Design Features of Three-Layer Slab Reinforced Concrete Structures

2018 ◽  
Vol 931 ◽  
pp. 264-268
Author(s):  
Alexey V. Belyaev ◽  
G.V. Nesvetaev ◽  
Dmitry R. Mailyan

The creation of the efficient reinforced concrete structures, that allows to reduce the material consumption as well as the labor costs, is the most important task today. One of the possible ways of solving this problem is the design and wide application of multilayer structures in which high mechanical, heat engineering and acoustic properties are provided due to the combination of high strength of heavy concrete and low strength of light concrete with low heat conductivity. The advantages of three-layer reinforced concrete structures are shown. The proposals have been made to take into account the sag and the classes of lightweight concrete of such elements.

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Alexander Bulkov ◽  
Michail Baev ◽  
Igor Ovchinnikov

The influence of reinforcing steel corrosion on the durability of reinforced concrete structures of transport structures and the degree of knowledge of this problem is considered. It is specified that the protection of reinforcing steel from corrosion is not able to completely replace the correct design and use of high-strength concrete. But it is able to extend the life of reinforced concrete structures. It is noted that corrosion of the reinforcement leads to a decrease in the structural strength due to wear and tear and by a third of the period of operation of reinforced concrete structures, as a result of which transport structures collapse. As an example of the detrimental effect of corrosion of reinforcing steel on the durability of transport structures, examples of accidents of bridges and overpasses caused by this type of corrosion are given. As a result, a conclusion is drawn on the advisability of ensuring a sufficient level of corrosion protection of reinforcing steel to achieve the required durability of reinforced concrete structures of transport structures. The types and causes of corrosion processes in reinforcing steel reinforced concrete structures are described. The compositions and technologies of anticorrosive protection are examined and analyzed. Comparison of the compositions of anticorrosive protection of reinforced concrete structures is carried out according to the following criteria: consumption, density, viability, curing temperature and the number of components of the composition. A comparison of anti-corrosion protection technologies is carried out on the basis of the following indicators: line dimensions, productivity and consumption of energy resources. A comparison is also made of the cost of using various anti-corrosion protection technologies. Based on the data obtained, the advantages and disadvantages of the considered compositions and technologies of corrosion protection are determined. As a result, the most effective and technologically advanced method of corrosion protection of steel reinforcement of reinforced concrete structures of transport structures is selected.


2018 ◽  
Vol 7 (3.2) ◽  
pp. 370 ◽  
Author(s):  
Oleksandr Semko ◽  
Viktor Dariienko ◽  
Vitaliy Sirobaba

The calculation, modeling and experimental research of steel-concrete tubular elements made of thin-walled galvanized sheet metal and lightweight concrete have been carried out. The proposed type of structures can be used as a separate structure in the form of a column or a pillar, and one of the types of the reinforcement of a certain light structure. The basic technological and constructive requirements for manufacturing and further exploitation of structures are given. For determination of actual work’s indexes of constructions experimental research of standards are undertaken, and recommendations on adjustment of well-known calculation formulas of close constructions as for structural parameters are given. The design (modeling) was performed in MSC / Nastran software. An analysis of the proposed structures use is carried out with the corresponding conclusions. 


2020 ◽  
Vol 10 (10) ◽  
pp. 3570
Author(s):  
Romualdas Kliukas ◽  
Ona Lukoševičienė ◽  
Arūnas Jaras ◽  
Bronius Jonaitis

This article explores the influence of transverse reinforcement (spiral) and high-strength longitudinal reinforcements on the physical-mechanical properties of centrifuged annular cross-section elements of concrete. The test results of almost 200 reinforced, and over 100 control elements are summarizing in this article. The longitudinal reinforcement ratio of samples produced in the laboratory and factory varied from 1.0% to 6.0%; the transverse reinforcement ratio varied from 0.25% to 1.25%; the pitch of spirals varied from 100 mm to 40 mm and the concrete strength varied from 25 MPa to 60 MPa. Experimental relationships of coefficients for concrete strength, moduli of elasticity and limits of the longitudinal strain of centrifuged concrete in reinforced concrete structures in short-term concentrically compression were proposed.


2019 ◽  
Vol 135 ◽  
pp. 02022
Author(s):  
Tamara Danchenko ◽  
Anatoly Lastovka ◽  
Sergey Amelchugov ◽  
Nadezhda Klinduh ◽  
Maria Berseneva

Abstract in the article the main types of building structures are considered, which are distinguished by the type of material. For the purpose of studying, each type has brief information including its advantages and disadvantages in comparison with others. In the section reinforced concrete structures, the authors characterize this material from three sides - this is the method of manufacture, the type of concrete and its stressed state. As a result, it was found that when choosing a foundation, special attention is paid to: bearing capacity, type of building being built, soil characteristics. In addition to the above, it can be added that weight reduction, cost reduction and material consumption in reinforced concrete structures are possible through the use of high-strength concrete and reinforcement. Metal structures are the most popular building material. The possibilities of this material are very diverse: building designs, designs specifically for certain seismic and climatic conditions, and high decorative properties. Due to its strength and rigidity, buildings can withstand hurricane gusts of wind and earthquakes. In the manufacture of structures in the factory and during installation, steel is subjected to various technological operations: welding, cutting, machining. It was found that in this case the steel does not collapse, it retains the microstructure and mechanical properties. Finally, steel should not have a significant cost of manufacturing structures from it. Turning to the section of wooden structures, the authors list the main advantages - it is comfortable and environmentally friendly and material.


2020 ◽  
Vol 9 (1) ◽  
pp. 2219-2225

The technology of manufacturing reinforced concrete structures of long-line systems of formwork-free shaping is widely used lately in construction industry in many countries. Using this technology, industrial construction can be carried out in accordance with the requirements of modern regulatory documents that allow projects to be developed individually, and production can be reoriented in a very short time in accordance with emerging needs. This means that on the same production line it is possible to produce various structural elements of buildings and structures. Also, this technology allows the production of structures according to a wide range of products that meet operational requirements, and increases the possibility of their use in design of buildings and structures with various architectural, planning and structural decisions. Prestressed hollow-core slabs of formwork-free shaping reinforced with high-strength wire reinforcement are widely used due to the simplicity of construction and their relatively low cost, as well as their high bearing capacity, large spans and better quality. The problem of their introduction into construction industry of Uzbekistan is that the issues of designing, manufacturing and using them in construction have not been studied. Besides, the production technology of such slabs is mostly associated with the construction in non-seismic areas, and the country does not have an appropriate regulatory framework for the possibility of slab designing and production. The aim of the study is to assess the strength and serviceability of hollow-core slabs of formwork-free shaping, designed on the basis of the proposed structural solution of the slab cross section and intended for construction in seismic areas. Therefor the issues of optimizing the main reinforcement consumption (prestressed high-strength wire reinforcement) at class B30 concrete strength without using the non-stressed reinforcement (reinforcing products) for the product range under consideration were addressed. Theoretical and constructive solutions of the slabs were developed in accordance with the standard requirements of Uzbekistan KMK 2.03.01-96 “Concrete and reinforced concrete structures”, KMK 2.01.03 “Construction in seismic areas” and considering the Euronorm EN 1168-2005 requirements “Precast concrete. Hollow-core slabs”.


Sign in / Sign up

Export Citation Format

Share Document