To provide a pressure measurement method inside a manhole, a pressure measurement device, and a manhole lid having it for surely and accurately measuring an abnormal pressure generated inside a manhole.
This pressure measurement device arranged on the back face of the manhole lid or a side wall inside the manhole functions so that the tip of an indenter is brought into collision with or pushed into the surface of a specimen when the indenter receives an abnormally high pressure generated inside the manhole and indentation by the indenter is formed on the surface of the specimen. After the pressure inside the manhole is increased abnormally, the specimen is removed for measuring the size of the indentation, and on the basis of the measurement value, a burden load value forming the indentation having the same measurement value and/or the same area value is specified from sampling data previously obtained by a hardness test of the specimen.
HATA KAZUTAKA
SHIMIZU ETSUJI
NISHIYAMA HIROSHI
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