Ultrasonic pulse velocity test

 Ultrasonic pulse velocity method is an non-destructive test which is used to determine the compressive strength of concrete structure without any damage.

  • This method consists of measuring the time of travel of and ultrasonic pulse passing through the concrete to be tested.
  • In this method, A pulse generator circuit is used which consists of electronic circuit and transducer.
  • Electronic circuit generates pulses and transducer transforms it into mechanical energy having vibration frequencies in the range of 15 to 50 kHz.
  • The time of travel between initial onset and the reception of the pulse is measured electronically.
  • The path length between transducer divided by the time of travel gives the average velocity of wave propagation.

  • When mechanical impulses are applied to a solid mass, three different kinds of waves are generated - longitudinal wave, shear wave and surface wave.
  • The longitudinal waves travel about twice as fast as the other two types. The shear waves are not so fast, the surface waves are the slowest. 
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