The geotechnical subsurface investigation is basically the collection of soil samples at various depths under ground grade level. The depth is recorded and the soil samples are taken to the Laboratory for analysis. The panel of analysis includes the following Unconfined Compression Test:
- Wet Weight of Sample
- Diameter
- Initial and Final Height
- Dry Weight
- Wet Density
- Dry Density
- Moisture
- Unconfined Strength
The most important tests are the Grain Size distribution / Sieve analysis to aid in the classification of the soil, an example looks like the following:
- 53.01 % passing #30
- 41.11 % passing #50
- 33.15 % passing #100
- 28.58 % passing #200
and the Atterberg Limits Test to evaluate the soil expansive potential, an example looks like
the following:
- Liquid Limit 55.00
- Plastic Limit 26.80
- Plasticity Index 28.20
With the convergence of the laboratory test results, we can conclude that the soil geological properties encountered in all the exploration logs for a project are fundamentally similar in nature. We can, furthermore, confirm that our laboratory testing for the subsurface exploration, of the materials found, is successful as similar soil properties are found in the published USGS and other geological maps.