| Earthquake shaking tables are major equipment of seismic experiments. Traditional earthquake shaking tables mainly use analog control technology, however, with the rapid development of digital technology, it has been widely applied in earthquake shaking tables and improves the system stability, reliability and accuracy. Digital technology using on shaking table has overcome the disadvantage of analog control, such as large structure, control complexity and high costs. In this thesis, a new type of digital electro-hydraulic servo valve is designed and used in earthquake shaking table. The rotary motion and linear motion of the spool performs full functions of general electro-hydraulic servo valve's control level and power level, and the valve is characterized by simple structure, fast response, strong anti-pollution, etc.An earthquake shaking table using the new digital electro-hydraulic servo valve as the fluid control components of system is designed according to the technical issues, and mathematical modeling of the three parts of system are established and analyzed in simulation investigation. Finally, the experiments are carried out, which indicates that the newly designed earthquake shaking table simulates well the artificial waves and the seismic waves. The main tasks of this paper are as follows:Chapter 1 makes a summary of some relevant information about the history and trend of this research, and then introduces the purpose, meaning and creative point of this thesis.Chapter 2 introduces the design of the digital electro-hydraulic servo valve, and introduces structure and principle of the valve and the control system of the earthquake shaking table.Chapter 3 establishes the mathematical model of all parts of system, analyzed the system in open-loop and closed-loop simulation investigation.Chapter 4 establishes the testing system of the earthquake shaking table, and the experimental study is performed.Chapter 5 is the summarization of this thesis and prospect.
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