Field observations
Surface, weather, termination, groundwater and pre-drill depth.
Below the readings table, Field observations records the conditions the test was performed in.
The fields
| Field | Notes |
|---|---|
| Surface condition | The state of the surface tested |
| Weather | Conditions at the time |
| Termination type | Why the test stopped |
| Groundwater depth (mm) | Water encountered, if any |
| Pre-drill depth (mm) | Depth pre-drilled before testing began |
| Termination / refusal reason | What caused refusal |
| General notes | Anything else |
Why these matter
A DCP result is only meaningful alongside the conditions it was taken in. The same pavement tested after a week of rain and after a dry month gives different numbers, and moisture is not something the readings themselves reveal.
Pre-drill depth is the one most often forgotten. If you pre-drilled through a bound surface layer, the depths in the readings table are offset from the true surface, and anyone reading the profile later needs to know by how much.
Termination type and refusal reason together explain a short test. A test that terminated at 300 mm on rock is a valid result; one that stopped because the operator ran out of time is not, and the profile alone cannot distinguish them.