Study on development of a small three components borehole strain meter

为了收集数据，制作直径为6 cm、长度为20 cm的小钻孔三分量应变仪，进行了各种实验。首先制作了一个由黄铜制成的小型钻孔容器，并采用半导体应变片作为传感器。通过防水、灵敏度等实验，将应变仪设置在野树山地壳运动观测站隧道的钻孔中。结果表明，应变仪具有足够的灵敏度，可用于记录潮汐。此外，还对仪器的漂移和噪声进行了研究。其次，制作了三分量应变仪，并将其安装在Aburatsubo地壳运动观测站的水库中。通过对应变门、菱镁感应、涡流感应等多种传感器的漂移、灵敏度、温度效应等进行测试，并结合基本数据制作出实用的小型三分量钻孔应变仪。

In order to collect data to make a small borehole three components strainmeter with a diameter of 6 cm and a length of 20 cm, various experiments were performed. Firstly a small borehole vessel made from brass was produced and a semiconductor strain gage was employed as a sensor. After various experiments like water proof and sensitivity the strain meter was set into a borehole in the tunnel of Nokogiriyama crustal movement observatory. It was found that the strain meter had a enough sensitivity to record earth tide. Drift and noise of the meter were also investigated. Secondly, a three components strainmeter was produced and it was installed in a water in the vault of Aburatsubo crustal movement observatory. A drift, sensitivity, temperature effect and so on were tested for various sensors like strain gate, magnesensor and eddy current sensor and basic data to produce practical small three components borehole strain meter.