| 摘要 |
PROBLEM TO BE SOLVED: To provide a protection case for a radio sensor favorably protecting the radio sensor buried in a concrete structure from heat, alkali, moisture in concrete, stress applied to the concrete, and the like and not being foreign matter in the concrete structure. SOLUTION: This protection case has 2-4 layers and favorably comprises a protection layer 2 including an outermost layer 3 made of a nonconductive inorganic material and an inner layer 4 made of a vibration absorbing material for protecting the radio sensor 7 buried in the concrete structure by the protection layer 2. When an opening 1 is formed, the opening is closed by a lid part 6 with porous structure and an object to be detected having passing through the lid part is detected by the built-in radio sensor 7. The protection case has a shape preventing stress concentration such as columnar shape, semi-capsule shape, oval shape, spherical shape, and the like. COPYRIGHT: (C)2005,JPO&NCIPI |
