Geotechnical skill is the ability to convert incomplete ground evidence into a defensible engineering model and recommendation.

Investigation planning

Start from project risks: loads, excavation, settlement tolerance, groundwater, neighboring structures and geological uncertainty.

Boreholes/testing

Use boreholes, trial pits, in-situ tests and sampling to investigate the ground. Method and spacing should follow project risk and applicable practice.

Soil classification

Classify soils using visual description and laboratory/field data, while recognizing variability between discrete investigation points.

Groundwater

Groundwater can affect effective stress, excavation, stability, uplift and construction method. Seasonal uncertainty should be considered.

Bearing/settlement

Foundation assessment must consider both strength and deformation. A foundation can satisfy bearing resistance yet still be unacceptable because of settlement.

Foundation selection

Compare shallow, raft, piled or improved-ground options using loads, soil profile, settlement, constructability, cost and adjacent assets.

Reports

A strong report distinguishes observed evidence, interpreted ground model, design parameters, recommendations and limitations.

Evidence

Build an academic case study from a fictional borehole log, derive a simple ground model and compare two foundation options with stated assumptions.

Sources