the article deals with the issues of anchoring external composite reinforcement. The advantages of one of the reinforcement options are described - with the help of anchor harnesses. The procedure for performing work when reinforcing with anchor harnesses is presented. Also presented is a method for calculating pull-out anchors made of carbon fibers.

Keywords: reinforced concrete, concrete, composite materials, carbon fiber, reinforcement, external reinforcement, composite anchor

А comparative analysis of individual indicators of the classical and new methods of strengthening reinforced concrete structures is given, a possible option for increasing the level of efficiency of external composite reinforcement is shown. The elements of the research program are presented, with a description of the materials and the main characteristics of the samples.

Keywords: reinforced concrete, concrete, rebar, composite materials, carbon fiber reinforced plastic, reinforcement, external reinforcement, experiment

The article discusses possible design solutions to improve the seismic resistance of stone buildings. In particular, the installation of antiseismic belts at the floor level, the installation of dowels and nodes for connecting the floor slabs with the walls and among themselves, the reinforcement of the walls with steel clips, as well as the installation of transverse frames, if the maximum distances between the axes of the transverse walls are not observed.

Keywords: stone buildings, seismic resistance enhancement, reconstruction, design solutions

The analysis of the results of large-scale experimental studies carried out at the Department of Reinforced Concrete and Stone Structures of DSTU is presented. It is aimed at determining the possibility of effective implementation of new composite materials in construction. This article deals with the issues of strength and stiffness of bending reinforced concrete elements with internal working reinforcement made of composite materials, or reinforced with external glass and carbon fiber reinforcement. The possibility of using coal and fiberglass working reinforcement for conventional bending elements in which the value of the maximum permissible deflections is not decisive has been established. The high efficiency of external reinforcement when reinforcing reinforced concrete structures with composite materials has also been proven.

Keywords: concrete, reinforced concrete, composite materials, reinforcement, concrete, strength, deformability

The article discusses the most common types of modified columns in Mexico: composite section columns, high-strength concrete columns, prestressed concrete columns. The procedure for calculating columns and new proposals to improve construction efficiency is described. Columns are one of the most important elements of orthogonal frame buildings, so improving their designs requires special attention. In composite section columns, using high-strength concrete in the outer zone, the strength of the concrete located in the core increases 1.5 times more, which significantly increases the efficiency of the structure. Columns made of high-strength concrete have an increase in efficiency when used in high-rise buildings. Prestressed concrete columns are very effective because they have high resistance to load, they are able to withstand significant stresses.

Keywords: concrete, reinforcement, reinforced concrete, high-strength concrete, prestressing, columns, columns of composite section, eccentricity, stress, deformation

The search for the most efficient and cost-effective materials and structures is an important and urgent task. Reducing steel consumption can significantly affect the cost of structures, and the use of high-strength steel is one such method. Currently, there is great interest in reinforced concrete structures, which contain various combinations of pre-compressed, pre-tensioned and non-tensioned reinforcement. To determine the dependence of the bearing capacity on the class of concrete using the example of flexible reinforced concrete columns with combined reinforcement, a numerical experiment was performed. The performed numerical experiment showed the feasibility of using combined reinforcement - all the racks considered in the experiment with combined reinforcement are more effective than racks with non-tensioned reinforcement. At the same time, depending on the relative eccentricity of external forces and flexibility, it is necessary to choose the most effective type of combined reinforcement.

Keywords: column, combined reinforcement, prestressing, flexibility, reinforced concrete

The effective use of high-strength reinforcement in reinforced concrete structures is an important task today. In order to reduce the consumption of materials, especially steel, it is necessary to use high-strength materials more widely in the production of reinforced concrete structures. In recent years, researchers have significantly increased interest in reinforced concrete structures with mixed reinforcement. To determine the effect of the concrete class on the bearing capacity of reinforced concrete columns, a numerical experiment was performed. According to the results of the experiment, it was found that the maximum increase in bearing capacity with all variants of relative eccentricity is observed in racks with previously stretched and non-tensile reinforcement. Thus, the studies showed that the use of columns with mixed reinforcement is advisable. The use of mixed reinforcement in reinforced concrete racks in all cases is more effective than racks with non-tensile reinforcement.

Keywords: concrete, reinforcement, reinforced concrete, prestressing, the relative eccentricity, mixed reinforcement, column, bearing capacity

In the view of most people, the criterion "high-rise buildings" is very blurred. Five or seven storey buildings were considered one or two centuries ago to be tall, but now you will not surprise anyone with a number of storeys over fifty. Russian law sets the maximum possible 75-meter height for residential buildings and 50-meter - for public buildings. The construction of higher facilities is subject to special requirements. The article discusses the development of high-rise buildings of a megalopolis using the example of the city of Rostov-on-Don, presenting famous high-rise buildings in Rostov at present. Along with increasing the number of storeys of buildings, their design features are also changing. The types of structural schemes of high-rise buildings, the materials of the supporting structures of high-rise buildings, their advantages and applications are described. The problems that arise in high-rise construction are described.

Keywords: Rostov-on-Don city, high-rise construction, number of storeys, development, urban planning, zoning, architecture, design, high-strength concrete, high-strength reinforcement

Effective use of high-strength reinforcement in concrete structures - an important task today. Studies of Russian and foreign scientists have shown that the most expedient are combination of prestressed and untensioned reinforcement in section. When designing the compressed concrete elements with prestressed reinforcement should strive to reduce the amount of pre-tension reinforcement in columns, on the contrary, to increase the pre-compressed in short elements. In elements with pre-compressed steel, untensioned reinforcement is needed, because it provides improving crack resistance during transmission technology process tensile stresses on the concrete and untensioned reinforcement. The percentage of this reinforcement should be the minimum necessary to achieve the required cracking resistance. Minimal amount of pre-tension reinforcement adopted at the level of prestressing (usually the highest) should be taken of the conditions provide the desired crack resistance and rigidness. Later in the article describes main principles the calculation minimum number of prestressed reinforcement in reinforced concrete elements to the presentation requirements of the first, second and third categories crack resistance.

Keywords: concrete, reinforcement, steel, reinforced concrete, prestressing, crack resistance, rigidity, bearing capacity, deformation