These steps will be followed for the experiment

Zero-time adjustment

1. Use the reference bar to perform the zero-time adjustment. Apply coupling agent to the ends of the reference bar, and press the transducers firmly against the ends of the bar until a stable transit time is displayed. Adjust the zero reference until the displayed transit time agrees with the value marked on the bar.
   
   

Surface Preparation

2. At the point of observation, the concrete surface shall be suitably prepared, and any plaster or other coating shall be removed to expose the concrete surface. For this purpose, the use of carborundum stones or grinders may be adopted. However, care shall be taken to avoid any damage to concrete surface or concrete structure.
   
3. Apply a coupling agent to the transducer faces or the test surface, or both.
   
   

Ultrasonic Measurements

4. Press the faces of the transducers firmly against the surfaces of the concrete until a stable transit time is displayed, and measure the transit time.
   
5. Determine the straight-line distance between centers of transducer faces.
   

Observations and Calculation:

Pulse velocity reported to the nearest 0.01km/s

Concrete quality grading = _____________
Results:

Location of test or identification of specimen:
Location of transducers:
Pulse velocity:
Concrete Quality Grading:


Precautions:

The quality of the coupling is critically important to the accuracy and maximum range of the method. Inadequate coupling will result in unstable and inaccurate time measurements, and will significantly shorten the effective range of the instrument. Repeat measurements should be made at the same location to minimize erroneous readings due to poor coupling.