ABSTRACT
Triaxial rock testing system is an important tool for studying rock mechanics, and it is widely used in the research field of oil and gas exploration, geotechnical engineering, construction engineering, and geological hazard, etc (Liu, X., Q. Zhang & Z. Yue 2013). At present, the domestic triaxial rock testing systems are divided into two types: conventional triaxial testing machine and true triaxial testing machine, and according to dierent research purposes, there were developed some new testing machines with added special functions, such as creep, static and dynamic state, dierent temperature, infiltration, and other recombination (Tang, H. & S. Li 2004, Sun. X., M. He & C. Liu 2005, Zhang. K., Z. Yin & Z. Xu 2003, Chen. A., J. Gu, J. Shen, Z. Ming & X. Zhang 2004). Internationally, the most famous electro-hydraulic servo rock testing machines are produced by GCTS (Geotechnical Consulting and Testing Systems) Corporation, MTS (Mechanical Testing and Sensing Solutions) Systems Corporation, Instron Corporation and Shimadzu Corporation (Huang. R., D. Xu, X. Fu, X. Yu, Y. Huang & Y. Liu 2008, Wang. B., J. Zhu & A. Wu 2010, Zhu. J., Y. Jiang & L. Wang 2010, Zhao. Y., Z. Wan, Y. Zhang, F. Qu, G. Xie, X. Wei & W. Ma 2008 ). In addition, France TOP INDUSTRIE Corporation, Germany Schenk Corporation and Switzerland W+B Corporation also produce rock testing machines (Martin, C.D. &
R. Christiansson 2009, Xu. J., S. Peng & G. Yin 2010, Wu. A. 2010). Now, most existing triaxial rock testing systems are equipped with all-digital servo feedback technology and advanced technology in dierent countries, such as EDC digital measure and control instrument of Germany DOLI Corporation, servo valve of the U.S. MOOG Corporation, servo motor of Japanese Panasonic Corporation, mute oil pump of Japanese NACHI Corporation and other key components and parts (Lv. J., Y. Cui, J. Liu & H. Lu 2010, Zhang. Y. 2004, Chen. J. 2008). So, there are remarkable improvements in its system functionality, performance, stability, etc.
