Radiation shielding method and device, and method of processing structure

摘要

A radiation shielding method and a device, and a method of processing a structure, in which a first radiation-shielded region (A1) is provided by disposing a first radiation-shielding device (100) outside a nuclear reactor vessel (41), a neutron flux detector (77) is moved into the radiation-shielded region (A1) through a conduit tube (65) by moving a thimble tube (68) from the nuclear reactor vessel (41), and an inspection/repair work of the nuclear reactor vessel (41) is then performed, so that an amount of radiation delivered to a worker can be easily and sufficiently reduced.

主权项

1. A radiation shielding method of shielding a body to be shielded arranged inside a nuclear reactor vessel, the method comprising:
providing a radiation-shielded region outside the nuclear reactor vessel; and moving the body to be shielded into the radiation-shielded region from the nuclear reactor vessel, wherein the providing includes providing a first radiation-shielded region on a wall surface of a cavity outside the nuclear reactor vessel and providing a second radiation-shielded region that surrounds a lower side of the nuclear reactor vessel, wherein the providing the first radiation-shielded region includes disposing a first vessel constituting a vertical wall of the first radiation-shielded region and a second vessel constituting a roof of the first radiation-shielded region, wherein the providing the second radiation-shielded region includes arranging a plurality of third vessels each having a shape in which a lower part is gradually increased in thickness to fill a gap between a cylindrical part of a concrete structure and the nuclear reactor vessel, closely side by side outside the nuclear reactor vessel along a circumferential direction, and arranging a plurality of fourth vessels each having a rod-shape to fill a gap between the nuclear reactor vessel and a support table supported by the concrete structure, closely side by side at the lower side of the nuclear reactor vessel to form a circle, and the providing includes filling the first vessel with a plurality of shielding material filled jackets which are pouch-shape vessels whose shapes are changeable, and the plurality of shielding material filled jackets are filled with a plurality of granular shielding materials, wherein the disposing the first vessel includes disposing two vertical plates at a certain distance in a direction perpendicular to a longitudinal direction of a plurality of conduit tubes, and forming a plurality of penetrating grooves opening upward along an up and down direction and aligned in a right and left direction through which the plurality of conduit tubes pass through in the respective vertical plates, and the filling the first vessel with a plurality of shielding material filled jackets includes providing the plurality of shielding material filled jackets between the two vertical plates.