[SSS17-01] Development of displacement enlargement system and an application for small strain strain seismograph
Keywords:development of displacement enlargement system, application of the system, small strain seismograph, extensometer
The Institute owns the observation station of the horizontal tunnel and obtains data with a 30m long quartz strain meter. In order to observe the strain between the fixed end of the 30m strain meter and the first support table (distance 1.1 m) of the first quartz glass, the displacement magnification device (about 60 times the magnification) was installed and the variation was recorded. As a result, the recording by the expansion system was almost the same record as the strain meter of 30m length. In fact it is estimated that the same results as the 30m strain meter can be obtained even in the variation of shorter intervals. Details will be reported in the presentation.
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