Vol. 4 Issue 4

Archives Journal Construction Materials and Products 2021

INFLUENCE OF MATERIAL STRUCTURE ON THE MAGNETOSTRICTIVE PROPERTIES OF A RADIATOR FOR DEFROSTING HEAT EXCHANGERS OF VENTILATION EQUIPMENT

https://doi.org/10.34031/2618-7183-2021-4-4-5-10
Abstract
The article deals with the properties of ferromagnetics and their behaviour in an external magnetic field. The conditions under which magnetism occurs in materials are shown and the choice of material for a magne-tostrictive emitter is justified. The composition and properties of permendur as the most suitable material for the manufacture of magnetostrictive radiators are presented. It is shown that for the manufacture of the magnetostrictor it is feasible to use electro-erosion equipment for cutting packages from permendur compared to the costly and cumbersome method of stamping in a matrix of a particular shape. Tests were carried out on a duralumin heat exchanger with artificial frostbite. The evaporator was fed with refrigerant at 0.22 MPa, which corresponds to the boiling point of R 410a refrigerant at 35°C, by means of a refrigerant line made of aluminium pipes. Frostbite was then produced by applying moist air using an ultrasonic steam generator. Frost on the evaporator surface is discharged by means of a magnetostrictor mounted on the heat exchanger. The proposed method allows for the most effective cleaning of the surfaces of heat exchangers of ventilation equipment from scale, fouling and other mechanical deposits by means of mechanical vibrations.
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INFORMATIZATION OF CONSTRUCTION MANAGEMENT AS A BASIS FOR PREVENTING MAN-MADE ACCIDENTS

https://doi.org/10.34031/2618-7183-2021-4-4-11-31
Abstract
The article presents the principles and algorithms of the finite element method in solving geotechnical problems taking into account seismic impacts for determining the stress-strain state of structures and slope stability, implemented in the Midas GTS NX software package. GTS NX allows you to perform calculations of various types of geotechnical problems and solve complex geotechnical problems in a single software environment. GTS NX covers the entire range of engineering and geotechnical projects, including calculations of the "base-structure" system, deep pits with various mounting options, tunnels of complex shape, consolidation and filtration calculations, as well as calculations for dynamic actions and stability calculations. At the same time, all types of calculations in GTS NX can be performed both in 2D and in 3D. The author does not claim to be the author of the finite element method, but he cannot do without pointing out the basic equations, as this affects the definition of the boundaries of use, the formulation of algorithms for constructing calculation schemes and the analysis of calculation results.
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ANALYSIS OF THE EFFECT OF METHODS OF INTRODUCTION OF ORGANOMINERAL ADDITIVES INTO MORTARS ON FINE SANDS

https://doi.org/10.34031/2618-7183-2021-4-4-32-40
Abstract
The use of technogenic raw materials in the production of building composites is an urgent direction in the technology of production of building materials in view of its economic efficiency, environmental effect and wide possibilities of their application. Recently, the issues of environmental safety in the production of building materials, the possibility of their processing and disposal have come to the fore. All this is dictated by the need for energy and resource conservation, the massive depletion of natural reserves and the progressive pollution of the environment due to anthropogenic activities. Construction composites provide ample opportunities for recycling of secondary raw materials, as their structure allows them to be used not only as a filler, but also in some cases as additives for regulating certain properties. More studied and widely used are ash and slag mixtures on the basis of which various organomineral additives are developed. So, on the territory of the Chechen Republic there are dumps of ash and slag mixtures, which, according to their chemical and mineralogical composition, are suitable for the design of organomineral additives and fillers in construction concretes and solutions. Building solutions are widely used for interior and exterior finishing works during the construction of construction projects in the Chechen Republic, which is characterized by high humidity in the winter, which provokes deformations of the plaster layer on facades. In this article, the development of an organomineral additive based on an ash-slag mixture is considered to improve the quality of mortar mixtures resistant to such conditions.
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EXPERIMENTAL STUDY OF PLATES FOR PUNCHING UNDER DYNAMIC LOADING

https://doi.org/10.34031/2618-7183-2021-4-4-41-48
Abstract
The issues of strength and deformability of reinforced concrete floors during punching remain insufficiently studied at present, despite the available publications in the technical literature. This article presents the results of experimental studies on punching of fragments of conjugation of flat reinforced concrete monolithic slabs with a column under dynamic loading. The purpose of these studies was to obtain experimental data on the stress-strain state of a fragment of a monolithic floor during dynamic punching with varying thickness and class of concrete, to reveal the failure patterns of experimental samples, and to obtain new experimental data. A setup for dynamic testing is described. Comparison of breaking load for specimens tested under dynamic loading with breaking load for specimens tested for static load is presented. The angles of inclination of the punching shear pyramid under static and dynamic loading are indicated.
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