Earthquake protection requirements for high-rise structures mean that reinforcing steels for certain countries must be subjected to specific tests.
Standard-compliant cyclic tensilecompression tests (carried out on ribbed steel rods cut to length) depart significantly from the elastic range of the specimen. Grip-to-grip separation, stroke and frequency are specified by the standard according to the specimen diameter. After the test the deformed specimen is
examined visually for cracks. The power and short-term energy needed for these tests is considerable. Zwick has developed a servohydraulic
testing machine with hydraulic accumulator for this test, enabling loads of over 1200 kN to be applied with strokes of more than 20 mm at over 1 Hz.

• Earthquake tests to standard
• Hydraulic, parallel-closing specimen grips for compression and tensile loading