RU2784712C1 - Nuclear reactor protective shell - Google Patents

Abstract

FIELD: nuclear power plants.

SUBSTANCE: invention relates to a protective reinforced concrete fence of a nuclear power plant for protecting a nuclear reactor and the environment from external and internal force effects in case of possible emergency situations. The outer and inner layers of the containment shell of a nuclear reactor consist of arcuate plate elements with bulges directed inward and outward of the shell, supported at each other at the ends by means of vertical ribs with openings and prestressed puffs united along the contour of the elements of each layer.

EFFECT: increase in crack resistance and strength of the inner reinforced concrete layer of the nuclear reactor shell, which will significantly increase the safety of nuclear power plants in the event of an emergency explosive effect inside the shell.

1 cl, 2 dwg

Description

The invention relates to the field of construction, namely, to the protective reinforced concrete fences of nuclear power plants. The technical result of the claimed invention is to increase the safety of nuclear power plants, simplify the design of the protective reinforced concrete fence of nuclear power plants, reduce the physical volume and time of construction of nuclear power plants.

It is known that the passive safety system of power nuclear reactors is the protective shell of their reinforced concrete [1, 2].

The safest are two-layer (two-barrier) cylindrical reinforced concrete shells with two-layer domes of positive curvature.

The main purpose of the inner reinforced concrete shell is to contain radioactive steam-gas and aerosol products released as a result of a reactor accident.

The outer reinforced concrete shell is designed for external emergency action, which causes predominantly compressive forces in its elements, as a result of which it is manufactured without prestressing.

In the process of emergency loading, tensile forces arise in the inner shell. Since the formation of cracks in the reinforced concrete of the shell is not allowed, it is pre-stressed with metal ropes located in the channel formers inside the shell wall.

The disadvantage of the design is the complexity and laboriousness of performing work on the implementation of prestressing, high consumption of cable reinforcement and transverse reinforcement required to absorb tensile forces along the cable reinforcement during its tension during construction and during operation of the facility.

An invention is known, according to which, in order to ensure high crack resistance of the protective shell structure, it is made two-layer, and the surface of the inner layer consists of sections of cylindrical surfaces of constant curvature, resting along the entire height at the corners of a polyhedral prism forming the outer layer of the shell [3].

The disadvantages of this invention are the need for a high level of prestress in the outer layer of the shell, individually perceiving tensile forces that occur in the inner layer of the shell during an emergency force impact.

The tasks to be solved by the claimed invention are the development of a constructive technical proposal for a containment, which is feasible in a prefabricated and monolithic design, providing reliable protection of a nuclear reactor and the environment from external and internal force effects in case of possible emergency situations. The purpose of the invention is also to reduce the cost and construction time, increase the safety of nuclear power plants and reduce its operating costs.

The tasks are solved due to the fact that the outer and inner layers of the protective shell consist of arcuate plate elements with bulges directed inward and outward of the shell, which are supported on each other at the ends by means of vertical ribs with openings and are combined in each layer by prestressed puffs.

Figure 1 shows a horizontal section of the shell with a variant of puffs from the ropes;

Fig. 2 - the solution of the nodal parts of the shell with puffs from the rods.

1 - outer layer of the containment;

2 - inner layer of the containment;

3 - puffs from ropes;

4 - puffs from rods.

The claimed invention is implemented as follows:

As shown in FIG. 1, the outer (1) and inner (2) layers of the protective shell consist of arc-shaped plate elements in a monolithic or prefabricated design with bulges directed inward and outward of the shell. The arcuate elements of the outer and inner layers of the shell rest on each other at the ends with vertical longitudinal ribs (3) and are connected along the perimeter of the shell by prestressed puffs from ropes (4) or rods (5) passing through the longitudinal ribs.

When a load is applied from inside the shell, the arcuate sections of its inner layer, tending to straighten out, are loaded with tensile tightening forces (4, 5), while experiencing compression themselves. Even under extreme emergency loading, tensile stresses and cracks are not formed both in the concrete of the elements of the inner layer of the shell and in the places of their joints. Moreover, due to the efforts of expansion and joint work along the contour of the shell, the bearing capacity of these elements increases.

Shock loads from the outer side of the protective shell perceive the elements of its outer layer. In the concrete of these elements, due to the arcuate shape and puffs, there are also compressive forces and thrust forces that increase their bearing capacity.

The open location of the puffs in the proposed design of the containment allows you to freely monitor their condition and maintenance during operation. The location between the outer and inner layers of the shell protects them from the effects of atmospheric external and operational internal air. To simplify the operation of the tightening system, the vertical ribs of the shell can be made with openings that allow mounting work in the internal space between the layers of the shell along its circumference.

The use of the design of the containment shell of a nuclear reactor of a nuclear power plant, made in accordance with the invention, will make it possible to exclude cracking in the concrete of its outer and inner layers both during operation and in extreme emergency situations. This will significantly increase the reliability and safety of operation of the nuclear reactor of the power plant.

This design can be made in both monolithic and prefabricated versions. In the latter case, the construction time of the shell will be significantly reduced. The work of concrete of the inner and outer layers of the shell in compression will significantly reduce the consumption of reinforcement in the structure.

Free access to prestressed elements (ropes, rods) will greatly facilitate the control of their condition and prestressing.

Bibliography

1. L. A. Korobov, O. K. Nazar’ev, and V. Ya. Reinforced concrete spatial structures of nuclear and thermal power plants. M. Energoizdat. 1981 - 328 p.

2. Demidov A.P., Savchenko V.A. Protective shells of reactor compartments of foreign nuclear power plants // Energy construction abroad. 1989. No. 5 - p. 2-7.

3. Author's certificate SU 463376A "Protective shell of a nuclear reactor" N.G. Vasyagin, A.N. Zhivov, N.A. Pereyaslavtsev, I.V. Sukhenko, V.I. Shchotsky. Bull. No. 15, 1983.

Claims (1)

A protective two-layer cylindrical shell of a nuclear reactor, characterized in that the layers of the shell consist of arc-shaped plate elements of the inner layer with a bulge inside the shell and the outer layer with a bulge out of the shell, supported on each other at the ends by means of vertical ribs with openings and combined in each layer by prestressed puffs.

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