地圧測定用円柱形モールドゲージに関する基礎的研究
1975 年 91 巻 1043 号 p. 5-12
詳細
1975 年 91 巻 1043 号 p. 5-12
Theory and the laboratory test results on the low cost stress meter which has a structure that the strain rosettes are pre-cast into the cylindrical shaped moulding material, therefor, which is called a moulded gage, are described. Two types of the moulding materials, named type 1 and type 2, of which rigidities are small in comparison to those of the high modulus meters, have been developed for this purpose. The former is suitable to measure the absolute stress. On the other hand, the latter is suitableto monitor the stress change for long term measurement.
The meter has the following merits; First, the complete state of stress can be determined in a single measurement (Eq. 2 is the observation equation for this gage). Second, the gage sensitivity issufficiently high. Third, the results of the measurements are less dependent on the elastic constants of the rock in comparison to those obtained by the soft meter like the borehole deformation gage.
Satisfactory agreement between the actual and measured stresses was obtained by the laboratory test to simulate the measurement of the absolute stress.
