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Keywords: reinforcement

PROGRAM OF EXPERIMENTAL STUDIES OF THE LOAD-BEARING CAPACITY OF GIRDERLESS PLATES FOR PUSHING UNDER DYNAMIC LOADING. DESIGN OF PROTOTYPES

https://doi.org/10.34031/2618-7183-2020-3-3-47-53
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 47-53 p.
Abstract
This article presents a program for experimental research of the behavior of reinforced concrete slabs when forced through in static and short-term dynamic loading modes. At hazardous production facilities, there is always an increased probability of emergency situations of disaster nature that lead to explosions and are characterized by a sharp increase in the front, a short duration and a wave character. Taking into account the placement of complex technological processes in buildings, it is now necessary to implement “flexible” space-planning solutions, for example, the use of girderless floors. The need to perform these studies is also due to the lack of methods and regulatory documents that regulate the calculation of the penetration of unbalanced monolithic slabs under dynamic loading. The purpose and objectives of this program are: to assess the influence of the thickness of the slab part of samples and the concrete class on the strength and crack resistance of elements, to obtain new experimental data describing the processes occurring in concrete and reinforcement, to identify patterns of destruction of samples. The test was carried out on a test stand based on a copra rig. The choice of sizes of prototypes is determined by the technical characteristics of this installation, the tasks of the experiment, the possibilities of manufacturing and testing models, and obtaining sufficiently reliable values of the parameters under study during testing. Twelve samples were tested for short-term dynamic loading and four samples for static loading. The following parameters vary: the concrete class (B15 and B20) and the thickness of the slab part of the sample (100 mm and 120 mm). The paper describes the dimensions, reinforcement, concrete classes of the studied samples, the sequence of work in the manufacture of samples, taking into account the installation of load cells. The result of this work is the development of a test method for prototypes.
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SOME NEW TECHNOLOGIES IN ROAD CONSTRUCTION

https://doi.org/10.34031/2618-7183-2020-3-1-62-69
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 62-69 p.
Abstract
This article discusses some new modern technologies in the construction of highways. The paper analyzes the use of such innovations as: various modifiers added to bitumen; advanced technologies of engineering surveys and computer-aided design of highways; geosynthetic materials for reinforcing the roadbed and asphalt concrete pavement; PBB; bituminous polymer road belts; geotextile; foam-glass rubble; rubber crumb. The advantages of using innovations in road construction are highlighted. Obstacles to the use of certain technologies are noted, taking into account the Russian reality.
The author concludes that the use of innovative materials becomes economically justified at the stage of construction and subsequent operation of the road surface. New technologies can not only improve the quality of roads, but also improve road safety.
Innovations lead to progressive changes and ensure the dynamic development of the construction industry, primarily by reducing the cost and timing of construction, improving the quality of constructed facilities, and improving the comfort of living and operation.
The paper discusses classical methods for the design works of the foundation and the GM made a review of modern structures and technologies on their device. In order to assess the possibility of using linear calculation for sheet piling fences, deep pit modeling was performed in the SCAD and PLAXIS software systems.
The results of the work are the following conclusions:
1. the method of increasing the efficiency of technologies at the device walling of the pit is proposed;
2. a finite element model of soil and GM collaboration was created.
To evaluate the effectiveness of the options, we used decision-making methods based on optimization criteria, taking into account the degree of risks involved in the work.
It is established that the necessary factor is the geotechnical support of technological impacts, which allows monitoring of works on the degree of safety and impact on highways.
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