岩石のクリープ試験におけるサーボ試験機の制御特性

1.はじめに

2.サーボ試験機のモデル

3.岩石の線形モデルによる検討

4.岩石の非線形モデルによる検討

 4.1 基礎式

 4.2 三次クリープにおける制御限界

 4.3 三次クリープ領域における変位速度と残存寿命の関係

 4.4 実験結果との比較

5.考察およびまとめ

参考文献


Controllability of Servo-Controlled Testing Machine in creep Test of Rock under Uniaxial Compression

Abstract

In this study, the control performance of servo-controlled testing machine applied to creep test was investigated.

Firstly, supposing a linear rock model, the characteristic polynomial of machine-rock system was obtained and examined. It was found that the system is stable in primary and secondary creep regions, but unstable in tertiary creep region.

Secondly, the computer simulation was conducted for tertiary creep region, using a non-linear visco-elastic rock model which was recently proposed by authors. The results of simulation are summarized as;

1) The control performance is mainly influenced by natural frequency of testing machine, gain of servo-system and rigidity of hydraulic ram.

2) Complete creep curve of Class U rock can be obtained more easily than that of Class T rock.

Finally, creep testing under uniaxial compression was conducted using Inada granite, Sanjome andesite and Kawazu tuff as rock samples. It is found that the results of simulation agrees with the result of experiment.