Earthquake simulator
The seismic simulator consists of a rigid platform with an area of 4.0 x 4.0 m2 and a weight of 100 kN. With the appropriate oil pressure pumps, valves and automations it has the ability to simultaneously and with high precision controlled oscillation in all six degrees of freedom (6 DOF ). This oscillation is carried out by controlling two horizontal hydraulic pistons in the X direction, two horizontal hydraulic pistons in the Y direction and four hydraulic and one pneumatic piston in the vertical Z direction. The maximum translational acceleration which the seismic simulator can develop in in the two horizontal directions is 2 g, while at the same time in the Z direction it is 4 g. At the same time, during the operation of the seismic simulator there is a restriction that the movement in any transport direction cannot be greater than ±100 mm and the speed cannot exceed 1000 mm / sec.
The seismic simulator is controlled by an analog system, which in turn is controlled by a digital system using a computer. This check is done continuously according to X, Y and Z of the respective accelerations, speeds and movements of the platform by comparing them to the desired movements and, if necessary, their correction follows. The motion of the test surface of the seismic simulator can be a sinusoidal excitation, a random motion or even an earthquake, as recorded in nature, but also an artificial earthquake with desired characteristics at frequencies from DC up to 50 Hz.
Data collection system
Specific Unit with 64 channels Analogue/Digital with high sweeping frequency, for the attendance of dynamic phenomena from several receivers (Strain gauges, accelerometers, etc).
Data analysis
Evaluation of input signals or specimen response records with the software libraries of the computer of the Laboratory for Earthquake Engineering. The raw data can be immediately evaluated and printed out or can be stored in any modern means of electronic storage, through special devices (CD writers, disk writers, tape writers). The control unit has been connected through optical fibres to the visitor’s rooms for further data evaluation and reduction.