Vol. 2 Issue 6

Archives Journal Construction Materials and Products 2019

TECHNOLOGICAL AND DESIGN FEATURES OF DESIGNING A MODULAR REINFORCED CONCRETE FOUNDATION FOR A HIGH-RISE BUILDING OF VARIOUS TYPES

https://doi.org/10.34031/2618-7183-2019-2-6-5-11
Abstract
The paper proposes a new type of modular collapsible reinforced concrete foundation for steel support for various types of structures: power lines, wind power plants, billboards, traffic lights, etc.The foundation has the shape of a cross-hammer in the plan and consists of separate modules manufactured at the factory and connected to each other by concrete dowels and tie bolts on the construction site. At the same time, this technological approach makes it possible to obtain more stable (uniform) strength and deformation properties of both the individual module and the assembled foundation as a whole. Reducing the material consumption is achieved by creating a cavity in each typical module and filling it with local inert material (soil). The central module has an anchor device for joining with the support according to the type of flange connection. This device, along with the use of conventional anchor bolts, involves filling the central module with non-shrinkable fast-hardening steel-fiber concrete. Thus, the positive result of the proposed solution is to increase the bearing capacity of the foundation as a whole, increase the strength and stiffness of its main joints, and simplify installation in comparison with traditional approaches to construction. A comparative calculation of the foundations of the proposed and standard known solutions showed the effectiveness of the first one by at least 17.2%.
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ANALYSIS OF THE RESULTS OF MONITORING OF DYNAMIC IMPACTS DURING EXPERIMENTAL IMMERSION OF DRIVING PILES AT THE CONSTRUCTION SITE OF THE CAMPUS OF SFU

https://doi.org/10.34031/2618-7183-2019-2-6-12-19
Abstract
In the framework of the work the values of the vibrodynamic loads when driving of the two piles and their impact on the existing slab on pile foundation of dormitory № 8b and at the gas station in the 25-meter zone from the place of piling were determined. Calculations of the actual impact of the immersion of piles in the residential area of the campus of SFU (dormitory No. 8b) on the existing slab were made, the results of which revealed that the impact on the existing building does not exceed the maximum permissible value. At the same time, calculations were carried out on the existing gas station, the results of which showed that at a distance of 15.0 m, the clogging will not cause the development of deformations of the bases of existing structures of any type, based on soils from soft-plastic to hard consistency.
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EFFECT OF MICROFILLERS BASED ON NATURAL WOLLASTONITE ON PROPERTIES OF FINE-GRAINED CONCRETE

https://doi.org/10.34031/2618-7183-2019-2-6-20-28
Abstract
The possibility of obtaining effective highly dispersed additives from natural wollastonite is substantiated and their influence on the properties of fine-grained concrete is investigated. On the basis of wollastonite, a complex micro-filler with particle sizes up to 100 microns was developed, obtained by joint grinding with quartz sand in a 3:1 ratio in a ball mill in the presence of an anionic surfactant naphthalene-formaldehyde type C-3 and a calcium stearate hydrophobizer technical C-17. A suspension of wollastonite with a modal particle diameter of 405 nm was obtained by pre-grinding wollastonite and anionic surfactant in a ball mill, with their further ultrasonic treatment in a bath-type activator. Mathematical models of the dependence of compression and bending strength on the content of the initial components are developed. It is established that the complex microfill leads to an increase in the strength of fine-grained concrete in bending by 2 times, in compression by 1.7 times with its content in the composition of fine-grained concrete in the amount of 10% by weight of cement. Wollastonite suspension increases the bending strength of fine-grained concrete to 3.1 MPa, compression to 57.8 MPa. The results of qualitative x-ray phase analysis showed that the total intensity of diffraction maxima of not fully hydrated alite C3S, belite C2S grains and their aggregates in cement stone with wollastonite decreases by 1.5-2 times compared to the control composition. This is most likely due to the amorphous nature of the wollastonite surface after grinding in a ball mill and ultrasonic dispersion in a bath-type activator. In addition, such particles are the centers of crystallization. Their needle-like shape contributes to the reinforcement of the structure by crystallizing new formations of cement stone.
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STRESS-STRAIN STATE OF THE SYSTEM “COMBINED TOWER-REINFORCED CONCRETE FOUNDATION-FOUNDATION SOIL” OF HIGH-RISE STRUCTURES

https://doi.org/10.34031/2618-7183-2019-2-6-29-37
Abstract
The aim of the work was to evaluate the effectiveness of the system "combined tower-reinforced concrete foundation-foundation soil" for high-rise structures on the example of a wind power plant (wind turbine) with a capacity of 1.5-2.0 MW using computer modeling in the PC "Ansys". Thus, under the combined tower the article refers to high-rise building, consisting of two parts: the lower composite, the upper – in the form of a thin-walled core-shell closed profile. In both cases, the shell is a pipe with a weak taper. As an analogue, the WPP considered in foreign literature is adopted: the radius of the rotor is R=41 m, the height to the axis of the wind wheel is zhub=80 m. The shell is made of high-strength C355 steel and, unlike the analog in this work, the cavity of the lower part of the tower to a height of 20 m was filled with B60 class concrete. The modeling took into account the spatial work of the elements of the structural system and the physical nonlinearity of the materials from which they are made. At the same time, the Mises strength theory was used for steel, the Williams – Varnake theory for concrete, and the Drukker – Prager theory for the foundation soil. Comparison of the calculation results with the analog showed that the destructive load of the tower increased by 37% due to filling the lower part of it with concrete, which indicates the effectiveness of the proposed solution. In this case, the destruction of the tower with a concrete core and without it occurred from the loss of local stability of the steel shell at the level of the junction of the tower with the foundation (with a compressed zone).
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ACTUAL PROBLEMS OF URBAN LAND USE ON THE EXAMPLE OF KRASNOYARSK

https://doi.org/10.34031/2618-7183-2019-2-6-38-43
Abstract
In the modern world, in using land resources, we are faced with a number of problems, this is more expressed in megacities, because the majority of the population of our planet lives in these territories.
The article briefly analyzes the current state of Krasnoyarsk, physical-geographical and economic conditions of the city development. The issues of territorial planning in the city are considered on the example of the microdistrict "Pokrovsky". High-rise buildings and their crowding influenced on the formation of wind flows and dispersion of impurities. It is established that the building affects the wind speed, reducing it by nearly 25-30% compared to the undeveloped urban part. In a dense building, the wind speed can be reduced to 70%. Inefficient land use model is reflected in the quality of the living environment, including the connectivity of the territory. The infrastructure is developed for children of younger preschool age-yard areas are everywhere equipped with children's game elements. Social adaptability for the elderly in the district is poorly expressed. The issue of parking spaces is acute, and their lack indicates the impossibility of creating a neighborhood with a high level of quality of life. Local prob-lems include the construction of noise screens along major highways, which have a low-quality design and technical solution. The provision of public transport is unsatisfactory. Spatially in the "intercession" we need a clear separation of yards and public spaces. Due to this, within the four large neighborhoods-quarters there will be a quasi-quarterly structure that helps to organize the hierarchy of spaces, eliminating or minimizing transit traffic through the yards.
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TRANSITION FROM INFORMAL TO SUSTAINABLE SETTLEMENT

https://doi.org/10.34031/2618-7183-2019-2-6-44-49
Abstract
The article is devoted to the features of informal settlement in Addis Ababa and the role of governmental and non-governmental organizations and public participation in the sustainable development of informal settlements. The purpose of the article is to identify the main types and characteristics of informal settlements and to reveal the factors that hinder the success of programs for updating informal settlements in the city. The research methods were the analysis and generalization of domestic and foreign literature on this research problem. The main conclusion of this study is that the principles of folk architecture are integral components of solutions for the sustainable development of informal settlements.
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ARCHITECTURE PLANNING AND DESIGN CONCEPTS OF PRIMARY HEALTH CARE INSTITUTIONS IN YEMEN

https://doi.org/10.34031/2618-7183-2019-2-6-50-57
Abstract
This article discusses the main aspects of the location of primary health care facilities in Yemen. We studied the requirements directly for the site of such medical care institutions. It is also revealed how to determine the correct orientation of the building center. In addition, the functional components and construction sites of primary care facilities are described. The components of a medical center include: the first floor – a medical center, the second floor - a doctor's apartment, a security room, an electric generator, an incinerator for medical waste, and a fence for a medical center. The article defines the architectural principles and elements of the project of medical centers. These elements of the project of primary health care institutions include: the main entrance, administrative department, medical services section, examination rooms, rest rooms, radiology room, surgical ward, pharmacy, mechanics section. The general design assumptions for the building of primary health care are discussed. Design standards for these institutions are identified.
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