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Vol. 2 Issue 2

Archives Journal Construction Materials and Products 2019

IMPROVING THE EFFICIENCY OF FIBRE CONCRETE PRODUCTION

https://doi.org/10.34031/2618-7183-2019-2-2-4-9
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 4-9 p.
Abstract
Fiber concrete is one of the types of effective building materials that ensure the operational reliability of structures due to a set of unique properties. However, the maximum physicomechanical characteristics of this type of products are achieved only if the fiber is evenly distributed in the concrete matrix and the optimum ratio of raw materials is reached. In this connection, the aim of the work was to increase the production efficiency of fiber-reinforced concrete by optimizing the formulation and technological parameters of its manufacture. The optimal method of introducing the fiber into the concrete mix and the type of superplasticizer were previously determined, which allowed ensuring the maximum physicomechanical characteristics of the products. Optimization of prescription parameters was carried out using the method of mathematical planning of the experiment, where the amount of cement, superplasticizer and basalt fiber were varied. After processing the results, the dependences of the compressive strength on variable factors were obtained, which would allow to select the optimal dosages of raw materials for given mechanical characteristics of the products.
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COMPOSITE BINDING MINERAL ADDITIVE INFLUENCE ON THE PLASTICIZER EFFICIENCY

https://doi.org/10.34031/2618-7183-2019-2-2-10-16
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 10-16 p.
Abstract
Replacing portland cement with composite binders in many construction spheres is becoming increasingly reasonable. A prerequisite for this is the ability to provide the binder with set of properties necessary for the most effective implementation of a particular practical task at minimum expense. Such optimization allows in some cases to achieve higher performance than the original cement, in others – to form new properties of the material, as well as provide direct or indirect savings of various resources. One of the most important parameters determining the strength characteristics of composites and their durability is the used binder water requirement. Furthermore in some cases the mixture must have certain rheological characteristics. Various types and generations plasticizing and water reducing additives are widely used to regulate these parameters. The article discusses relation of fine components electrosurface properties – the clinker component and various genetic types mineral additives for the main types of plasticizers magnitude diluting effect. The basic mechanisms and regularities are described, recommendations that allow to optimize the consumption of expensive additives or increasing their effectiveness in solving various practical problems are formulated.
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ANALYSIS OF THE CAUSES OF ACCIDENTS AT DIFFERENT STAGES OF LIFE CYCLE OF THE CONSTRUCTION OBJECT

https://doi.org/10.34031/2618-7183-2019-2-2-17-22
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 17-22 p.
Abstract
The article deals with the main causes of accidents of buildings and structures that occurred due to errors made at different stages of their life cycle (design, construction, operation). A brief analysis of the accidents that occurred from 2010 to 2017 in the Russian Federation is presented. The study of the causes of accidents makes it possible to understand better the laws of structures, buildings and structures, to identify errors that lead to emergencies. Such errors include: low quality of construction and installation works, deviation from the project in the construction of buildings and structures, the use of materials of inadequate quality, overload of load-bearing structures during operation. Also, the causes of accidents include defective engineering-geological and hydrogeological studies of the grounds. Analysis of accidents showed that the last few years there is no tendency to reduce the number of accidents of buildings and structures, which indicates an insufficient number of measures to prevent them. In the article the authors consider the examples of accidents in construction, which occurred due to the main reasons, and ways to prevent accidents in the future.
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THE ALGORITHM OF COMPLEX DIAGNOSTICS OF TECHNICAL CONDITION OF BUILDING STRUCTURES ON THERMOGRAMS ANALYSIS

https://doi.org/10.34031/2618-7183-2019-2-2-23-28
 23-28 p.
Abstract
The algorithm of complex diagnostics of a technical condition of building constructions and structures on the analysis of thermograms is offered. An attempt is made to systematize and logically build a sequence of stages of energy inspection of heat-consuming and heat-generating construction projects and their structural elements. The presented algorithm includes the main stages performed in such surveys. It differs from the known technologies of energy monitoring of buildings and structures by the presence of two additional stages, which are an integral part of any energy survey: determination of the relative surface humidity of building structures and the actual mass flow of coolant through the heating device for the analysis of thermal images. The implementation of energy (thermal imaging) and technical inspections according to the presented structural scheme requires not only the presence of appropriate instrumentation and measurement base, but also the involvement of highly qualified specialists (civil engineers, thermal power engineers, thermal physicists, operators-thermographers, etc.).
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CALCULATION OF THE SLEEVE PACKER ELEMENT WITH THE VARIABLE ANGLE OF LAYING OF THREADS OF THE CORD FOR CREATION OF EDGE PROTECTION (PART 1)

https://doi.org/10.34031/2618-7183-2019-2-2-29-40
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 29-40 p.
Abstract
The method of calculation of influence of design and technological parameters of material of a cover of a packer element is developed: the initial angle of laying of threads of the reinforcing framework, the packing density of threads in the field of unions, number of layers of a framework, rubber elastic modulus on power characteristics of a cover, for the purpose of creation of edge protection of a packer element. In the first part of work the cover of a packer element with laying of threads with a constant corner on all length of a cover is investigated. The received results of calculation, allowed to evaluate and prove quantitatively the constructive and technological directions of reliability augmentation of edge protection of a packer element. The developed calculation procedure is a basis of development of more general method of calculation of power characteristics of a cover of a packer element with variable longwise covers the initial angle of laying of threads.
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CALCULATION OF THE SLEEVE PACKER ELEMENT WITH THE VARIABLE ANGLE OF LAYING OF THREADS OF THE CORD FOR CREATION OF EDGE PROTECTION (PART 2)

https://doi.org/10.34031/2618-7183-2019-2-2-41-49
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 41-49 p.
Abstract
In the presented part of work the case with the angle of laying variable longwise of the reinforcing threads of a packer element in median and edge zones is investigated. Calculation of power characteristics of a cover of a packer element with various slopes is carried out. Tests of natural prototypes of covers the packer ele-ments are carried out. The calculation results compared with data of an experiment are presented in the form of schedules with good degree of convergence. The developed technique allows to choose an optimum design of covers of a packer element with higher value of rigidity on face sites that ensures reliable functioning of a packer element at pressure differences in annular space.
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