Shielding structure

The present invention provides a structure for shielding high energy neutrons generated from a radiation generation device disposed in a structure. Namely, a shielding filler comprising a hardening material such as soil cement is disposed being in contact with a body of the structure. A water permeable material comprising a mesh-like or fabric material is disposed being in contact with the shielding filler. An introduction means in communication with water in a water storage vessel introduces water to the water permeable material. A water blocking sheet comprising an air cap sheet or a vinyl chloride sheet is disposed between the body of the structure and the shielding filler to prevent the water contained in the shielding filler from permeating into the body of the structure. Then, water can be supplied to the shielding filler by using capillary phenomenon. As a result, the shielding filler is prevented from being dried, and the weight in a unit volume can be kept constant. Since water of the water permeable material is in communication with the water storage vessel by way of the introduction means, the amount of water can be maintained automatically by the capillary phenomenon due to osmotic pressure. (I.S.)