PURPOSE: To attain not only to stabilize the measurement of potential but also to facilitate the mounting and replacement of a collimation electrode, by using a collimation electrode apparatus for an alkaline environemt comprising the metal lead electrode arranged in a solid phase filler low in contact potential difference.
CONSTITUTION: A coolimation electrode apparatus 3 for an alkaline environment is constituted so that a metal lead electrode 7 is arranged in the solid phase filler 8 comprising calcium hydroxide or gypsum within a case 9 and one end of the case 9 is sealed in a cover 10 and the solid phase filter 8 is exposed to the other end of said case 9 to attain the convenience of the direct contact with concrete 1. A plurality of collimation electrode apparatuses 3 and a common reinforcing bar terminal 4 are connected to a potential recording apparatus 11 by electric wires 6 and the effective output voltage E of each collimation electrode apparatus 3 is applied to the voltometer 5 of the potential recording apparatus 11 through a switch.
ISHIKAWA MITSUO
YAMAMOTO SATORU
NIPPON BOSHOKU KOGYO KK