PURPOSE: To enable simultaneous measurement of changes in size and weight of a cement-based porous material, by combining a non-contact type displacement gauge and a loadcell type weight measuring device.
CONSTITUTION: An object to be measured is a plate sample 1 of cement-based porous material and is topped with a metallic cap 2. An eddy current displacement sensor 3 is arranged slightly separated from the cap 2 and an electric signal from the sensor 3 is taken out via a cable 4. The eddy current generated between the sensor 3 and the cap 2 varies in the intensity with the size of the clearance. The changes in the size of the sample 1 can be measured by capturing the variation as displacement. A loadcell 5 is arranged below a holder 5a of the sample 1 to measure changes in the weight of the sample 1. An electric signal from the loadcell 5 is taken out via a cable 6. It should be noted that a displacement of the loadcell 5 itself if small for weight change, much smaller than variation in the size of the sample 1. Thus, the displacement of the loadcell 5 itself can be ignored, in no way affecting the measurement of changes in the size.
TSUKAMOTO AKIRA
MIURA KENJI
