutsk monasteries analysis allowed to find out that all of them are united by typical city location principles. The author outlines peculiarities of monasteries location depending on their initial function, a number of city construction peculiarities of actual monastery complexes; investigates current monasteries system preservation and reconstruction according to historical and architectural context of existing building system, modern needs and city architecture development tendencies.

120-126

Authors: I. O. Merylova

Formulation of the problem. Abstract. Formulation of the problem. The solution of urban development problems of an extensive and accessible network of out-of-school educational institutions, the formation of proposals for the placement of out-of-school institutions in the structure of the building and functional and planning features of the organization of territories of out-of-school institutions has systemically character. The system approach involves studying not only the internal functional structure of the territory, buildings and structures, but also the analysis of the connections of out-of-school institutions with all urban buildings, with industrial enterprises and research organizations, with a network of public service institutions and with other educational establishments. Article purpose: to analyze theoretical research in the field of urban planning, which should be taken into account when developing principles and methods for optimizing the network of out-of-school educational institutions. Conclusions. The research found that the systematic approach implies relation of out-of-school educational institutions with all urban environment, as well as with industrial enterprises and research organizations, with a network of public service institutions and, most importantly, with other educational establishments. The formation of a network of out-of-school educational institutions directly depends on the tendency of the development of social-pedagogical programs and the reform of the educational sector as a whole. The main system properties of a network of out-of-school educational institutions were determined. It was found that the cooperation of the resources of out-of-school and general education institutions is one of the effective ways to develop continuing education. In the state programs of educational reform is noted that the cooperation of the resources between the out-of-school institutions and general educational schools are one of the effective ways of developing continuing education. These provisions to provide an opportunity to significantly expand the network of out-of-school institutions and the creation of new types of out-of-school institutions in the structure of territorial educational districts.